83 results on '"Churchyard, Gavin J."'
Search Results
2. Cost-effectiveness of Preventive Therapy for Tuberculosis With Isoniazid and Rifapentine Versus Isoniazid Alone in High-Burden Settings.
- Author
-
Johnson, Karl T, Churchyard, Gavin J, Sohn, Hojoon, and Dowdy, David W
- Subjects
- *
ANTIBIOTICS , *TUBERCULOSIS prevention , *HIV infection complications , *ANTIRETROVIRAL agents , *COMBINATION drug therapy , *COST effectiveness , *HIV infections , *ISONIAZID , *LIFE expectancy , *MEDICAL care costs , *PEOPLE with disabilities , *PROBABILITY theory , *TUBERCULOSIS , *DISEASE prevalence , *THERAPEUTICS - Abstract
Background A short-course regimen of 3 months of weekly rifapentine and isoniazid (3HP) has recently been recommended by the World Health Organization as an alternative to at least 6 months of daily isoniazid (isoniazid preventive therapy [IPT]) for prevention of tuberculosis (TB). The contexts in which 3HP may be cost-effective compared to IPT among people living with human immunodeficiency virus are unknown. Methods We used a Markov state transition model to estimate the incremental cost-effectiveness of 3HP relative to IPT in high-burden settings, using a cohort of 1000 patients in a Ugandan HIV clinic as an emblematic scenario. Cost-effectiveness was expressed as 2017 US dollars per disability-adjusted life year (DALY) averted from a healthcare perspective over a 20-year time horizon. We explored the conditions under which 3HP would be considered cost-effective relative to IPT. Results Per 1000 individuals on antiretroviral therapy in the reference scenario, treatment with 3HP rather than IPT was estimated to avert 9 cases of TB and 1 death, costing $9402 per DALY averted relative to IPT. Cost-effectiveness depended strongly on the price of rifapentine, completion of 3HP, and prevalence of latent TB. At a willingness to pay of $1000 per DALY averted, 3HP is likely to be cost-effective relative to IPT only if the price of rifapentine can be greatly reduced (to approximately $20 per course) and high treatment completion (85%) can be achieved. Conclusions 3HP may be a cost-effective alternative to IPT in high-burden settings, but cost-effectiveness depends on the price of rifapentine, achievable completion rates, and local willingness to pay. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
3. Molecular characterisation of clinical and environmental isolates of Mycobacterium kansasii isolates from South African gold mines.
- Author
-
Kwenda, Geoffrey, Churchyard, Gavin J., Thorrold, Catherine, Heron, Ian, Stevenson, Karen, Duse, Adriano G., and Marais, Elsé
- Subjects
- *
MYCOBACTERIUM , *LUNG diseases , *GOLD miners , *MOLECULAR epidemiology , *MYCOBACTERIA , *POLYMERASE chain reaction , *DISEASES - Abstract
Mycobacterium kansasii (M. kansasii) is a major cause of non-tuberculous mycobacterial pulmonary disease in the South African gold-mining workforce, but the source of infection and molecular epidemiology are unknown. This study investigated the presence of M. kansasii in gold and coal mine and associated hostel water supplies and compared the genetic diversity of clinical and environmental isolates of M. kansasii. Five M. kansasii and ten other potentially pathogenic mycobacteria were cultured mainly from showerhead biofilms. Polymerase chain reaction-restriction analysis of the hsp65 gene on 196 clinical and environmental M. kansasii isolates revealed 160 subtype I, eight subtype II and six subtype IV strains. Twenty-two isolates did not show the typical M. kansasii restriction patterns, suggesting that these isolates may represent new subtypes of M. kansasii. In contrast to the clonal population structure found amongst the subtype I isolates from studies in other countries, DNA fingerprinting of 114 clinical and three environmental subtype I isolates demonstrated genetic diversity amongst the isolates. This study demonstrated that showerheads are possible sources of M. kansasii and other pathogenic non-tuberculous mycobacterial infection in a gold-mining region, that subtype I is the major clinical isolate of M. kansasii strain and that this subtype exhibits genetic diversity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
4. A Trial of Mass Isoniazid Preventive Therapy for Tuberculosis Control.
- Author
-
Churchyard, Gavin J., Fielding, Katherine J., Lewis, James J., Coetzee, Leonie, Corbett, Elizabeth L., Godfrey-Faussett, Peter, Hayes, Richard J., Chaisson, Richard E., and Grant, Alison D.
- Subjects
- *
ISONIAZID , *DRUG efficacy , *HEALTH of miners , *ANTITUBERCULAR agents , *PREVENTION , *THERAPEUTICS ,TUBERCULOSIS transmission - Abstract
The article discusses research which investigated efficacy of mass isoniazid preventive therapy in interrupting tuberculosis transmission among South African gold mine workers. It reports designation of either intervention or control clusters to miners involved in the study, administration of isoniazid and analysis of the direct effects of isoniazid. It also offers brief details relating to the primary and secondary outcomes recorded and characteristics of study participants.
- Published
- 2014
- Full Text
- View/download PDF
5. A Phase IIA Randomized Clinical Trial of a Multiclade HIV- 1 DNA Prime Followed by a Multiclade rAd5 HIV-1 Vaccine Boost in Healthy Adults (HVTN204).
- Author
-
Churchyard, Gavin J., Morgan, Cecilia, Adams, Elizabeth, Hural, John, Graham, Barney S., Moodie, Zoe, Grove, Doug, Gray, Glenda, Bekker, Linda-Gail, McElrath, M. Juliana, Tomaras, Georgia D., Goepfert, Paul, Kalams, Spyros, Baden, Lindsey R., Lally, Michelle, Dolin, Raphael, Blattner, William, Kalichman, Artur, Figueroa, J. Peter, and Pape, Jean
- Subjects
- *
VACCINES , *CLINICAL trials , *MEDICAL statistics , *ADENOVIRUS diseases , *SEROTYPES - Abstract
Background: The safety and immunogenicity of a vaccine regimen consisting of a 6-plasmid HIV-1 DNA prime (envA, envB, envC, gagB, polB, nefB) boosted by a recombinant adenovirus serotype-5 (rAd5) HIV-1 with matching inserts was evaluated in HIV-seronegative participants from South Africa, United States, Latin America and the Caribbean Methods: 480 participants were evenly randomized to receive either: DNA (4 mg IM by Biojector) at 0, 1 and 2 months, followed by rAd5 (1010 PU IM by needle/syringe) at 6 months; or placebo. Participants were monitored for reactogenicity and adverse events throughout the 12-month study. Peak and duration of HIV-specific humoral and cellular immune responses were evaluated after the prime and boost Results: The vaccine was well tolerated and safe. T-cell responses, detected by interferon-&ggr;(IFN-&ggr;) ELISpot to global potential T-cell epitopes (PTEs) were observed in 70.8% (136/192) of vaccine recipients overall, most frequently to Gag (54.7%) and to Env (54.2%). In U.S. vaccine recipients T-cell responses were less frequent in Ad5 sero-positive versus seronegative vaccine recipients (62.5% versus 85.7% respectively, p = 0.035). The frequency of HIV-specific CD4+ and CD8+ T-cell responses detected by intracellular cytokine staining were similar (41.8% and 47.2% respectively) and most secreted $2 cytokines. The vaccine induced a high frequency (83.7%-94.6%) of binding antibody responses to consensus Group M, and Clades A, B and C gp140 Env oligomers. Antibody responses to Gag were elicited in 46% of vaccine recipients Conclusion: The vaccine regimen was well-tolerated and induced polyfunctional CD4+ and CD8+ T-cells and multi-clade anti-Env binding antibodies [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
6. HIV infection and tuberculosis in South Africa: an urgent need to escalate the public health response.
- Author
-
Abdool Karim, Salim S., Churchyard, Gavin J., Abdool Karim, Quarraisha, and Lawn, Stephen D.
- Subjects
- *
HIV , *TUBERCULOSIS , *EPIDEMICS , *PREVENTIVE medicine , *EPIDEMIOLOGY - Abstract
The article provides information on HIV and tuberculosis epidemics in South Africa and how the government has responded to them. The first cases of AIDS in South Africa occurred in 1982 and the HIV epidemic has evolved through the concentrated epidemic phase, initiation of the generalised epidemic, rapid spread of HIV, and AIDS mortality phase. Tuberculosis was introduced in the 17th century into South Africa by the arrival of European immigrants from Great Britain and the Netherlands. Achievements and innovations in the responses to HIV and tuberculosis are discussed. Steps for HIV and tuberculosis control are outlined.
- Published
- 2009
- Full Text
- View/download PDF
7. Tuberculosis Preventive Therapy in the Era of HIV Infection: Overview and Research Priorities.
- Author
-
Churchyard, Gavin J., Scano, Fabio, Grant, Alison D., and Chaisson, Richard E.
- Subjects
- *
TUBERCULOSIS prevention , *THERAPEUTICS , *DRUG efficacy , *ANTIRETROVIRAL agents , *MEDICAL care , *HIV infections , *HIV-positive persons , *HIV , *RESEARCH - Abstract
The recognition of tuberculosis (TB) as a major cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected persons has led to renewed interest in TB preventive therapy and its incorporation into the essential package of health care for these individuals. Despite convincing data regarding its efficacy, TB preventive therapy has not been widely implemented. Further work is needed to determine how to overcome the barriers to the implementation of such therapy, including how best to exclude the presence of active TB before providing preventive therapy. Such issues as the optimal duration of preventive therapy for and the role of TB preventive therapy in the treatment of individuals receiving antiretroviral therapy remain to be defined. Ongoing research will help to determine how best to use this intervention in the care of HIV-infected persons and in the control of TB on a wider basis. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
8. Morbidity and Mortality in South African Gold Miners: Impact of Untreated Disease Due to Human Immunodeficiency Virus.
- Author
-
Corbett, Elizabeth L., Churchyard, Gavin J., Charalambos, Salome, Samh, Badara, Moloi, Vicky, claytopn, Tim C., Grant, Alison D., Murray, Jill, Hayes, Richard J., and De Cock, Kevin M.
- Subjects
- *
MINERS , *HIV-positive persons , *MORTALITY , *DISEASES - Abstract
Deals with a study which determined the mortality and morbidity among South African miners infected with HIV. Methods; Results; Discussion.
