Transmission of Armillifer armillatus Ova at Snake Farm, The Gambia, West Africa

Visceral pentastomiasis caused by Armillifer armillatus larvae was diagnosed in 2 dogs in The Gambia. Parasites were subjected to PCR; phylogenetic analysis confirmed relatedness with branchiurans/crustaceans. Our investigation highlights transmission of infective A. armillatus ova to dogs and, by serologic evidence, also to 1 human, demonstrating a public health concern

Pre-treatment mortality and loss-to-follow-up in HIV-1, HIV-2 and HIV-1/HIV-2 dually infected patients eligible for antiretroviral therapy in The Gambia, West Africa

<p>Abstract</p> <p>Background</p> <p>High early mortality rate among HIV infected patients following initiation of antiretroviral therapy (ART) in resource limited settings may indicate high pre-treatment mortality among ART-eligible patients. There is dearth of data on pre-treatment mortality in ART programmes in sub-Sahara Africa. This study aims to determine pre-treatment mortality rate and predictors of pre-treatment mortality among ART-eligible adult patients in a West Africa clinic-based cohort.</p> <p>Methods</p> <p>All HIV-infected patients aged 15 years or older eligible for ART between June 2004 and September 2009 were included in the analysis. Assessment for eligibility was based on the Gambia ART guideline. Survival following ART-eligibility was determined by Kaplan-Meier estimates and predictors of pre-treatment mortality determined by Cox proportional hazard models.</p> <p>Result</p> <p>Overall, 790 patients were assessed as eligible for ART based on their clinical and/or immunological status among whom 510 (64.6%) started treatment, 26 (3.3%) requested transfer to another health facility, 136 (17.2%) and 118 (14.9%) were lost to follow-up and died respectively without starting ART. ART-eligible patients who died or were lost to follow-up were more likely to be male or to have a CD4 T-cell count < 100 cells/μL, while patients in WHO clinical stage 3 or 4 were more likely to die without starting treatment. The overall pre-treatment mortality rate was 21.9 deaths per 100 person-years (95% CI 18.3 - 26.2) and the rate for the composite end point of death or loss to follow-up was 47.1 per 100 person-years (95% CI 41.6 - 53.2). Independent predictors of pre-treatment mortality were CD4 T-cell count <100 cells/μL (adjusted Hazard ratio [AHR] 3.71; 95%CI 2.54 - 5.41) and WHO stage 3 or 4 disease (AHR 1.91; 95% CI 1.12 - 3.23). Forty percent of ART-eligible patients lost to follow-up seen alive at field visit cited difficulty with the requirement of disclosing their HIV status as reason for not starting ART.</p> <p>Conclusion</p> <p>Approximately one third of ART-eligible patients did not start ART and pre-treatment mortality rate was found high among HIV infected patients in our cohort. CD4 T-cell count <100 cells/μL is the strongest independent predictor of pre-treatment mortality. The requirement to disclose HIV status as part of ART preparation counselling constitutes a huge barrier for eligible patients to access treatment.</p

Immune Reconstitution Inflammatory Syndrome and the Influence of T Regulatory Cells: A Cohort Study in the Gambia

The factors associated with the development of immune reconstitution inflammatory syndrome in HIV patients commencing antiretroviral therapy have not been fully elucidated. Using a longitudinal study design, this study addressed whether alteration in the levels of T regulatory cells contributed to the development of IRIS in a West African cohort of HIV-1 and HIV-2 patients. Seventy-one HIV infected patients were prospectively recruited to the study and followed up for six months. The patients were categorized as IRIS or non-IRIS cases following published clinical guidelines. The levels of T regulatory cells were measured using flow cytometry at baseline and all follow-up visits. Baseline cytokine levels of IL-2, IL-6, IFN-(Gamma), TNF-(Alpha), MIP-1(Beta), IL-1, IL-12, IL-13, and IL-10 were measured in all patients

CD4 intragenic SNPs associate with HIV-2 plasma viral load and CD4 count in a community-based study from Guinea-Bissau, West Africa.

