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Dengue (DEN) is a semi-neglected and dangerously re-emerging, mosquito-borne viral disease of the Flaviviridae family. Dengue virus (DENV) has been rapidly spreading for the past 6 decades, and now affects more than 50% the world’s population, especially the tropical and subtropical countries. DENV transmission and geographic expansion is expected to rise due to increased international travels, deforestation, industrialization, urbanization and climatic changes. A major control strategy for dengue is achieved through targeting the mosquito vectors, which put a significant break in the transmission of DENV to humans. For long, most dengue endemic nations relied heavily on chemical control measures, however, there were growing concerns and controversies on cases of multiple insecticide resistance. Therefore, more research interest has shifted toward studies on the use of biological control, biotechnological approaches, as potential alternatives. Indeed, dengue prevention is a key, mainly through continuous search for novel vaccines and/or improves on the potency, effectiveness, efficacy, safety, and affordability of existing ones, in order to assure protection against all serotypes of dengue, regardless of age, sex or race of people. In this chapter, we outlined and elucidated available non-insecticide based dengue control strategies that have been implemented, and/or currently being tested. We also updated information on currently licensed dengue vaccines, those in clinical trials and their public health prospects in the prevention of dengue.

Non-Polio Enteroviruses (NPEVs) are in circulation all over the world. Some of these viruses have been associated with several chronic diseases such as cardiopathy, myositis, acute flaccid and spastic paralysis in children which mimic poliomyelitis. This study sought to ascertain whether Non-Polio Enteroviruses (NPEVs) are silently shed by apparently healthy school children in Bauchi state, Nigeria. This cross-sectional study involved 200 stool samples collected from 170 (85%) vaccinated and 30 (15%) unvaccinated apparently healthy school children from Bauchi, Katagum and Misau local government areas of Bauchi state, Nigeria. All samples were processed and inoculated onto Rhabdomyosarcoma (RD) and L20B cell-lines. Inoculated cell-lines were monitored for Cytopathic Effects (CPE) for 10 days with 1 subculture after first 5 days. None of the samples came down with CPE on L20B however, three (3) samples were positive for NPEVs on RD cell lines. One (1) coxsackie B virus was from a 7 years old male child, and 2 other untypeable isolated were from a male and a female child respectively. All the 3 (1.6%) positive samples were from children not immunized with Oral Polio Vaccine (OPV). The coxsackie B virus was identified by micro neutralization test using polyclonal sera as described by the World Health Organization. Findings from this study indicate the presence of relatively few NPEVs in the study participants. Since NPEVs can implicate persistent fecal-oral transmission and present with serious pathology, it should be considered as serious public health issue. This justifies the need for periodic surveillance of NPEVs in our communities in order to prevent unforeseen NPEVs-associated diseases and promote public health policies that will encourage environmental sanitation programs.

Background: Nigeria is one of the dengue hyper-endemic nations. This study investigated the level of knowledge about dengue and vector preventive practices and their impacts on acute dengue among febrile patients at Abuja, Nigeria. Materials and methods: This cross-sectional survey was conducted on febrile patients attending University of Abuja Teaching Hospital, Abuja, Nigeria. Blood samples were individually collected from 171 febrile patients residing at Gwagwalada suburb. Interviewer administered questionnaires were used to assess subjects’ knowledge about preventive measures against vector breeding and bites. Blood samples were tested for dengue virus Nonstructural glycoprotein-1antigen using enzyme linked Immunosorbent assay (ELISA). Results: Fifteen out of 171 febrile persons (8.8%) were Dengue NS1 positive. Sixty percent of the subjects do not know about dengue, while 33% knew about dengue virus infection through television/ radio programs, 5% through healthcare professionals and 2% from friends/families. Those who persistently use indoor residual spraying and long sleeves/trousers during daytime had less cases of DENV NS1 than those who do not. There was statistical association between DENV NS1 and residence in proximity to waste dumpsites (P0.05). Conclusions: Findings from this study imply that proper education and adherence to preventive measures minimize people from being susceptible to Dengue virus infections.