- Published
- 2002
- Full Text
- View/download PDF
9. A Short Regimen for Rifampin-Resistant Tuberculosis.
- Author
-
Churchyard, Gavin J
- Abstract
An editorial is presented on the treatments for multidrug-resistant and rifampin-resistant tuberculosis, which is a global health threat. It discusses the World Health Organization (WHO) guidelines of using multiple second-line agents having injectable drugs, advancement in Bangladesh regimen saw better success rates with seven drug cocktail having high-dose isoniazid, clofazimine.
- Published
- 2019
- Full Text
- View/download PDF
10. Recurrent Tuberculosis: Relapse, Reinfection, and HIV.
- Author
-
Chaisson, Richard E. and Churchyard, Gavin J.
- Subjects
- *
TUBERCULOSIS , *HIV infection complications , *HIV-positive persons , *DISEASES - Abstract
In this article, the authors comment on articles "Impact of HIV Infection on the Recurrence of Tuberculosis in South India," by Sujatha Narayanan and colleagues and "High Rates of Recurrence in HIV-Infected and HIV-Uninfected Patients with Tuberculosis," by Judith R. Glynn and team. They believe that the reason for the relapse in these individuals is the inclusion of ofloxacin in nonstandard and abbreviated regiments. They add that the recurrence of the disease is more common that projected.
- Published
- 2010
- Full Text
- View/download PDF
11. Tuberculosis and HIV Coinfection: Current State of Knowledge and Research Priorities.
- Author
-
Gerald Friedland, Churchyard, Gavin J., and Nardell, Edward
- Subjects
- *
TUBERCULOSIS , *HIV infections - Abstract
The article discusses various reports published within the issue, including one by Paul Nunn and colleagues on the global status of tuberculosis (TB) and human immunodeficiency virus (HIV) infection and another by Philip Onyebuyoh and colleagues on treatment strategies for TB and HIV coinfection.
- Published
- 2007
- Full Text
- View/download PDF
12. An ecological study to evaluate the association of Bacillus Calmette-Guerin (BCG) vaccination on cases of SARS-CoV2 infection and mortality from COVID-19.
- Author
-
Chimoyi, Lucy, Velen, Kavindhran, Churchyard, Gavin J., Wallis, Robert, Lewis, James J., and Charalambous, Salome
- Subjects
- *
SARS-CoV-2 , *COVID-19 , *MORTALITY , *BCG vaccines , *LOG-linear models - Abstract
As the SARS-CoV2 pandemic has progressed, there have been marked geographical differences in the pace and extent of its spread. We evaluated the association of BCG vaccination on morbidity and mortality of SARS-CoV2, adjusted for country-specific responses to the epidemic, demographics and health. SARS-CoV2 cases and deaths as reported by 31 May 2020 in the World Health Organization situation reports were used. Countries with at least 28 days following the first 100 cases, and available information on BCG were included. We used log-linear regression models to explore associations of cases and deaths with the BCG vaccination policy in each country, adjusted for population size, gross domestic product, proportion aged over 65 years, stringency level measures, testing levels, smoking proportion, and the time difference from date of reporting the 100th case to 31 May 2020. We further looked at the association that might have been found if the analyses were done at earlier time points. The study included 97 countries with 73 having a policy of current BCG vaccination, 13 having previously had BCG vaccination, and 11 having never had BCG vaccination. In a log-linear regression model there was no effect of country-level BCG status on SARS-CoV2 cases or deaths. Univariable log-linear regression models showed a trend towards a weakening of the association over time. We found no statistical evidence for an association between BCG vaccination policy and either SARS-CoV2 morbidity or mortality. We urge countries to rather consider alternative tools with evidence supporting their effectiveness for controlling SARS-CoV2 morbidity and mortality. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
13. A trial of mass isoniazid preventive therapy for tuberculosis control.
- Author
-
Churchyard, Gavin J, Fielding, Katherine L, and Grant, Alison D
- Published
- 2014
- Full Text
- View/download PDF
14. Opportunities afforded by new drugs for tuberculosis
- Author
-
Churchyard, Gavin J, Friedland, Gerald, Fielding, Katherine, and Nardell, Edward
- Published
- 2010
- Full Text
- View/download PDF
15. Empiric tuberculosis treatment in South African primary health care facilities - for whom, where, when and why: Implications for the development of tuberculosis diagnostic tests.
- Author
-
McCarthy, Kerrigan, Fielding, Katherine, Churchyard, Gavin J., and Grant, Alison D.
- Subjects
- *
TUBERCULOSIS patients , *TUBERCULOSIS treatment , *TUBERCULOSIS diagnosis , *PRIMARY health care , *MEDICAL care - Abstract
Background: The extent and circumstances under which empiric tuberculosis (TB) treatment (treatment without microbiological confirmation at treatment initiation) is administered in primary health care settings in South Africa are not well described. Methods: We used data from a pragmatic evaluation of Xpert MTB/RIF in which persons undergoing TB investigations by PHC nurses were followed for six months. Following Xpert or smear-microscopy at enrolment, investigations for tuberculosis were undertaken at the discretion of health care workers. We identified persons whose TB treatment was initiated empirically (no microbiological confirmation at time of treatment initiation at a primary health care facility) and describe pathways to treatment initiation. Results: Of 4665 evaluable participants, 541 persons were initiated on treatment of whom 167 (31%) had negative sputum tests at enrolment. Amongst these 167, the median number of participant visits to health care providers prior to treatment initiation was 3 (interquartile range [IQR] 2–4). Chest radiography, sputum culture or hospital referral was done in 106/167 (63%). Reasons for TB treatment start were: 1) empiric (n = 82, 49%); 2) a positive laboratory test (n = 49, 29%); 3) referral and treatment start at a higher level of care (n = 28, 17%); and 4) indeterminable (n = 8, 5%). Empiric treatment accounted for 15% (82/541) of all TB treatment initiations and 1.7% (82/4665) of all persons undergoing TB investigations. Chest radiography findings compatible with TB (63/82 [77%]) were the basis for treatment initiation amongst the majority of empirically treated participants. Microbiological confirmation of TB was subsequently obtained for 11/82 (13%) empirically-treated participants. Median time to empiric treatment start was 3.9 weeks (IQR 1.4–11 weeks) after enrolment. Conclusion: Uncommon prescription of empiric TB treatment with reliance on chest radiography in a nurse-managed programme underscores the need for highly sensitive TB diagnostics suitable for point-of-care, and strong health systems to support TB diagnosis in this setting. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
16. Pragmatic cluster-randomized trial of home-based preventive treatment for TB in Ethiopia and South Africa (CHIP-TB).
- Author
-
Malhotra, Akash, Nonyane, Bareng Aletta Sanny, Shirey, Evan, Mulder, Christiaan, Hippner, Piotr, Mulatu, Fiseha, Ratshinanga, Andani, Mitiku, Petros, Cohn, Silvia, Conradie, Gideon, Chihota, Violet, Chaisson, Richard E., Churchyard, Gavin J., Golub, Jonathan, Dowdy, David, Sohn, Hojoon, Charalambous, Salome, Bedru, Ahmed, and Salazar-Austin, Nicole
- Subjects
- *
TUBERCULOSIS , *CLUSTER randomized controlled trials , *CLINICS , *CHILD death , *CONTACT tracing , *CONTINUUM of care - Abstract
Background: Each year, 1 million children develop TB resulting in over 200,000 child deaths. TB preventive treatment (TPT) is highly effective in preventing TB but remains poorly implemented for household child contacts. Home-based child contact management and TPT services may improve access to care. In this study, we aim to evaluate the effectiveness and cost-effectiveness of home-based contact management with TPT initiation in two TB high-burden African countries, Ethiopia and South Africa. Methods: This pragmatic cluster randomized trial compares home-based versus facility-based care delivery models for contact management. Thirty-six clinics with decentralized TB services (18 in Ethiopia and 18 in South Africa) were randomized in a 1:1 ratio to conduct either home-based or facility-based contact management. The study will attempt to enroll all eligible close child contacts of infectious drug-sensitive TB index patients diagnosed and treated for TB by one of the study clinics. Child TB contact management, including contact tracing, child evaluation, and TPT initiation and follow-up, will take place in the child's home for the intervention arm and at the clinic for the control arm. The primary outcome is the cluster-level ratio of the number of household child contacts less than 15 years of age in Ethiopia and less than 5 years of age in South Africa initiated on TPT per index patient, comparing the intervention to the control arm. Secondary outcomes include child contact identification and the TB prevention continuum of care. Other implementation outcomes include acceptability, feasibility, fidelity, cost, and cost-effectiveness of the intervention. Discussion: This implementation research trial will determine whether home-based contact management identifies and initiates more household child contacts on TPT than facility-based contact management. Trial registration: NCT04369326. Registered on April 30, 2020. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
17. Tuberculosis Infectiousness and Host Susceptibility.
- Author
-
Turner, Richard D., Chiu, Christopher, Churchyard, Gavin J., Esmail, Hanif, Lewinsohn, David M., Gandhi, Neel R., and Fennelly, Kevin P.
