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The detection of vaccine-induced HIV antibody responses by rapid diagnostic tests (RDTs) may confound the interpretation of HIV testing results. We assessed the impact of vaccine-induced seroreactivity (VISR) on the diagnosis of HIV in sub-Saharan Africa. Samples collected from healthy participants of HIVIS and TaMoVac HIV vaccine trials after the final vaccination were analyzed for VISR using HIV testing algorithms used in Mozambique and Tanzania that employ two sequential RDTs. The samples were also tested for VISR using Enzygnost HIV Integral 4 ELISA and HIV western blot assays. Antibody titers to subtype C gp140 were determined using an in-house enzyme-linked immunosorbent assay (ELISA). The frequency of VISR was 93.4% (128/137) by Enzygnost HIV Integral 4 ELISA, and 66.4% (91/137) by western blot assay (WHO interpretation). The proportion of vaccine recipients that would have been misdiagnosed as HIV-positive in Mozambique was half of that in Tanzania: 26.3% (36/137) and 54.0% (74/137), respectively, p < 0.0001. In conclusion, the HIV RDTs and algorithms assessed here will potentially misclassify a large proportion of the HIV vaccine recipients if no other test is used. Increased efforts are needed to develop differential serological or molecular tools for use at the point of care. [ABSTRACT FROM AUTHOR]

Background: Febrile illness is the commonest cause of hospitalization in children <5 years in sub-Saharan Africa, and bacterial bloodstream infections and malaria are major causes of death. Methods: From March 2017 to July 2018, we enrolled 2,226 children aged 0–5 years hospitalized due to fever in four major public hospitals of Dar es Salaam, namely, Amana, Temeke, and Mwananyamala Regional Hospitals and Muhimbili National Hospital. We recorded social demographic and clinical data, and we performed blood-culture and HIV-antibody testing. We used qPCR to quantify Plasmodium falciparum parasitaemia and Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) to identify bacterial isolates. Disk diffusion method was used for antimicrobial susceptibility testing. Results: Nineteen percent of the children (426/2,226) had pathogens detected from blood. Eleven percent (236/2,226) of the children had bacteraemia/fungaemia and 10% (204/2,063) had P. falciparum malaria. Ten children had concomitant malaria and bacteraemia. Gram-negative bacteria (64%) were more frequent than Gram-positive (32%) and fungi (4%). Over 50% of Gram-negative bacteria were extended-spectrum beta-lactamase (ESBL) producers and multidrug resistant. Methicillin resistant Staphylococcus aureus (MRSA) was found in 11/42 (26.2%). The most severe form of clinical malaria was associated with high parasitaemia (>four million genomes/μL) of P. falciparum in plasma. Overall, in-hospital death was 4% (89/2,146), and it was higher in children with bacteraemia (8%, 18/227) than malaria (2%, 4/194, p = 0.007). Risk factors for death were bacteraemia (p = 0.03), unconsciousness at admission (p < 0.001), and admission at a tertiary hospital (p = 0.003). Conclusion: Compared to previous studies in this region, our study showed a reduction in malaria prevalence, a decrease in in-hospital mortality, and an increase in antimicrobial resistance (AMR) including ESBLs and multidrug resistance. An increase of AMR highlights the importance of continued strengthening of diagnostic capability and antimicrobial stewardship programs. We also found malaria and bacteraemia contributed equally in causing febrile illness, but bacteraemia caused higher in-hospital death. The most severe form of clinical malaria was associated with P. falciparum parasitaemia. [ABSTRACT FROM AUTHOR]

Some evidence suggests that aflatoxin may contribute to the high prevalence of stunting observed in low‐income countries. Whereas several studies have been conducted in West Africa, fewer exist in East Africa and even fewer in nonagricultural contexts. We analyzed serum samples from 400 iron‐replete, nonanemic pregnant women from a cohort in Dar es Salaam, Tanzania to determine the extent and magnitude of exposure to aflatoxin and to study the relationship between levels of aflatoxin exposure in utero and infant birth and growth outcomes. Ninety‐nine percent of women had detectable concentrations of aflatoxin B1‐lysine (AFB1‐lysine), with a median level of 1.4‐pg/mg albumin, indicating a much lower level compared to studies of rural populations in sub‐Saharan Africa. Our results do not show a statistically significant relationship between AFB1‐lysine levels and birth weight, small for gestational age, or prematurity. We observe a small statistically significant reduction in gestational age at delivery (0.47 weeks; 95% CI: −0.86, −0.07) as the natural log of AFB1‐lysine levels increases by 1 unit of pg/mg of albumin, after controlling for potential confounders. Among a nonrandom set of infants who had measurements for placental weight, haemoglobin at delivery, and follow‐up z‐score measurements, we find no association between aflatoxin plasma concentrations and these variables. These findings suggest a high prevalence of chronic low‐level exposure to aflatoxin, though its effect on birth outcomes in this population remains unclear. Our research adds to a growing body of literature finding mixed associations between aflatoxins on pregnancy outcomes and child growth. [ABSTRACT FROM AUTHOR]

OBJECTIVE Nine out of ten tuberculosis deaths occur in tuberculosis-burdened countries, particularly Sub Saharan Africa. In these setting mortality has not been fully described. We describe the magnitude and pattern of TB mortality in Tanzania. METHODS A multicenter prospective cohort study was conducted among HIV infected and uninfected pulmonary tuberculosis patients from time of anti-TB treatment initiation to completion. Patients were censored at the time of treatment completion, or at their last visit for those who did not complete TB treatment. Kaplan-Meier curves were used to estimate time to death; cox proportional hazards model was used to examine risk factors for mortality. RESULTS A total of 58 deaths out of 1696 patients (3.4%) occurred, two thirds (n = 39) during the first two months of treatment. Compared to HIV un-infected TB patients, mortality risk for TB/HIV co-infected patients was least when antiretroviral therapy (ART) was initiated after 14 days of anti-TB (RR = 3.55; 95% CI: 1.44, 8.73 p < 0.0001) and highest when ART was initiated 90 days or less prior to anti-TB and within the first 14 days of anti-TB therapy (RR = 10; 95% CI: 3.28, 30.54; p < 0.0001). CONCLUSION Meticulously planned and supervised antiretroviral therapy reduces mortality among TB/HIV patients. Among patients with TB/HIV naïve of ART, withholding ART until the third week of anti-tuberculosis therapy will likely reduce TB mortality in Tanzania. Patients on ART and later develop tuberculosis should be closely monitored. [ABSTRACT FROM AUTHOR]