Background: This cross-sectional study evaluated Apoptotic Protease Activating Factor and cluster of differentiation-4+ (CD4+) T-cell counts in patients infected with Mycobacterium tuberculosis in Bauchi, Nigeria. Methods: This involved 180 blood samples from 90 tuberculosis (TB)-infected patients and 90 of their close contacts at home or attending Federal Medical Center Azare and Infectious Disease Hospital Bayara, Bauchi, Nigeria. The blood samples were analyzed for Apoptotic Protease Activating Factor (Apaf-1) expression using ELISA and CD4+ T cells using cyflow counter. Structured questionnaires were also used to collect the sociodemographic and clinical data of the study participants. Results: Eighty-six of the TB-infected patients had pulmonary TB (PTB), two had spine TB, and two had pleural TB. No statistically significant difference was recorded in CD4+ T-cell counts (P = 0.2935) between participants with PTB (mean ± standard deviation [SD]: 680.4 ± 235 cells/mm3) and those with extra-PTB (mean ± SD: 553.0 ± 130.5 cells/mm3). Similarly, there was no significant difference in Apaf-1 concentration (P = 0.1432) between participants with PTB (mean ± standard error of the mean [SEM]: 320.3 ± 35.4 pg/ml), and participants with extra-PTB (mean ± SEM: 143.7 ± 7.8 pg/ml). No significant difference was recorded in CD4+ T-cell counts (P = 0.4299) between the participants on treatment (mean ± SD: 758.6 ± 358.6 cells/mm3) and those who are treatment naïve (mean ± SD: 637.7 ± 208.4 cells/mm3). Similarly, there was no significant difference in Apaf-1 concentration (P = 0.6829) between the study participants on treatment (mean ± SEM: 336.3 ± 34.7 pg/ml) and those who are not on treatment (mean ± SEM: 381.2 ± 176.8 pg/ml). The CD4+ T-cells count was significantly higher in the controls (866.7 ± 288.4 cells/mm3) compared to the TB (675.0 ± 232.7 cells/mm3) patients (P < 0.0001). However, there was no significant difference in Apaf-1 expression between the control (312.4 ± 34.6 pg/ml) and the TB patients (329.1 ± 44.0 pg/ml) (P = 0.7658). Conclusion: Findings from this study showed a lower T-cell immune function during TB infection. However, Apaf-1 has no relevance on TB progression and control.

Prompt and accurate laboratory testing of women before or during antenatal days is necessary for detecting humoral immunological responses against cytomegalovirus (CMV) infection and assessing risk of congenital transmission. CMV is the most common viral etiology with the greatest propensity to induce neonatal pathologies. Most healthcare facilities in developing countries rely solely on anti-CMV IgM and IgG assays in diagnosing CMV infections. However, these parameters have some worrisome limitations. This study reviewed the significance of IgG avidity testing as a highly sensitive and specific tool that improves decisions regarding diagnosis of maternal and congenital CMV infections. We conducted this review from relevant published articles using an extensive literature search made through PubMed, Scopus and Google scholar on the concepts of congenital CMV (CCMV) transmission and clinical significance of IgG avidity testing in diagnosis of CCMV infections. Findings from our review revealed that IgG avidity testing in some developed societies was frequently utilized to resolve dilemmas associated with serodiagnosis of CMV infections, however, there is paucity of information in regards to its use in developing countries. The non-inclusion of IgG avidity testing during serological investigations of CMV could be a reason why congenital CMV infections and associated pathologies often go underdiagnosed in developing countries.