- Subjects
- *
RESPIRATORY disease risk factors , *COUGH , *MYCOBACTERIUM tuberculosis , *INFECTION prevention , *INFECTIOUS disease transmission , *DISEASE susceptibility , *TUBERCULOSIS ,TUBERCULOSIS transmission - Abstract
The transmission of tuberculosis is complex. Necessary factors include a source case with respiratory disease that has developed sufficiently for Mycobacterium tuberculosis to be present in the airways. Viable bacilli must then be released as an aerosol via the respiratory tract of the source case. This is presumed to occur predominantly by coughing but may also happen by other means. Airborne bacilli must be capable of surviving in the external environment before inhalation into a new potential host-steps influenced by ambient conditions and crowding and by M. tuberculosis itself. Innate and adaptive host defenses will then influence whether new infection results; a process that is difficult to study owing to a paucity of animal models and an inability to measure infection directly. This review offers an overview of these steps and highlights the many gaps in knowledge that remain. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
18. Resistance to Mycobacterium tuberculosis infection among highly TB exposed South African gold miners.
- Author
-
Chihota, Violet N., Ntshiqa, Thobani, Maenetje, Pholo, Mansukhani, Raoul, Velen, Kavindhran, Hawn, Thomas R., Wallis, Robert, Grant, Alison D., Churchyard, Gavin J., and Fielding, Katherine
- Subjects
- *
GOLD miners , *MYCOBACTERIUM tuberculosis , *MYCOBACTERIAL diseases , *TUBERCULOSIS , *ODDS ratio , *LOGISTIC regression analysis , *CONFIDENCE intervals - Abstract
Background: Despite high exposure to Mycobacterium tuberculosis, a small proportion of South African goldminers resist TB infection. We determined, among long-service gold miners i) the proportion who were TB uninfected and ii) epidemiological factors associated with being uninfected. Methods: We enrolled HIV-negative gold miners aged 33–60 years with ≥15 years' service and no history of TB or silicosis. Miners were defined as TB uninfected if i) QuantiFERON-TB Gold Plus (QFT-Plus) negative or ii) in a stricter definition, QFT-Plus-negative and zero-response on TST and as resisters if they were of Black/African ethnicity and negative on both tests. Logistic regression was used to identify epidemiological factors associated with being TB uninfected. Results: Of 307 participants with a QFT-Plus result, median age was 48 years (interquartile range [IQR] 44–53), median time working underground was 24 years (IQR 18–28), 303 (99%) were male and 91 (30%) were QFT-Plus-negative. The odds of being TB uninfected was 52% lower for unskilled workers (adjusted odds ratio [aOR] 0.48; 95% confidence interval [CI] 0.27–0.85; p = 0.013). Among 281 participants of Black/African ethnicity, 71 (25%) were QFT-Plus negative. Miners with a BMI ≥30 were less likely to be TB uninfected (OR 0.38; 95% CI 0.18–0.80). Using the stricter definition, 44.3% (136/307) of all miners were classified as either TB uninfected (35; 26%) or infected, (101; 74%) and the associations remained similar. Among Black/African miners; 123 were classified as either TB uninfected (23; 19%) or infected (100; 81%) using the stricter definition. No epidemiological factors for being TB uninfected were identified. Conclusions: Despite high cumulative exposure, a small proportion of miners appear to be resistant to TB infection and are without distinguishing epidemiological characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
19. Tuberculosis in sub-Saharan Africa: opportunities, challenges, and change in the era of antiretroviral treatment.
- Author
-
Corbett, Elizabeth L, Marston, Barbara, Churchyard, Gavin J, and De Cock, Kevin M
- Subjects
- *
CHEST diseases , *TUBERCULOSIS research , *ANTIRETROVIRAL agents , *EPIDEMIOLOGY , *PUBLIC health research - Abstract
Rapid scale-up of antiretroviral treatment programmes is happening in Africa, driven by international advocacy and policy directives and supported by unprecedented donor funding and technical assistance. This welcome development offers hope to millions of HIV-infected Africans, among whom tuberculosis is the major cause of serious illness and death. Little in the way of HIV diagnosis or care was previously offered to patients with tuberculosis, by either national tuberculosis or AIDS control programmes, with tuberculosis services focused exclusively on diagnosis and treatment of rising numbers of patients. Tuberculosis control in Africa has yet to adapt to the new climate of antiretroviral availability. Many barriers exist, from drug interactions to historic differences in the way that tuberculosis and HIV are perceived, but failure to successfully integrate HIV and tuberculosis control will threaten the viability of both programmes. Here, we review tuberculosis epidemiology in Africa and policy implications of HIV/AIDS treatment scale-up. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
20. Performance of GeneXpert MTB/RIF for Diagnosing Tuberculosis Among Symptomatic Household Contacts of Index Patients in South Africa.
- Author
-
Velen, Kavindhran, Podewils, Laura J, Shah, N Sarita, Lewis, James J, Dinake, Tiro, Churchyard, Gavin J, Reichler, Mary, and Charalambous, Salome
- Subjects
- *
MULTIDRUG-resistant tuberculosis , *COUGH , *MYCOBACTERIUM tuberculosis , *HIV , *TUBERCULOSIS , *HOUSEHOLDS - Abstract
Background We describe the performance of GeneXpert MTB/RIF (Xpert) for diagnosing tuberculosis (TB) among symptomatic household contacts (HHCs) of rifampicin-resistant and drug-sensitive index cases. Methods We conducted a cross-sectional study among HHCs of recently diagnosed (<2 weeks) smear-positive and Xpert-positive index cases in the Bojanala District, South Africa. The HHCs were screened for TB symptoms; persons with ≥1 TB symptom provided 1 sputum for smear microscopy, Xpert, and mycobacterial growth indicator tube (MGIT) culture. Diagnostic test performance of Xpert was determined using MGIT as the reference standard. Results From August 2013 to July 2015, 619 HHCs from 216 index cases were enrolled: 60.6% were female, median age was 22 years (interquartile range, 9–40), and 126 (20.4%) self-reported/tested human immunodeficiency virus positive. A total of 54.3% (336 of 619) of contacts had ≥1 TB symptom (cough, fever, night sweats, weight loss), 297 of 336 (88.4%) of which provided a sputum; 289 (97.3%) had complete testing and 271 were included in the analysis. In total, 42 (6.8%) of 619 HHCs had microbiologically confirmed TB. The MGIT identified 33 HHCs as positive for Mycobacterium tuberculosis ; of these, 7 were positive on Xpert resulting in a sensitivity of 21.2% (95% confidence interval [CI], 9.0–38.9), specificity of 98.3% (95% CI, 95.6–99.5), positive predictive value of 63.6% (95% CI, 30.8–89.1), and negative predictive value of 90.0 (95% CI, 85.7–93.4). Conclusions Among symptomatic HHCs investigated for TB, Xpert performed suboptimally compared with MGIT culture. The poor performance of Xpert for diagnosing TB suggests that a more sensitive test, such a Xpert Ultra or culture, may be needed to improve yield of contact investigation, where feasible. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
21. Using mHealth to improve tuberculosis case identification and treatment initiation in South Africa: Results from a pilot study.
- Author
-
Maraba, Noriah, Hoffmann, Christopher J., Chihota, Violet N., Chang, Larry W., Ismail, Nazir, Candy, Sue, Madibogo, Edwin, Katzwinkel, Marc, Churchyard, Gavin J., and McCarthy, Kerrigan
- Subjects
- *
MOBILE health , *TUBERCULOSIS treatment , *MEDICAL personnel , *PILOT projects - Abstract
Background: Tuberculosis (TB) incidence in South Africa is among the highest globally. Initial loss to follow-up (ILFU), defined as not starting on TB treatment within 28 days of testing positive, is undermining control efforts. We assessed the feasibility, acceptability, and potential of a mHealth application to reduce ILFU. Methods: An mHealth application was developed to capture patients TB investigation data, provide results and monitor treatment initiation. This was implemented in two primary health clinics (PHC) in inner-city Johannesburg. Feasibility was assessed by comparing documentation of personal details, specimen results for same individuals during implementation period (paper register and Mhealth application). Effectiveness was assessed by comparing proportion of patients with results within 48 hours, and proportion started on treatment within 28 days of testing TB positive during pre- implementation (paper register) and implementation (mHealth application) periods. In-depth interviews with patients and providers were conducted to assess acceptability of application. Results: Pre-implementation, 457 patients were recorded in paper registers [195 (42.7%) male, median age 34 years (interquartile range IQR (28–40), 45 (10.5%) sputum Xpert positive]. During implementation, 319 patients were recorded in paper register and the mHealth application [131 (41.1%) male, median age 32 years (IQR 27–38), 33 (10.3%) sputum Xpert positive]. The proportion with complete personal details: [mHealth 95.0% versus paper register 94.0%, (p = 0.54)] and proportion with documented results: [mHealth 97.4% versus paper register 97.8%, (p = 0.79)] were not different in the two methods. The proportion of results available within 48 hours: [mHealth 96.8% versus paper register 68.6%), (p <0.001)], and the proportion on treatment within 28 days [mHealth 28/33 (84.8%) versus paper register 30/44 (68.2%), (p = 0.08)] increased during implementation but was not statistically significant. In-depth interviews showed that providers easily integrated the mHealth application into routine TB investigation and patients positively received the delivery of results via text message. Time from sputum collection to TB treatment initiation decreased from 4 days (pre-implementation) to 3 days but was not statistically significant. Conclusions: We demonstrated that implementation of the mHealth application was feasible, acceptable to health care providers and patients, and has potential to reduce the time to TB treatment initiation and ILFU in PHC settings. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
22. Household point of care CD4 testing and isoniazid preventive therapy initiation in a household TB contact tracing programme in two districts of South Africa.
- Author
-
Page-Shipp, Liesl, Lewis, James J., Velen, Kavindhran, Senoge, Sedikanelo, Zishiri, Elizabeth, Popane, Flora, Chihota, Violet N., Clark, Dave, Churchyard, Gavin J., and Charalambous, Salome
- Subjects
- *
HIV , *TUBERCULOSIS microbiology , *ISONIAZID , *HIV infections , *TUBERCULOSIS patients , *THERAPEUTICS - Abstract
Background: In South Africa, TB household contact tracing provides an opportunity for increased TB and HIV case finding. We aimed to determine the effect of two new potential interventions for TB contact tracing programmes: Point of Care CD4 (PoC CD4) on HIV linkage to care and household Isoniazid Preventive Therapy (IPT) provision on uptake and retention of IPT. Methods: A pragmatic, three-arm, cluster-randomized trial was undertaken. TB Household contacts were randomised to 3 arms: 1) Standard of Care TB and HIV testing (SOC); 2) SOC with POC CD4 for those testing HIV positive; 3) SOC with POC CD4 and IPT for eligible household members. Linkage to care within 90 days was assessed either through patient visits (at 10 weeks and 6 months) or via telephonic contact. Results: 2,243 index TB patients and 3,012 contacts (64,3% female, median age 30 years) were enrolled. On self-report, 26(1.2%) were currently receiving TB treatment and 1816 (60.3%) reported a prior HIV test. HIV testing uptake was 34.7% in the SoC arm, 40.2% in the PoC CD4 arm (RR1.16, CI 0.99–1.36, p-value = 0.060) and 39.9% in the PoC CD4 + HH-IPT arm (RR = 1.15, CI 0.99–1.35, p-value = 0.075). Linkage to care within 3 months was 30.8% in the SoC arm and 42.1% in the POC CD4 arms (RR 1.37; CI: 0.68–2.76, p-value = 0.382). 20/21 contacts (95.2%) initiated IPT in the PoC CD4 + HH-IPT arm, compared to 3/20 (15.0%) in the PoC CD4 arm (p = 0.004; p-value from Fisher’s exact test < 0.001). Among 3,008 contacts screened for tuberculosis, 15 (3.4%) had bacteriologically confirmed TB with an overall yield of TB of 0.5% (95% CI: 0.3%, 0.8%). Conclusions: Household PoC CD4 testing and IPT initiation is feasible. There was only weak evidence that PoCCD4 led to a small increase in HCT uptake and no evidence for an increase in linkage-to-care. IPT initiation and completion was increased by the household intervention. Although feasible, these interventions had low impact due to the low uptake of HIV testing in households. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
23. Impact of Targeted Tuberculosis Vaccination Among a Mining Population in South Africa: A Model-Based Study.
- Author
-
Shrestha, Sourya, Chihota, Violet, White, Richard G., Grant, Alison D., Churchyard, Gavin J., and Dowdy, David W.