OBJECTIVES: The human genetics of HIV-2 infection and disease progression is understudied. Therefore, we studied the effect of variation in 2 genes that encode products critical to HIV pathogenesis and disease progression: CD4 and CD209. DESIGN: This cross-sectional study consisted of 143 HIV-2, 30 HIV-1 + HIV-2 and 29 HIV-1-infected subjects and 194 uninfected controls recruited from rural Guinea-Bissau. METHODS: We genotyped 14 CD4 and 4 CD209 single nucleotide polymorphisms (SNPs) that were tested for association with HIV infection, HIV-2 plasma viral load (high vs. low), and CD4 T-cell count (high vs. low). RESULTS: The most significant association was between a CD4 haplotype rs11575097-rs10849523 and high viral load [odds ratio (OR): = 2.37, 95% confidence interval (CI): 1.35 to 4.19, P = 0.001, corrected for multiple testing], suggesting increased genetic susceptibility to HIV-2 disease progression for individuals carrying the high-risk haplotype. Significant associations were also observed at a CD4 SNP (rs2255301) with HIV-2 infection (OR: = 2.36, 95% CI: 1.19 to 4.65, P = 0.01) and any HIV infection (OR: = 2.50, 95% CI: 1.34 to 4.69, P = 0.004). CONCLUSIONS: Our results support a role of CD4 polymorphisms in HIV-2 infection, in agreement with recent data showing that CD4 gene variants increase risk to HIV-1 in Kenyan female sex workers. These findings indicate at least some commonality in HIV-1 and HIV-2 susceptibility

HIV-1 subtype distribution in the Gambia and the significant presence of CRF49_cpx, a novel circulating recombinant form

Background: Detailed local HIV-1 sequence data are essential for monitoring the HIV epidemic, for maintaining sensitive sequence-based diagnostics, and to aid in designing vaccines.Results: Reported here are full envelope sequences derived from 38 randomly selected HIV-1 infections identified at a Gambian clinic between 1991 and 2009. Special care was taken to generate sequences from circulating viral RNA as uncloned products, either by limiting dilution or single genome amplification polymerase chain reaction (PCR). Within these 38 isolates, eight were subtyped as A and 18 as CRF02_AG. A small number of subtype B, C, D viruses were identified. Surprising, however, was the identification of six isolates with subtype J-like envelopes, a subtype found normally in Central Africa and the Democratic Republic of the Congo (DRC), with gag p24 regions that clustered with subtype A sequences. Near full-length sequence from three of these isolates confirmed that these represent a novel circulating recombinant form of HIV-1, now named CRF49_cpx.Conclusions: This study expands the HIV-1 sequence database from the Gambia and will provide important data for HIV diagnostics, patient care, and vaccine development

Seasonal variation in haematological and biochemical reference values for healthy young children in The Gambia

Haematological and biochemistry reference values for children are important for interpreting clinical and research results however, differences in demography and environment poses a challenge when comparing results. The study defines reference intervals for haematological and biochemistry parameters and examines the effect of seasonality in malaria transmission

Seroprevalence of hepatitis B and C virus in HIV-1 and HIV-2 infected Gambians

BACKGROUND: The prevalence of HIV/hepatitis co-infection in sub-Saharan Africa is not well documented, while both HIV and HBV are endemic in this area. OBJECTIVE: The aim of this study is to determine the seroprevalence of HBV and HCV virus in HIV-infected subjects in the Gambia. METHODS: Plasma samples from HIV infected patients (190 individuals with clinically defined AIDS and 382 individuals without AIDS) were tested retrospectively for the presence of HBV sero-markers and for serum HBV DNA, screened for HCV infection by testing for anti-HCV antibody and HCV RNA. RESULTS: HBsAg prevalence in HIV-positive individuals is 12.2%. HIV/HBV co-infected individuals with CD4 count of <200 cells µL⁻¹ have a higher HBV DNA viral load than patients with higher CD4 count (log 4.0 vs. log 2.0 DNA copies/ml, p < 0.05). Males (OR = 1.8, 95% CI: 1.0, 3.2) were more likely to be HBsAg positive than female. HCV seroprevalence was 0.9% in HIV-positive individuals. CONCLUSION: The prevalence of HBsAg carriage in HIV- infected Gambians is similar to that obtained in the general population. However co-infected individuals with reduced CD4 levels, indicative of AIDS had higher prevalence of HBeAg retention and elevated HBV DNA levels compared to non-AIDS patients with higher CD4 count

