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Background: Making inferences about measles distribution patterns at small area level is vital for more focal targeted intervention. However, in statistical literature, the analysis of originally collected data on one resolution with the purpose to make inferences on a different level of spatial resolution is referred to as the misalignment problem. In Namibia the measles data were available in aggregated format at regional level for the period 2005 to 2014. This leads to a spatial misalignment problem if the purpose is to make decisions at constituency level. Moreover, although data on risk covariates of measles could be obtained at constituency level, they were not available each year between 2005 and 2014. Thus, assuming that covariates were constant through the study period would induce measurement errors which might have effects on the analysis results. This paper presents a spatio-temporal model through a multi-step approach in order to deal with misalignment and measurement error. Methods: For the period 2005–2014, measles data from the Ministry of Health and Social Services (MoHSS) were analysed in two steps. First, a multi-step approach was applied to correct spatial misalignment in the data. Second, a classical measurement error model was fitted to account for measurement errors. The time effects were specified using a nonparametric formulation for the linear trend through first order random walk. An interaction between area and time was modelled through type I and type II interaction structures. Results: The study showed that there was high variation in measles risk across constituencies and as well as over the study period (2005–2014). Furthermore, the risk of measles was found to be associated with (i) the number of people aged between 0 and 24 years, (ii) the percentages of women aged 15–49 with an educational level more than secondary, (iii) the percentages of children age 12–23 months who received measles vaccine, (iv) the percentages of malnourished children under 5 years, and (vi) the measles cases for each previous year. Conclusion: The study showed some of the determinants of measles risk and revealed areas at high risk through disease mapping. Additionally, the study showed a non-linear temporal distribution of measles risk over the study period. Finally, it was shown that ignoring the measurement errors may yield misleading results. It was recommended that group and geographically targeted intervention, prevention and control strategies can be tailored on the basis these findings. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization (WHO) early warning indicators (EWIs) of HIV drug resistance (HIVDR) assess factors at individual ART sites that are known to create situations favourable to the emergence of HIVDR. Methods: In 2014, the Namibia HIV care and treatment program abstracted the following adult and pediatric EWIs from all public ART sites (50 main sites and 143 outreach sites): On-time pill pick-up, Retention in care, Pharmacy stock-outs, Dispensing practices, and Viral load suppression. Comparisons were made between main and outreach sites and between 2014 and 2012 using the Wilcoxon signed-rank test in a matched analysis. Results: The national estimates were: On-time pill pick-up 81.9% (95% CI 81.1–82.8) for adults and 82.4% (81.3–83.4) for pediatrics, Retention in care 79% retained on ART after 12 months for adults and 82% for pediatrics, Pharmacy stock-outs 94% of months without a stock-out for adults and 88% for pediatrics, and Dispensing practices 0.01% (0.001–0.056) dispensed mono- or dual-therapy for adults and 0.01% (0.001–0.069) for pediatrics. Viral load suppression was significantly affected by low rates of Viral load completion. Main sites had higher On-time pill pick-up than outreach sites for adults (p<0.001) and pediatrics (p<0.001), and no difference between main and outreach sites for Retention in care for adults (p = 0.761) or pediatrics (p = 0.214). From 2012 to 2014 in adult sites, On-time pill pick-up (p = 0.001), Retention in care (p<0.001), and Pharmacy stock-outs (p = 0.002) worsened. In pediatric sites, On-time pill pick-up (p<0.001) and Pharmacy stock-outs (p = 0.012) worsened. Conclusions: Results of EWIs monitoring in Namibia provide evidence about ART programmatic functioning and contextualize results from national surveys of HIVDR. These results are worrisome as they show a decline in program performance over time. The national ART program is taking steps to minimize the emergence of HIVDR by strengthening adherence and retention of patients on ART, reducing stock-outs, and strengthening ART data quality. [ABSTRACT FROM AUTHOR]

Background: Cryptococcal meningitis is common and associated with high mortality among HIV infected persons. The World Health Organization recommends that routine Cryptococcal antigen (CrAg) screening in ART-naïve adults with a CD4+ count <100 cells/μL followed by pre-emptive antifungal therapy for CrAg-positive patients be considered where CrAg prevalence is ≥3%. The prevalence of CrAg among HIV adults in Namibia is unknown. We estimated CrAg prevalence among HIV-infected adults receiving care in Namibia for the purpose of informing routine screening strategies. Methods: The study design was cross-sectional. De-identified plasma specimens collected for routine CD4+ testing from HIV-infected adults enrolled in HIV care at 181 public health facilities from November 2013 to January 2014 were identified at the national reference laboratory. Remnant plasma from specimens with CD4+ counts <200 cells/μL were sampled and tested for CrAg using the IMMY® Lateral Flow Assay. CrAg prevalence was estimated and assessed for associations with age, sex, and CD4+ count. Results: A total of 825 specimens were tested for CrAg. The median (IQR) age of patients from whom specimens were collected was 38 (32–46) years, 45.9% were female and 62.9% of the specimens had CD4 <100 cells/μL. CrAg prevalence was 3.3% overall and 3.9% and 2.3% among samples with CD4+ counts of CD4+<100 cells/μL and 100–200 cells/μL, respectively. CrAg positivity was significantly higher among patients with CD4+ cells/μL < 50 (7.2%, P = 0.001) relative to those with CD4 cells/μL 50–200 (2.2%). Conclusion: This is the first study to estimate CrAg prevalence among HIV-infected patients in Namibia. CrAg prevalence of ≥3.0% among patients with CD4+<100 cells/μL justifies routine CrAg screening and preemptive treatment among HIV-infected in Namibia in line with WHO recommendations. Patients with CD4+<100 cells/μL have a significantly greater risk for CrAg positivity. Revised guidelines for ART in Namibia now recommend routine screening for CrAg. [ABSTRACT FROM AUTHOR]

Background: The role of pathogen-mediated febrile illness in sub-Saharan Africa is receiving more attention, especially in Southern Africa where four countries (including Namibia) are actively working to eliminate malaria. With a high concentration of livestock and high rates of companion animal ownership, the influence of zoonotic bacterial diseases as causes of febrile illness in Namibia remains unknown. Methodology/Principal Findings: The aim of the study was to evaluate exposure to Coxiella burnetii, spotted fever and typhus group rickettsiae, and Bartonella henselae using IFA and ELISA (IgG) in serum collected from 319 volunteer blood donors identified by the Blood Transfusion Service of Namibia (NAMBTS). Serum samples were linked to a basic questionnaire to identify possible risk factors. The majority of the participants (64.8%) had extensive exposure to rural areas or farms. Results indicated a C. burnetii prevalence of 26.1% (screening titre 1∶16), and prevalence rates of 11.9% and 14.9% (screening titre 1∶100) for spotted fever group and typhus group rickettsiae, respectively. There was a significant spatial association between C. burnetii exposure and place of residence in southern Namibia (P<0.021). Donors with occupations involving animals (P>0.012), especially cattle (P>0.006), were also significantly associated with C. burnetii exposure. Males were significantly more likely than females to have been exposed to spotted fever (P<0.013) and typhus (P<0.011) group rickettsiae. Three (2.9%) samples were positive for B. henselae possibly indicating low levels of exposure to a pathogen never reported in Namibia. Conclusions/Significance: These results indicate that Namibians are exposed to pathogenic fever-causing bacteria, most of which have flea or tick vectors/reservoirs. The epidemiology of febrile illnesses in Namibia needs further evaluation in order to develop comprehensive local diagnostic and treatment algorithms. [ABSTRACT FROM AUTHOR]