- Subjects
- *
TUBERCULOSIS prevention , *HIV , *IMMUNIZATION , *MINERAL industries , *ANTIRETROVIRAL agents , *STATISTICAL models , *MIXED infections ,TUBERCULOSIS transmission - Abstract
Optimizing the use of new tools, such as vaccines, may play a crucial role in reaching global targets for tuberculosis (TB) control. Some of the most promising candidate vaccines target adults, although high-coverage mass vaccinations may be logistically more challenging among this population than among children. Vaccine-delivery strategies that target high-risk groups or settings might yield proportionally greater impact than do those that target the general population. We developed an individual-based TB transmission model representing a hypothetical population consisting of people who worked in South African gold mines or lived in associated labor-sending communities. We simulated the implementation of a postinfection adult vaccine with 60% efficacy and a mean effect duration of 10 years. We then compared the impact of a mine-targeted vaccination strategy, in which miners were vaccinated while in the mines, with that of a community-targeted strategy, in which random individuals within the labor-sending communities were vaccinated. Mine-targeted vaccination averted an estimated 0.37 TB cases per vaccine dose compared with 0.25 for community-targeted vaccination, for a relative efficacy of 1.46 (95% range, 1.13-1.91). The added benefit of mine targeted vaccination primarily reflected the disproportionate demographic burden of TB among the population of adult males as a whole. As novel vaccines for TB are developed, venue-based vaccine delivery that targets high-risk demographic groups may improve both vaccine feasibility and the impact on transmission. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
24. Research Roadmap for Tuberculosis Transmission Science: Where Do We Go From Here and How Will We Know When We're There?
- Author
-
Auld, Sara C., Kasmar, Anne G., Dowdy, David W., Mathema, Barun, Gandhi, Neel R., Churchyard, Gavin J., Rustomjee, Roxana, and Shah, N. Sarita
- Subjects
- *
TUBERCULOSIS prevention , *HIV infections , *EPIDEMICS , *DISEASE management , *COMMUNICABLE diseases , *PREVENTION of infectious disease transmission , *TUBERCULOSIS epidemiology , *PREVENTION of communicable diseases , *MEDICAL research ,TUBERCULOSIS transmission - Abstract
High rates of tuberculosis transmission are driving the ongoing global tuberculosis epidemic, and there is a pressing need for research focused on understanding and, ultimately, halting transmission. The ongoing tuberculosis-human immunodeficiency virus (HIV) coepidemic and rising rates of drug-resistant tuberculosis in parts of the world add further urgency to this work. Success in this research will require a concerted, multidisciplinary effort on the part of tuberculosis scientists, clinicians, programs, and funders and must span the research spectrum from biomedical sciences to the social sciences, public health, epidemiology, cost-effectiveness analyses, and operations research. Heterogeneity of tuberculosis disease, both among individual patients and among communities, poses a substantial challenge to efforts to interrupt transmission. As such, it is likely that effective interventions to stop transmission will require a combination of approaches that will vary across different epidemiologic settings. This research roadmap summarizes key gaps in our current understanding of transmission, as laid out in the preceding articles in this series. We also hope that it will be a call to action for the global tuberculosis community to make a sustained commitment to tuberculosis transmission science. Halting transmission today is an essential step on the path to end tuberculosis tomorrow. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
25. Strategies to Accelerate HIV Care and Antiretroviral Therapy Initiation After HIV Diagnosis: A Randomized Trial.
- Author
-
Hoffmann, Christopher J., Mabuto, Tonderai, Ginindza, Sibuse, Fielding, Katherine L., Kubeka, Griffths, Dowdy, David W., Churchyard, Gavin J., and Charalambous, Salome
- Abstract
Objective: Determine the effectiveness of strategies to increase linkage to care after testing HIV positive at mobile HIV testing in South Africa. Design: Unmasked randomized controlled trial. Methods: Recruitment of adults testing HIV positive and not currently in HIV care occurred at 7 mobile HIV counseling and testing units in urban, periurban, and rural South Africa with those consenting randomized 1:1:1:1 into 1 of 4 arms. Three strategies were compared with standard of care (SOC): point-of-care CD4 count testing (POC CD4), POC CD4 plus longitudinal strengths-based counseling (care facilitation; CF), and POC CD4 plus transport reimbursement (transport). Participants were followed up telephonically and through clinic records and analyzed with an intention-to-treat analysis. Results: From March 2013 to October 2014, 2558 participants were enrolled, of whom 160 were excluded postrandomization. Compared with the SOC arm where 298 (50%) reported having entered care, linkage to care was 319 (52%) for POC CD4, hazard ratio (HR) 1.0 [95% confidence interval (CI): 0.89 to 1.2, P = 0.6]; 331 (55%) for CF, HR: 1.1 (95% CI: 0.84 to 1.3, P = 0.2); and 291 (49%) for transport, HR 0.97 (95% CI: 0.83 to 1.1, P = 0.7). Linkage to care verified with clinical records that occurred for 172 (29%) in the SOC arm; 187 (31%) in the POC CD4 arm, HR: 1.0 (95% CI: 0.86 to 1.3, P = 0.6); 225 (38%) in the CF arm, HR: 1.4 (95% CI: 1.1 to 1.7, P = 0.001); and 180 (31%) in the transport arm, HR: 1.1 (95% CI: 0.88 to 1.3, P = 0.5). Conclusions: CF improved verified linkage to care from 29% to 38%. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
26. A clinical scoring system to prioritise investigation for tuberculosis among adults attending HIV clinics in South Africa.
- Author
-
Hanifa, Yasmeen, Fielding, Katherine L., Chihota, Violet N., Adonis, Lungiswa, Charalambous, Salome, Foster, Nicola, Karstaedt, Alan, McCarthy, Kerrigan, Nicol, Mark P., Ndlovu, Nontobeko T., Sinanovic, Edina, Sahid, Faieza, Stevens, Wendy, Vassall, Anna, Churchyard, Gavin J., and Grant, Alison D.
- Subjects
- *
TUBERCULOSIS , *BODY mass index , *ANTHROPOMETRY , *MICROBIOLOGICAL assay - Abstract
Background: The World Health Organization (WHO) recommendation for regular tuberculosis (TB) screening of HIV-positive individuals with Xpert MTB/RIF as the first diagnostic test has major resource implications. Objective: To develop a diagnostic prediction model for TB, for symptomatic adults attending for routine HIV care, to prioritise TB investigation. Design: Cohort study exploring a TB testing algorithm. Setting: HIV clinics, South Africa. Participants: Representative sample of adult HIV clinic attendees; data from participants reporting ≥1 symptom on the WHO screening tool were split 50:50 to derive, then internally validate, a prediction model. Outcome: TB, defined as “confirmed” if Xpert MTB/RIF, line probe assay or M. tuberculosis culture were positive; and “clinical” if TB treatment started without microbiological confirmation, within six months of enrolment. Results: Overall, 79/2602 (3.0%) participants on ART fulfilled TB case definitions, compared to 65/906 (7.2%) pre-ART. Among 1133/3508 (32.3%) participants screening positive on the WHO tool, 1048 met inclusion criteria for this analysis: 52/515 (10.1%) in the derivation and 58/533 (10.9%) in the validation dataset had TB. Our final model comprised ART status (on ART > 3 months vs. pre-ART or ART < 3 months); body mass index (continuous); CD4 (continuous); number of WHO symptoms (1 vs. >1 symptom). We converted this to a clinical score, using clinically-relevant CD4 and BMI categories. A cut-off score of ≥3 identified those with TB with sensitivity and specificity of 91.8% and 34.3% respectively. If investigation was prioritised for individuals with score of ≥3, 68% (717/1048) symptomatic individuals would be tested, among whom the prevalence of TB would be 14.1% (101/717); 32% (331/1048) of tests would be avoided, but 3% (9/331) with TB would be missed amongst those not tested. Conclusion: Our clinical score may help prioritise TB investigation among symptomatic individuals. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
27. Measuring mortality due to HIV-associated tuberculosis among adults in South Africa: Comparing verbal autopsy, minimally-invasive autopsy, and research data.
- Author
-
Karat, Aaron S., Tlali, Mpho, Fielding, Katherine L., Charalambous, Salome, Chihota, Violet N., Churchyard, Gavin J., Hanifa, Yasmeen, Johnson, Suzanne, McCarthy, Kerrigan, Martinson, Neil A., Omar, Tanvier, Kahn, Kathleen, Chandramohan, Daniel, and Grant, Alison D.