HTLV-1 in rural Guinea-Bissau: prevalence, incidence and a continued association with HIV between 1990 and 2007

<p>Abstract</p> <p>Background</p> <p>HTLV-1 is endemic in Guinea-Bissau, and the highest prevalence in the adult population (5.2%) was observed in a rural area, Caió, in 1990. HIV-1 and HIV-2 are both prevalent in this area as well. Cross-sectional associations have been reported for HTLV-1 with HIV infection, but the trends in prevalence of HTLV-1 and HIV associations are largely unknown, especially in Sub Saharan Africa. In the current study, data from three cross-sectional community surveys performed in 1990, 1997 and 2007, were used to assess changes in HTLV-1 prevalence, incidence and its associations with HIV-1 and HIV-2 and potential risk factors.</p> <p>Results</p> <p>HTLV-1 prevalence was 5.2% in 1990, 5.9% in 1997 and 4.6% in 2007. Prevalence was higher among women than men in all 3 surveys and increased with age. The Odds Ratio (OR) of being infected with HTLV-1 was significantly higher for HIV positive subjects in all surveys after adjustment for potential confounding factors. The risk of HTLV-1 infection was higher in subjects with an HTLV-1 positive mother versus an uninfected mother (OR 4.6, CI 2.6-8.0). The HTLV-1 incidence was stable between 1990-1997 (Incidence Rate (IR) 1.8/1,000 pyo) and 1997-2007 (IR 1.6/1,000 pyo) (Incidence Rate Ratio (IRR) 0.9, CI 0.4-1.7). The incidence of HTLV-1 among HIV-positive individuals was higher compared to HIV negative individuals (IRR 2.5, CI 1.0-6.2), while the HIV incidence did not differ by HTLV-1 status (IRR 1.2, CI 0.5-2.7).</p> <p>Conclusions</p> <p>To our knowledge, this is the largest community based study that has reported on HTLV-1 prevalence and associations with HIV. HTLV-1 is endemic in this rural community in West Africa with a stable incidence and a high prevalence. The prevalence increases with age and is higher in women than men. HTLV-1 infection is associated with HIV infection, and longitudinal data indicate HIV infection may be a risk factor for acquiring HTLV-1, but not vice versa. Mother to child transmission is likely to contribute to the epidemic.</p

Immunological impact of an additional early measles vaccine in Gambian children: responses to a boost at 3 years.

BACKGROUND: Measles vaccine in early infancy followed by a dose at 9 months of age protects against measles and enhances child survival through non-specific effects. Little is known of immune responses in the short or long term after booster doses. METHODS: Infants were randomized to receive measles vaccine at 9 months of age (group 1) or 4 and 9 months of age (group 2). Both groups received a boost at 36 months of age. T-cell effector and memory responses using IFN-γ ELIspot and cytokine assays and antibody titres using a haemagglutination-inhibition assay were compared at various times. RESULTS: Vaccination at 4 months of age elicited antibody and CD4 T-cell mediated immune responses .Two weeks after vaccination at 9 months of age group 2 had much higher antibody titres than group1 infants; cell-mediated effector responses were similar. At 36 months of age group 2 antibody titres exceeded protective levels but were 4-fold lower than group 1; effector and cytokine responses were similar. Re-vaccination resulted in similar rapid and high antibody titres in both groups (median 512); cellular immunity changed little. At 48 months of age group 2 antibody concentrations remained well above protective levels though 2-fold lower than group 1; T-cell memory was readily detectable and similar in both groups. CONCLUSIONS: An additional early measles vaccine given to children at 4 months of age induced a predominant CD4 T-cell response at 9 months and rapid development of high antibody concentrations after booster doses. However, antibody decayed faster in these children than in the group given primary vaccination at 9 months of age. Cellular responses after 9 months were generally insignificantly different