Introduction: Poliovirus infections have been established to be in circulation in the remaining three polio-endemic nations. These pathogens have been associated with several chronic diseases, particularly acute flaccid paralysis of children. This study sought to ascertain whether polioviruses are silently shed by apparently healthy schoolchildren in Bauchi, Katagum, and Misau local government areas of Bauchi state, Nigeria. Methodology: This was a cross-sectional prospective study that involved 200 stool samples collected from apparently healthy schoolchildren. All samples were processed and inoculated onto rhabdomyosarcoma (RD) and L20B cell-lines. Inoculated cell lines were monitored for cytopathic effects (CPEs) for 10 days with one subculture after first 5 days. Results: None of the samples came down with CPEs on L20B, and thus all samples were negative for poliovirus; however, three were positive for non-polio enteroviruses (NPEVs) on RD and not on the L20B cell line: one coxsackie B virus from a seven-year-old male, and two others were untypeable isolates, one each from a male and a female child. The coxsackie B virus was identified by microneutralization test using polyclonal sera as described by the World Health Organization. Conclusions: Findings from this investigation indicate the absence of polioviruses in the children studied. This is an indication of good polio immunization coverage in these communities. However, more intensive and periodic surveillance is required to confirm the presence or exclude the absence of polioviruses in these communities and other parts of Nigeria.

Background Individuals with human T-cell lymphotrophic virus type-1 (HTLV-1)/HIV-1 coinfection have been demonstrated to undergo CD4+ lymphocytosis even in the face of immunodeficiency and increased vulnerability to opportunistic pathogens that can lead to poor prognosis. Objective This study investigated the prevalence as well as the effects of HIV-1/HTLV-1 coinfection on CD4+ cell counts, routine hematology, and biochemical parameters of study participants. Materials and Methods This prospective cross-sectional study involved 184 blood samples collected from HIV-1-seropositive individuals attending HIV-special clinic of the University of Abuja Teaching Hospital, Gwagwalada, Nigeria. These samples were analyzed for anti-HTLV-1/2 IgM antibodies using enzyme-linked immunosorbent assay, CD4+ cell counts, and some routine hematological and biochemical parameters. All samples were also tested for HTLV-1 provirus DNA using real-time polymerase chain reaction (PCR) assay. Results Of the 184 subjects studied, 9 (4.9%) were anti-HTLV-1/2 IgM seropositive; however, upon real-time PCR testing, 12 (6.5%) had detectable HTLV-1 provirus DNA. The CD4+ cell count was significantly high in HTLV-1-positive (742 ± 40.2) subjects compared to their HTLV-1-negative (380 ± 28.5) counterpart ( P-value = 0.025). However, there was no significant association between HTLV-1 positivity with other hematology and biochemical parameters studied ( P > 0.05). Conclusion All subjects (100%) who were HTLV-1/HIV-1-coinfected had normal CD4+ counts. This gives contrasting finding on the true extent of immunodeficiency of subjects. So it is suggested to be very careful in using only CD4+ counts to monitor disease progression and as indicators for antiretroviral therapy (ART) in resource-limited settings. In such conditions, there may be a need to test for HTLV-1 alongside HIV viral loads in order to begin appropriate ART regimens that contain both pathogens.

Background: Malaria is a widely explored public health topic which has been documented to constitute more burden among communities residing in proximity to environmental waste dumpsites and poor drainage systems. Objective: This present study sets to examine and compare whether there are more cases of malaria parasitemia burden among people residing proximal and those not proximal to dump sites at Gwagwalada metropolis. Materials and Methods: This was a cross-sectional comparative survey which involved 100 blood samples collected from 25 households proximal to environmental waste dumpsites (test subjects) and another 100 from 25 households that are not proximal to dumpsites (control subjects) in Gwagwalada metropolis of Federal Capital Territory Abuja. These samples were analyzed using standard malaria microscopy. Results: Prevalence of malaria parasitemia was 82.0% among test subjects and 26.0% among control subjects. The highest malaria density recorded was >10,000 parasites/μL in 34 test subjects whereas none was observed from control subjects. Malaria parasitemia among test subjects was common among children (1-10 years) and least among 41-50 years. There was statistical relationship between malaria parasitemia among residents proximal to environmental waste dumpsites, more so with their age distribution (P 0.05). Conclusion: The findings of this study are a clear demonstration that accumulation of waste dumpsites in proximity to residential areas constitutes a pathway to malaria burden, consequently dumpsites should be properly located and managed to minimize their effects on the environment and health of man.