- Subjects
- *
HIV infection complications , *AUTOPSY , *MORTALITY - Abstract
Background: The World Health Organization (WHO) aims to reduce tuberculosis (TB) deaths by 95% by 2035; tracking progress requires accurate measurement of TB mortality. International Classification of Diseases (ICD) codes do not differentiate between HIV-associated TB and HIV more generally. Verbal autopsy (VA) is used to estimate cause of death (CoD) patterns but has mostly been validated against a suboptimal gold standard for HIV and TB. This study, conducted among HIV-positive adults, aimed to estimate the accuracy of VA in ascertaining TB and HIV CoD when compared to a reference standard derived from a variety of clinical sources including, in some, minimally-invasive autopsy (MIA). Methods and findings: Decedents were enrolled into a trial of empirical TB treatment or a cohort exploring diagnostic algorithms for TB in South Africa. The WHO 2012 instrument was used; VA CoD were assigned using physician-certified VA (PCVA), InterVA-4, and SmartVA-Analyze. Reference CoD were assigned using MIA, research, and health facility data, as available. 259 VAs were completed: 147 (57%) decedents were female; median age was 39 (interquartile range [IQR] 33–47) years and CD4 count 51 (IQR 22–102) cells/μL. Compared to reference CoD that included MIA (n = 34), VA underestimated mortality due to HIV/AIDS (94% reference, 74% PCVA, 47% InterVA-4, and 41% SmartVA-Analyze; chance-corrected concordance [CCC] 0.71, 0.42, and 0.31, respectively) and HIV-associated TB (41% reference, 32% PCVA; CCC 0.23). For individual decedents, all VA methods agreed poorly with reference CoD that did not include MIA (n = 259; overall CCC 0.14, 0.06, and 0.15 for PCVA, InterVA-4, and SmartVA-Analyze); agreement was better at population level (cause-specific mortality fraction accuracy 0.78, 0.61, and 0.57, for the three methods, respectively). Conclusions: Current VA methods underestimate mortality due to HIV-associated TB. ICD and VA methods need modifications that allow for more specific evaluation of HIV-related deaths and direct estimation of mortality due to HIV-associated TB. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
28. Priority-Setting for Novel Drug Regimens to Treat Tuberculosis: An Epidemiologic Model.
- Author
-
Kendall, Emily A., Shrestha, Sourya, Cohen, Ted, Nuermberger, Eric, Dooley, Kelly E., Gonzalez-Angulo, Lice, Churchyard, Gavin J., Nahid, Payam, Rich, Michael L., Bansbach, Cathy, Forissier, Thomas, Lienhardt, Christian, and Dowdy, David W.
- Subjects
- *
TUBERCULOSIS treatment , *TUBERCULOSIS mortality , *RIFAMPIN , *DISEASE incidence , *MORTALITY , *INFECTIOUS disease transmission - Abstract
Background: Novel drug regimens are needed for tuberculosis (TB) treatment. New regimens aim to improve on characteristics such as duration, efficacy, and safety profile, but no single regimen is likely to be ideal in all respects. By linking these regimen characteristics to a novel regimen's ability to reduce TB incidence and mortality, we sought to prioritize regimen characteristics from a population-level perspective.Methods and Findings: We developed a dynamic transmission model of multi-strain TB epidemics in hypothetical populations reflective of the epidemiological situations in India (primary analysis), South Africa, the Philippines, and Brazil. We modeled the introduction of various novel rifampicin-susceptible (RS) or rifampicin-resistant (RR) TB regimens that differed on six characteristics, identified in consultation with a team of global experts: (1) efficacy, (2) duration, (3) ease of adherence, (4) medical contraindications, (5) barrier to resistance, and (6) baseline prevalence of resistance to the novel regimen. We compared scale-up of these regimens to a baseline reflective of continued standard of care. For our primary analysis situated in India, our model generated baseline TB incidence and mortality of 157 (95% uncertainty range [UR]: 113-187) and 16 (95% UR: 9-23) per 100,000 per year at the time of novel regimen introduction and RR TB incidence and mortality of 6 (95% UR: 4-10) and 0.6 (95% UR: 0.3-1.1) per 100,000 per year. An optimal RS TB regimen was projected to reduce 10-y TB incidence and mortality in the India-like scenario by 12% (95% UR: 6%-20%) and 11% (95% UR: 6%-20%), respectively, compared to current-care projections. An optimal RR TB regimen reduced RR TB incidence by an estimated 32% (95% UR: 18%-46%) and RR TB mortality by 30% (95% UR: 18%-44%). Efficacy was the greatest determinant of impact; compared to a novel regimen meeting all minimal targets only, increasing RS TB treatment efficacy from 94% to 99% reduced TB mortality by 6% (95% UR: 1%-13%, half the impact of a fully optimized regimen), and increasing the efficacy against RR TB from 76% to 94% lowered RR TB mortality by 13% (95% UR: 6%-23%). Reducing treatment duration or improving ease of adherence had smaller but still substantial impact: shortening RS TB treatment duration from 6 to 2 mo lowered TB mortality by 3% (95% UR: 1%-6%), and shortening RR TB treatment from 20 to 6 mo reduced RR TB mortality by 8% (95% UR: 4%-13%), while reducing nonadherence to the corresponding regimens by 50% reduced TB and RR TB mortality by 2% (95% UR: 1%-4%) and 6% (95% UR: 3%-10%), respectively. Limitations include sparse data on key model parameters and necessary simplifications to model structure and outcomes.Conclusions: In designing clinical trials of novel TB regimens, investigators should consider that even small changes in treatment efficacy may have considerable impact on TB-related incidence and mortality. Other regimen improvements may still have important benefits for resource allocation and outcomes such as patient quality of life. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
29. Autopsy Prevalence of Tuberculosis and Other Potentially Treatable Infections among Adults with Advanced HIV Enrolled in Out-Patient Care in South Africa.
- Author
-
Karat, Aaron S., Omar, Tanvier, von Gottberg, Anne, Tlali, Mpho, Chihota, Violet N., Churchyard, Gavin J., Fielding, Katherine L., Johnson, Suzanne, Martinson, Neil A., McCarthy, Kerrigan, Wolter, Nicole, Wong, Emily B., Charalambous, Salome, and Grant, Alison D.
- Subjects
- *
TUBERCULOSIS treatment , *HIV infections , *DISEASE prevalence , *BRONCHOALVEOLAR lavage , *CLINICAL trials - Abstract
Background: Early mortality among HIV-positive adults starting antiretroviral therapy (ART) remains high in resource-limited settings, with tuberculosis (TB) the leading cause of death. However, current methods to estimate TB-related deaths are inadequate and most autopsy studies do not adequately represent those attending primary health clinics (PHCs). This study aimed to determine the autopsy prevalence of TB and other infections in adults enrolled at South African PHCs in the context of a pragmatic trial of empiric TB treatment (“TB Fast Track”). Methods and Findings: Adults with CD4 ≤150 cells/μL, not on ART or TB treatment, were enrolled to TB Fast Track and followed up for at least six months. Minimally invasive autopsy (MIA) was conducted as soon as possible after death. Lungs, liver, and spleen were biopsied; blood, CSF, and urine aspirated; and bronchoalveolar lavage fluid obtained. Samples underwent mycobacterial, bacterial, and fungal culture; molecular testing (including Xpert® MTB/RIF); and histological examination. 34 MIAs were conducted: 18 (53%) decedents were female; median age was 39 (interquartile range 33–44) years; 25 (74%) deaths occurred in hospitals; median time from death to MIA was five (IQR 3–6) days. 16/34 (47%) had evidence of TB (14/16 [88%] with extrapulmonary disease; 6/16 [38%] not started on treatment antemortem); 23 (68%) had clinically important bacterial infections; four (12%) cryptococcal disease; three (9%) non-tuberculous mycobacterial disease; and two (6%) Pneumocystis pneumonia. Twenty decedents (59%) had evidence of two or more concurrent infections; 9/16 (56%) individuals with TB had evidence of bacterial disease and two (13%) cryptococcal disease. Conclusions: TB, followed by bacterial infections, were the leading findings at autopsy among adults with advanced HIV enrolled from primary care clinics. To reduce mortality, strategies are needed to identify and direct those at highest risk into a structured pathway that includes expedited investigation and/or treatment of TB and other infections. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
30. Diagnostic Accuracy of Lateral Flow Urine LAM Assay for TB Screening of Adults with Advanced Immunosuppression Attending Routine HIV Care in South Africa.
- Author
-
Hanifa, Yasmeen, Fielding, Katherine L., Chihota, Violet N., Adonis, Lungiswa, Charalambous, Salome, Karstaedt, Alan, McCarthy, Kerrigan, Nicol, Mark P., Ndlovu, Nontobeko T., Sahid, Faieza, Churchyard, Gavin J., and Grant, Alison D.
- Subjects
- *
TUBERCULOSIS diagnosis , *HIV infection complications , *URINALYSIS , *BIOLOGICAL assay , *IMMUNOSUPPRESSION ,DISEASES in adults - Abstract
Background: We assessed the diagnostic accuracy of Determine TB-LAM (LF-LAM) to screen for tuberculosis among ambulatory adults established in HIV care in South Africa. Methods: A systematic sample of adults attending for HIV care, regardless of symptomatology, were enrolled in the XPHACTOR study, which tested a novel algorithm for prioritising investigation with Xpert MTB/RIF. In this substudy, restricted to participants with enrolment CD4<200x106/l, urine was stored at enrolment for later testing with LF-LAM. Sputum was sent for immediate Xpert MTB/RIF if any of: current cough, fever ≥3 weeks, body mass index (BMI)<18.5kg/m2, CD4<100x106/l (or <200x106/l if pre-ART), weight loss ≥10% or strong clinical suspicion were present; otherwise, sputum was stored for Xpert testing at study completion. Participants were reviewed monthly, with reinvestigation if indicated, to 3 months, when sputum and blood were taken for mycobacterial culture. We defined tuberculosis as “confirmed” if Xpert, line probe assay or culture for M. tuberculosis within six months of enrolment were positive, and “clinical” if tuberculosis treatment started without microbiological confirmation. Results: Amongst 424 participants, 61% were female and 57% were taking ART (median duration 22 months); median age, CD4 and BMI were 39 years, 111x106/l, and 23 kg/m2. 56/424 (13%) participants had tuberculosis (40 confirmed, 16 clinical). 24/424 (5.7%) vs. 8/424 (1.9%) were LAM-positive using grade 1 vs. grade 2 cut-off. Using grade 1 cut-off, sensitivity for confirmed TB (all clinical TB excluded) was 12.5% (95% CI 4.2%, 26.8%) and in CD4<100x106/l vs. CD4 ≥100x106/l was 16.7% (95% CI 4.7%, 37.4%) vs. 6.3% (95% CI 0.2%, 30.2%). Specificity was >95% irrespective of diagnostic reference standard, CD4 stratum, or whether grade 1 or grade 2 cut-off was used. Conclusion: Sensitivity of LF-LAM is too low to recommend as part of intensified case finding in ambulatory patients established in HIV care. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
31. Household HIV Testing Uptake among Contacts of TB Patients in South Africa.
- Author
-
Velen, Kavindhran, Lewis, James J., Charalambous, Salome, Page-Shipp, Liesl, Popane, Flora, Churchyard, Gavin J., and Hoffmann, Christopher J.
- Subjects
- *
DIAGNOSIS of HIV infections , *TUBERCULOSIS , *CONTACT tracing , *HEALTH counseling - Abstract
Background: In high HIV prevalence settings, offering HIV testing may be a reasonable part of contact tracing of index tuberculosis (TB) patients. We evaluated the uptake of HIV counselling and testing (HCT) among household contacts of index TB patients and the proportion of newly diagnosed HIV-infected persons linked into care as part of a household TB contact tracing study. Methods: We recruited index TB patients at public health clinics in two South African provinces to obtain consent for household contact tracing. During scheduled household visits we offered TB symptom screening to all household members and HCT to individuals ≥14years of age. Factors associated with HCT uptake were investigated using a random effects logistic regression model. Results & Discussion: Out of 1,887 listed household members ≥14 years old, 984 (52%) were available during a household visit and offered HCT of which 108 (11%) self-reported being HIV infected and did not undergo HCT. Of the remaining 876, a total of 304 agreed to HCT (35%); 26 (8.6%) were newly diagnosed as HIV positive. In multivariable analysis, factors associated with uptake of HCT were prior testing (odds ratio 1.6; 95% confidence interval [CI]: 1.1–2.3) and another member in the household testing (odds ratio 2.4; 95% CI: 1.7–3.4). Within 3 months of testing HIV-positive, 35% reported initiating HIV care. Conclusion: HCT as a component of household TB contact tracing reached individuals without prior HIV testing, however uptake of HIV testing was poor. Strategies to improve HIV testing in household contacts should be evaluated. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
32. The timing of tuberculosis after isoniazid preventive therapy among gold miners in South Africa: a prospective cohort study.
- Author
-
Hermans, Sabine M., Grant, Alison D., Chihota, Violet, Lewis, James J., Vynnycky, Emilia, Churchyard, Gavin J., and Fielding, Katherine L.
- Subjects
- *
TUBERCULOSIS treatment , *ISONIAZID , *GOLD mining , *PREVENTIVE medicine , *MATHEMATICAL models , *MEDICAL care , *TUBERCULOSIS microbiology , *ANTITUBERCULAR agents , *TUBERCULOSIS epidemiology , *DRUG resistance in microorganisms , *GOLD , *LONGITUDINAL method , *MYCOBACTERIUM tuberculosis , *PROGNOSIS , *RESEARCH funding , *DISEASE incidence , *DISEASE prevalence , *THERAPEUTICS - Abstract
Background: The durability of isoniazid preventive therapy (IPT) in preventing tuberculosis (TB) is limited in high-prevalence settings. The underlying mechanism (reactivation of persistent latent TB or reinfection) is not known. We aimed to investigate the timing of TB incidence during and after IPT and associated risk factors in a very high TB and HIV-prevalence setting, and to compare the observed rate with a modelled estimate of TB incidence rate after IPT due to reinfection.Methods: In a post-hoc analysis of a cluster-randomized trial of community-wide IPT among South African gold miners, all intervention arm participants that were dispensed IPT for at least one of the intended 9 months were included. An incident TB case was defined as any participant with a positive sputum smear or culture, or with a clinical TB diagnosis assigned by a senior study clinician. Crude TB incidence rates were calculated during and after IPT, overall and by follow-up time. HIV status was not available. Multivariable Cox regression was used to analyse risk factors by follow-up time after IPT. Estimates from a published mathematical model of trial data were used to calculate the average reinfection TB incidence in the first year after IPT.Results: Among 18,520 participants (96% male, mean age 41 years, median follow-up 2.1 years), 708 developed TB. The TB incidence rate during the intended IPT period was 1.3/100 person-years (pyrs; 95% confidence interval (CI), 1.0-1.6) and afterwards 2.3/100 pyrs (95% CI, 1.9-2.7). TB incidence increased within 6 months followed by a stable rate over time. There was no evidence for changing risk factors for TB disease over time after miners stopped IPT. The average TB incidence rate attributable to reinfection in the first year was estimated at 1.3/100 pyrs, compared to an observed rate of 2.2/100 pyrs (95% CI, 1.8-2.7).Conclusions: The durability of protection by IPT was lost within 6-12 months in this setting with a high HIV prevalence and a high annual risk of M. tuberculosis infection. The observed rate was higher than the modelled rate, suggesting that reactivation of persistent latent infection played a role in the rapid return to baseline TB incidence. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
33. The Effect of Antiretroviral Therapy and CD4 Count on Markers of Infectiousness in HIV-Associated Tuberculosis.
- Author
-
van Halsema, Clare L., Fielding, Katherine L., Chihota, Violet N., George, Elizabeth C., Lewis, James J., Churchyard, Gavin J., and Grant, Alison D.
- Published
- 2015
- Full Text
- View/download PDF
34. Clinical Relevance of Nontuberculous Mycobacteria Isolated from Sputum in a Gold Mining Workforce in South Africa: An Observational, Clinical Study.
- Author
-
van Halsema, Clare L., Chihota, Violet N., Gey van Pittius, Nicolaas C., Fielding, Katherine L., Lewis, James J., van Helden, Paul D., Churchyard, Gavin J., and Grant, Alison D.
- Subjects
- *
ACADEMIC medical centers , *CHEST X rays , *CHI-squared test , *FISHER exact test , *HIV infections , *MEDICAL screening , *MYCOBACTERIAL diseases , *POLYMERASE chain reaction , *QUESTIONNAIRES , *RESEARCH funding , *SPUTUM , *SYMPTOMS , *RETROSPECTIVE studies , *KAPLAN-Meier estimator , *LOG-rank test , *MIXED infections , *KRUSKAL-Wallis Test - Abstract
Background. The clinical relevance of nontuberculous mycobacteria (NTM), detected by liquid more than solid culture in sputum specimens from a South African mining workforce, is uncertain. We aimed to describe the current spectrum and relevance of NTM in this population. Methods. An observational study including individuals with sputum NTM isolates, recruited at workforce tuberculosis screening and routine clinics. Symptom questionnaires were administered at the time of sputum collection and clinical records and chest radiographs reviewed retrospectively. Results. Of 232 individuals included (228 (98%) male, median age 44 years), M. gordonae (60 individuals), M. kansasii (50), and M. avium complex (MAC: 38) were the commonest species. Of 38 MAC isolates, only 2 (5.3%) were from smear-positive sputum specimens and 30/38 grew in liquid but not solid culture. MAC was especially prevalent among symptomatic, HIV-positive individuals. HIV prevalence was high: 57/74 (77%) among those tested. No differences were found in probability of death or medical separation by NTM species. Conclusions. M. gordonae, M. kansasii, and MAC were the commonest NTM among miners with suspected tuberculosis, with most MAC from smear-negative specimens in liquid culture only. HIV testing and identification of key pathogenic NTM in this setting are essential to ensure optimal treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
35. The Diagnostic Accuracy of Urine Lipoarabinomannan Test for Tuberculosis Screening in a South African Correctional Facility.
- Author
-
Hanifa, Yasmeen, Telisinghe, Lilanganee, Fielding, Katherine L., Malden, Justin L., Churchyard, Gavin J., Grant, Alison D., and Charalambous, Salome
- Subjects
- *
LIPOARABINOMANNANS , *URINALYSIS , *TUBERCULOSIS diagnosis , *MEDICAL screening , *BIOLOGICAL assay , *SYMPTOMS - Abstract
Background: We evaluated the diagnostic accuracy of the urine lipoarabinomannan (LAM) antigen detection assay (Clearview TB-ELISA) to screen for tuberculosis in a South African correctional facility. Methods: Between September 2009 and October 2010, male offenders were screened for tuberculosis (symptoms, chest radiograph, two spot sputum specimens for microscopy and culture), and urine tested for LAM. Sensitivity, specificity and predictive values of LAM were calculated using definite and probable tuberculosis combined as our gold standard. Findings: 33/871 (3.8%) participants (26% HIV-positive) had tuberculosis. Amongst HIV-positive vs. HIV-negative offenders the sensitivity and specificity of LAM was 7.1% vs. 0% and 98.5% vs. 99.8% respectively. Conclusion: Urine LAM ELISA has inadequate sensitivity for TB screening in this population. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
36. Tuberculosis Control in South African Gold Mines: Mathematical Modeling of a Trial of Community-Wide Isoniazid Preventive Therapy.
- Author
-
Vynnycky, Emilia, Sumner, Tom, Fielding, Katherine L., Lewis, James J., Cox, Andrew P., Hayes, Richard J., Corbett, Elizabeth L., Churchyard, Gavin J., Grant, Alison D., and White, Richard G.
- Published
- 2015
- Full Text
- View/download PDF
37. Tuberculosis Control in South African Gold Mines: Mathematical Modeling of a Trial of Community-Wide Isoniazid Preventive Therapy.
- Author
-
Vynnycky, Emilia, Sumner, Tom, Fielding, Katherine L., Lewis, James J., Cox, Andrew P., Hayes, Richard J., Corbett, Elizabeth L., Churchyard, Gavin J., Grant, Alison D., and White, Richard G.
- Subjects
- *
TUBERCULOSIS prevention , *ISONIAZID , *MINERAL industries , *RESEARCH funding , *ANTIRETROVIRAL agents , *RANDOMIZED controlled trials , *STATISTICAL models - Abstract
A recent major cluster randomized trial of screening, active disease treatment, and mass isoniazid preventive therapy for 9 months during 2006-2011 among South African gold miners showed reduced individual-level tuberculosis incidence but no detectable population-level impact. We fitted a dynamic mathematical model to trial data and explored 1) factors contributing to the lack of population-level impact, 2) the best-achievable impact if all implementation characteristics were increased to the highest level achieved during the trial ("optimized intervention"), and 3) how tuberculosis might be better controlled with additional interventions (improving diagnostics, reducing treatment delay, providing isoniazid preventive therapy continuously to human immunodeficiency virus-positive people, or scaling up antiretroviral treatment coverage) individually and in combination. We found the following: 1) The model suggests that a small proportion of latent infections among human immunodeficiency virus-positive people were cured, which could have been a key factor explaining the lack of detectable population-level impact. 2) The optimized implementation increased impact by only 10%. 3) Implementing additional interventions individually and in combination led to up to 30% and 75% reductions, respectively, in tuberculosis incidence after 10 years. Tuberculosis control requires a combination prevention approach, including health systems strengthening to minimize treatment delay, improving diagnostics, increased antiretroviral treatment coverage, and effective preventive treatment regimens. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
38. Evaluation of a point-of-care tuberculosis test-and-treat algorithm on early mortality in people with HIV accessing antiretroviral therapy (TB Fast Track study): study protocol for a cluster randomised controlled trial.
- Author
-
Fielding, Katherine L., Charalambous, Salome, Hoffmann, Christopher J., Johnson, Suzanne, Tlali, Mpho, Dorman, Susan E., Vassall, Anna, Churchyard, Gavin J., and Grant, Alison D.
- Subjects
- *
TUBERCULOSIS , *HIV infections , *CLINICAL trials , *MORTALITY , *ANTIRETROVIRAL agents - Abstract
Background: Early mortality for HIV-positive people starting antiretroviral therapy (ART) remains high in resource-limited settings, with tuberculosis the most important cause. Existing rapid diagnostic tests for tuberculosis lack sensitivity among HIV-positive people, and consequently, tuberculosis treatment is either delayed or started empirically (without bacteriological confirmation). We developed a management algorithm for ambulatory HIV-positive people, based on body mass index and point-of-care tests for haemoglobin and urine lipoarabinomannan (LAM), to identify those at high risk of tuberculosis and mortality. We designed a clinical trial to test whether implementation of this algorithm reduces six-month mortality among HIV-positive people with advanced immunosuppression. Methods/design: The TB Fast Track study is an open, pragmatic, cluster randomised superiority trial, with 24 primary health clinics randomised to implement the intervention or standard of care. Adults (aged =18 years) with a CD4 count of 150 cells/μL or less, who have not received any tuberculosis treatment in the last three months, or ART in the last six months, are eligible. In intervention clinics, the study algorithm is used to classify individuals as at high, medium or low probability of tuberculosis. Those classified as high probability start tuberculosis treatment immediately, followed by ART after two weeks. Medium-probability patients follow the South African guidelines for test-negative tuberculosis and are reviewed within a week, to be re-categorised as low or high probability. Low-probability patients start ART as soon as possible. The primary outcome is all-cause mortality at six months. Secondary outcomes include severe morbidity, time to ART start and cost-effectiveness. Discussion: This trial will test whether a primary care-friendly management algorithm will enable nurses to identify HIV-positive patients at the highest risk of tuberculosis, to facilitate prompt treatment and reduce early mortality. There remains an urgent need for better diagnostic tests for tuberculosis, especially for people with advanced HIV disease, which may render empirical treatment unnecessary. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
39. Tuberculosis Prevention in South Africa.
- Author
-
Knight, Gwenan M., Dodd, Peter J., Grant, Alison D., Fielding, Katherine L., Churchyard, Gavin J., and White, Richard G.
- Subjects
- *
TUBERCULOSIS prevention , *TUBERCULOSIS treatment , *TUBERCULOSIS patients , *DISEASE incidence ,TUBERCULOSIS transmission - Abstract
Background: South Africa has one of the highest per capita rates of tuberculosis (TB) incidence in the world. In 2012, the South African government produced a National Strategic Plan (NSP) to control the spread of TB with the ambitious aim of zero new TB infections and deaths by 2032, and a halving of the 2012 rates by 2016. Methods: We used a transmission model to investigate whether the NSP targets could be reached if immediate scale up of control methods had happened in 2014. We explored the potential impact of four intervention portfolios; 1) “NSP” represents the NSP strategy, 2) “WHO” investigates increasing antiretroviral therapy eligibility, 3) “Novel Strategies” considers new isoniazid preventive therapy strategies and HIV “Universal Test and Treat” and 4) “Optimised” contains the most effective interventions. Findings: We find that even with this scale-up, the NSP targets are unlikely to be achieved. The portfolio that achieved the greatest impact was “Optimised”, followed closely by “NSP”. The “WHO” and “Novel Strategies” had little impact on TB incidence by 2050. Of the individual interventions explored, the most effective were active case finding and reductions in pre-treatment loss to follow up which would have a large impact on TB burden. Conclusion: Use of existing control strategies has the potential to have a large impact on TB disease burden in South Africa. However, our results suggest that the South African TB targets are unlikely to be reached without new technologies. Despite this, TB incidence could be dramatically reduced by finding and starting more TB cases on treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
40. Tuberculosis active case finding: uptake and diagnostic yield among minibus drivers in urban South Africa.
- Author
-
Mabuto, Tonderai, Zwane, Ephraim, Chihota, Violet, Gresak, Gillian, Charalambous, Salome, Churchyard, Gavin J., and Hoffmann, Christopher J.
- Subjects
- *
TUBERCULOSIS diagnosis , *METROPOLITAN areas , *PREVENTIVE medicine , *HEALTH programs , *SYMPTOMS - Abstract
Background: Tuberculosis (TB) active case finding is a part of TB control in areas of higher TB prevalence. Congested public transportation settings may be areas of increased TB transmission. We evaluated the uptake and diagnostic yield of an active TB screening program among minibus drivers in a large public transportation facility in Johannesburg, South Africa. Methods: Over an eight month period, we intensively recruited minibus drivers for TB screening with a goal of 80% uptake among the estimated 2000 drivers. All participants were screened for TB symptoms, offered HIV testing, and had sputum collected for smear microscopy and liquid culture. Results: 686 drivers were screened for TB, representing an uptake of only 34% of all drivers (43% of the target screening). Ten drivers (1.5%) were culture positive for TB, nine of whom were sputum smear microscopy negative. Factors associated with previously undiagnosed TB included a history of incarceration (odds ratio [OR] 5.5, 95% confidence interval: 1.1, 27.3) and HIV positivity (OR 5.3, 95% confidence interval: 1.1, 26.3). Conclusions: We identified undiagnosed pulmonary TB cases among drivers but at a level that may be insufficient to justify systematic case finding in this population considering the poor uptake. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
41. Tuberculosis Vaccines and Prevention of Infection.
- Author
-
Hawn, Thomas R., Day, Tracey A., Scriba, Thomas J., Hatherill, Mark, Hanekom, Willem A., Evans, Thomas G., Churchyard, Gavin J., Kublin, James G., Bekker, Linda-Gail, and Self, Steven G.
- Subjects
- *
TUBERCULOSIS vaccines , *VACCINES , *DRUG resistance in bacteria , *MYCOBACTERIUM bovis , *BACILLUS (Bacteria) - Abstract
The article discusses tuberculosis (TB) vaccines and the importance of the inclusion of preinfection vaccines in development pipeline such as high population-level impact for TB disease control, prevention of infection, and occurrence of TB infection resistance in small percentage of population. Topics discussed include suboptimal efficacy of Mycobacterium bovis bacillus Clamette-Guérin (BCG), and factors contributing to gap in development of TB preinfection vaccines.
- Published
- 2014
- Full Text
- View/download PDF
42. Safety and Immunogenicity of H1/IC31®, an Adjuvanted TB Subunit Vaccine, in HIV-Infected Adults with CD4+ Lymphocyte Counts Greater than 350 cells/mm3: A Phase II, Multi-Centre, Double-Blind, Randomized, Placebo-Controlled Trial.
- Author
-
Reither, Klaus, Katsoulis, Lynn, Beattie, Trevor, Gardiner, Nicolene, Lenz, Nicole, Said, Khadija, Mfinanga, Elirehema, Pohl, Christian, Fielding, Katherine L., Jeffery, Hannah, Kagina, Benjamin M., Hughes, Elisabeth J., Scriba, Thomas J., Hanekom, Willem A., Hoff, Søren T., Bang, Peter, Kromann, Ingrid, Daubenberger, Claudia, Andersen, Peter, and Churchyard, Gavin J.
- Subjects
- *
TUBERCULOSIS vaccines , *IMMUNOGENETICS , *HIV-positive persons , *CD4 antigen , *LYMPHOCYTE count , *BLIND experiment , *RANDOMIZED controlled trials , *PLACEBOS - Abstract
Background: Novel tuberculosis vaccines should be safe, immunogenic, and effective in various population groups, including HIV-infected individuals. In this phase II multi-centre, double-blind, placebo-controlled trial, the safety and immunogenicity of the novel H1/IC31 vaccine, a fusion protein of Ag85B-ESAT-6 (H1) formulated with the adjuvant IC31, was evaluated in HIV-infected adults. Methods: HIV-infected adults with CD4+ T cell counts >350/mm3 and without evidence of active tuberculosis were enrolled and followed until day 182. H1/IC31 vaccine or placebo was randomly allocated in a 5∶1 ratio. The vaccine was administered intramuscularly at day 0 and 56. Safety assessment was based on medical history, clinical examinations, and blood and urine testing. Immunogenicity was determined by a short-term whole blood intracellular cytokine staining assay. Results: 47 of the 48 randomised participants completed both vaccinations. In total, 459 mild or moderate and 2 severe adverse events were reported. There were three serious adverse events in two vaccinees classified as not related to the investigational product. Local injection site reactions were more common in H1/IC31 versus placebo recipients (65.0% vs. 12.5%, p = 0.015). Solicited systemic and unsolicited adverse events were similar by study arm. The baseline CD4+ T cell count and HIV viral load were similar by study arm and remained constant over time. The H1/IC31 vaccine induced a persistent Th1-immune response with predominately TNF-α and IL-2 co-expressing CD4+ T cells, as well as polyfunctional IFN-γ, TNF-α and IL-2 expressing CD4+ T cells. Conclusion: H1/IC31 was well tolerated and safe in HIV-infected adults with a CD4+ Lymphocyte count greater than 350 cells/mm3. The vaccine did not have an effect on CD4+ T cell count or HIV-1 viral load. H1/IC31 induced a specific and durable Th1 immune response. Trial registration: Pan African Clinical Trials Registry (PACTR) [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
43. High-Dose Rifapentine with Moxifloxacin for Pulmonary Tuberculosis.
- Author
-
Jindani, Amina, Harrison, Thomas S., Nunn, Andrew J., Phillips, Patrick P. J., Churchyard, Gavin J., Charalambous, Salome, Hatherill, Mark, Geldenhuys, Hennie, McIlleron, Helen M., Zvada, Simbarashe P., Mungofa, Stanley, Shah, Nasir A., Zizhou, Simukai, Magweta, Lloyd, Shepherd, James, Nyirenda, Sambayawo, van Dijk, Janneke H., Clouting, Heather E., Coleman, David, and Bateson, Anna L. E.
- Subjects
- *
ANTITUBERCULAR agents , *TUBERCULOSIS treatment , *DRUG efficacy , *DRUG administration , *FLUOROQUINOLONES , *THERAPEUTICS - Abstract
The article presents a study as of October 2014 that highlights the need for tuberculosis regimens that are shorter and simpler than the six-month daily regimen. The study reveals the effectiveness of the six-month regimen that included weekly administration of high-dose rifapentine and moxifloxacin and the non-inferiority of the four-month regimen to the control regimen.
- Published
- 2014
- Full Text
- View/download PDF
44. Four Models of HIV Counseling and Testing: Utilization and Test Results in South Africa.
- Author
-
Mabuto, Tonderai, Latka, Mary H., Kuwane, Bulelani, Churchyard, Gavin J., Charalambous, Salome, and Hoffmann, Christopher J.
- Subjects
- *
HEALTH counseling , *DIAGNOSIS of HIV infections , *HIV prevention , *CROSS-sectional method , *MEDICAL microbiology - Abstract
Background: HIV Counseling and Testing (HCT) is the point-of-entry for pathways of HIV care and prevention. However, HCT is not reaching many who are HIV infected and this may be related to the HCT provision model. We describe HCT utilization and HIV diagnosis using four models of HCT delivery: clinic-based, urban mobile, rural mobile, and stand-alone. Methods: Using cross-sectional data from routine HCT provided in South Africa, we described client characteristics and HIV test results from information collected during service delivery between January 2009 and June 2012. Results: 118,358 clients received services at clinic-based units, 18,597; stand-alone, 28,937; urban mobile, 38,840; and rural mobile, 31,984. By unit, clients were similar in terms of median age (range 28–31), but differed in sex distribution, employment status, prior testing, and perceived HIV risk. Urban mobile units had the highest proportion of male clients (52%). Rural mobile units reached the highest proportion of clients with no prior HCT (61%) and reporting no perceived HIV risk (64%). Overall, 10,862 clients (9.3%) tested HIV-positive. Conclusions: Client characteristics varied by HCT model. Importantly, rural and urban mobile units reached more men, first-time testers, and clients who considered themselves to be at low risk for HIV. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
45. Applying Ethical Principles to International Community-Based Research: A Case Study from the Consortium to Respond Effectively to the AIDS-TB Epidemic (CREATE)
- Author
-
Kass, Nancy E., Deluca, Andrea N., Coetzee, Leonie, Slmwinga, Musonda, Churchyard, Gavin J., Ayles, Helen, Beyers, Nulda, Godfrey-Faussett, Peter, Durovni, Betina, Chaisson, Richard E., and Eldred, Lois J.
- Published
- 2014
46. Applying Ethical Principles to International Community-Based Research: A Case Study from the Consortium to Respond Effectively to the AIDS-TB Epidemic (CREATE).
- Author
-
KASS, NANCY E., DELUCA, ANDREA N., COETZEE, LEONIE, SLMWINGA, MUSONDA, CHURCHYARD, GAVIN J., AYLES, HELEN, BEYERS, NULDA, GODFREY-FAUSSETT, PETER, DUROVNI, BETINA, CHAISSON, RICHARD E., and ELDRED, LOIS J.
- Subjects
- *
AIDS prevention , *TUBERCULOSIS prevention , *CLINICAL medicine research , *EPIDEMICS , *INFORMED consent (Medical law) , *RESEARCH methodology , *PUBLIC health , *RESEARCH ethics , *RISK assessment , *SOCIAL justice , *HUMAN research subjects - Abstract
The article discusses the ethical principles forwarded in the "1979 Belmont Report" to guide research with humans. These principles are respect for individuals and their community, beneficence, and justice in public health research. Mentioned are three case studies from the Consortium to Respond Effectively to the AIDS-TB Epidemic (CREATE) which are Thibela TB, Zambia South Africa TB and HIV Reduction Study (ZAMSTAR), and TB-HIV in Rio (THRio).
- Published
- 2014
47. Durable HIV RNA resuppression after virologic failure while remaining on a first-line regimen: a cohort study.
- Author
-
Hoffmann, Christopher J, Charalambous, Salome, Grant, Alison D, Morris, Lynn, Churchyard, Gavin J, and Chaisson, Richard E
- Abstract
Adherence interventions are a recommended strategy to salvage failing antiretroviral therapy without regimen change. We assessed the durability of resuppression when using this approach. Of 300 patients who resuppressed on the same regimen (41% of all those with virologic failure), 148 (45%) remained suppressed during follow-up for a median of 2.4 years (interquartile range [IQR]: 1.1, 4.0). Resuppression can be durable following viraemia without a switch in antiretroviral therapy regimen. [ABSTRACT FROM AUTHOR]
- Published
- 2014
48. Durable HIV RNA resuppression after virologic failure while remaining on a first-line regimen: a cohort study.
- Author
-
Hoffmann, Christopher J., Charalambous, Salome, Grant, Alison D., Morris, Lynn, Churchyard, Gavin J., and Chaisson, Richard E.
- Subjects
- *
VIROLOGY , *ANTIRETROVIRAL agents , *IMMUNOSUPPRESSION , *HIV , *VIREMIA , *FOLLOW-up studies (Medicine) , *COHORT analysis - Abstract
Adherence interventions are a recommended strategy to salvage failing antiretroviral therapy without regimen change. We assessed the durability of resuppression when using this approach. Of 300 patients who resuppressed on the same regimen (41% of all those with virologic failure), 148 (45%) remained suppressed during follow-up for a median of 2.4 years (interquartile range [ IQR]: 1.1, 4.0). Resuppression can be durable following viraemia without a switch in antiretroviral therapy regimen. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
49. High Tuberculosis Prevalence in a South African Prison: The Need for Routine Tuberculosis Screening.
- Author
-
Telisinghe, Lilanganee, Fielding, Katherine L., Malden, Justin L., Hanifa, Yasmeen, Churchyard, Gavin J., Grant, Alison D., and Charalambous, Salome
- Subjects
- *
TUBERCULOSIS diagnosis , *DISEASE prevalence , *PRISONS , *HIV infections , *SYMPTOMS , *SPUTUM examination , *MICROBIAL sensitivity tests - Abstract
Background: Tuberculosis is a major health concern in prisons, particularly where HIV prevalence is high. Our objective was to determine the undiagnosed pulmonary tuberculosis (“undiagnosed tuberculosis”) prevalence in a representative sample of prisoners in a South African prison. In addition we investigated risk factors for undiagnosed tuberculosis, to explore if screening strategies could be targeted to high risk groups, and, the performance of screening tools for tuberculosis. Methods and Findings: In this cross-sectional survey, male prisoners were screened for tuberculosis using symptoms, chest radiograph (CXR) and two spot sputum specimens for microscopy and culture. Anonymised HIV antibody testing was performed on urine specimens. The sensitivity, specificity and predictive values of symptoms and investigations were calculated, using Mycobacterium tuberculosis isolated on sputum culture as the gold standard. From September 2009 to October 2010, 1046 male prisoners were offered enrolment to the study. A total of 981 (93.8%) consented (median age was 32 years; interquartile range [IQR] 27–37 years) and were screened for tuberculosis. Among 968 not taking tuberculosis treatment and with sputum culture results, 34 (3.5%; 95% confidence interval [CI] 2.4–4.9%) were culture positive for Mycobacterium tuberculosis. HIV prevalence was 25.3% (242/957; 95% CI 22.6–28.2%). Positive HIV status (adjusted odds ratio [aOR] 2.0; 95% CI 1.0–4.2) and being an ex-smoker (aOR 2.6; 95% CI 1.2–5.9) were independently associated with undiagnosed tuberculosis. Compared to the gold standard of positive sputum culture, cough of any duration had a sensitivity of 35.3% and specificity of 79.6%. CXR was the most sensitive single screening modality (sensitivity 70.6%, specificity 92.2%). Adding CXR to cough of any duration gave a tool with sensitivity of 79.4% and specificity of 73.8%. Conclusions: Undiagnosed tuberculosis and HIV prevalence was high in this prison, justifying routine screening for tuberculosis at entry into the prison, and intensified case finding among existing prisoners. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
50. Comparison of Tenofovir, Zidovudine, or Stavudine as Part of First-Line Antiretroviral Therapy in a Resource-Limited-Setting: A Cohort Study
- Author
-
Velen, Kavindhran, Lewis, James J., Charalambous, Salome, Grant, Alison D., Churchyard, Gavin J., and Hoffmann, Christopher J.
- Subjects
- *
TENOFOVIR , *AZIDOTHYMIDINE , *STAVUDINE , *COHORT analysis , *CD4 antigen , *NUCLEOSIDE reverse transcriptase inhibitors , *VIROLOGY , *VIRUS diseases - Abstract
Background: Tenofovir (TDF) is part of the WHO recommended first-line antiretroviral therapy (ART); however, there are limited data comparing TDF to other nucleoside reverse transcriptase inhibitors in resource-limited-settings. Using a routine workplace and community-based ART cohort in South Africa, we assessed single drug substitution, HIV RNA suppression, CD4 count increase, loss-from-care, and mortality between TDF, stavudine (d4T) 30 mg dose, and zidovudine (AZT). Methods: In a prospective cohort study we included ART naïve patients aged ≥17 years-old who initiated ART containing TDF, d4T, or AZT between 2007 and 2009. For analysis of single drug substitutions we used a competing-risks time-to-event analysis; for loss-from-care, mixed-effect Poisson modeling; for HIV RNA suppression, competing-risks logistic regression; for CD4 count slope, mixed-effects linear regression; and for mortality, proportional hazards modeling. Results: Of 6,196 patients, the initial drug was TDF for 665 (11%), d4T for 4,179 (68%), and AZT for 1,352 (22%). During the first 6 months of ART, the adjusted hazard ratio for a single drug substitution was 2.3 for d4T (95% confidence interval [CI]: 0.27, 19) and 5.2 for AZT (95% CI: 1.1, 23), compared to TDF; whereas, after 6 months, it was 10 (95% CI: 5.8, 18) and 4.4 (95% CI: 2.5, 7.8) for d4T and AZT, respectively. Virologic suppression was similar by agent; however, CD4 count rise was lowest for AZT. The adjusted hazard ratio for loss-from-care, when compared to TDF, was 1.5 (95% CI: 1.1, 1.9) for d4T and 1.2 (95% CI: 1.1, 1.4) for AZT. The adjusted hazard ratio for mortality, when compared to TDF, was 2.7 (95% CI: 2.0, 3.5) and 1.4 (95% CI: 1.3, 1.5) and for d4T and AZT, respectively. Discussion: In routine care, TDF appeared to perform better than either d4T or AZT, most notably with less drug substitution and mortality than for either other agent. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.