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Abstract The ongoing vaccination efforts and exposure to endemic and emerging coronaviruses can shape the population's immunity against this group of viruses. In this study, we investigated neutralizing immunity against endemic and emerging coronaviruses in 200 Tanzanian frontline healthcare workers (HCWs). Despite low vaccination rates (19.5%), we found a high SARS-CoV-2 seroprevalence (94.0%), indicating high exposure in these HCWs. Next, we determined the neutralization capacity of antisera against human coronavirus NL63, and 229E, SARS-CoV-1, MERS-CoV and SARS-CoV-2 (including Omicron subvariants: BA.1, BQ.1.1 and XBB.1.5) using pseudovirus neutralization assay. We observed a broad range of neutralizing activity in HCWs, but no neutralization activity detected against MERS-CoV. We also observed a strong correlation between neutralizing antibody titers for SARS-CoV-2 and SARS-CoV-1, but not between other coronaviruses. Cross-neutralization titers against the newer Omicron subvariants, BQ.1.1 and XBB.1.5, was significantly reduced compared to BA.1 and BA.2 subvariants. On the other hand, the exposed vaccinated HCWs showed relatively higher median cross-neutralization titers against both the newer Omicron subvariants and SARS-CoV-1, but did not reach statistical significance. In summary, our findings suggest a broad range of neutralizing potency against coronaviruses in Tanzanian HCWs with detectable neutralizing immunity against SARS-CoV-1 resulting from SARS-CoV-2 exposure.

BackgroundTanzania has made significant progress in improving access to HIV care and treatment. However, virologic suppression among people living with HIV (PLHIV) has not been fully realized. In March 2019, Tanzania introduced a World Health Organization (WHO)-recommended dolutegravir-based regimen as the default first-line regimen. Eighteen months later we investigated the HIV viral suppression rates and the factors associated with lack of viral suppression among PLHIV (children and adults) in Tanzania.MethodologyA cross-sectional survey was conducted from September to December 2020 among PLHIV on antiretroviral therapy (ART) in Tanzania. Whole blood samples, demographic data and clinical information were obtained from eligible adults (≥15 years) and children (< 15 years) attending thirty-six HIV care and treatment centres located in 22 regions of Tanzania mainland. A whole blood sample from each participant was processed into plasma and HIV viral load was estimated using real-time PCR. HIV viral suppression was defined at a cut-off of < 50 copies/mL as recommended by WHO. Analyses were conducted using descriptive statistics to establish the national representative prevalence of viral suppression, and logistic regression analyses to determine independent factors associated with non-suppression.ResultsA total of 2,039 PLHIV on ART were recruited; of these, adults and children were 57.5% (n = 1173) and 42.5% (n = 866), respectively. Among the adult population, the mean age and standard deviation (SD) was 42.1 ± 12.4 years, with 64.7% being female. Among children, the mean age and SD were 9.6 ± 3 years, and 53.2% were female. Overall viral suppression at < 50 copies/mL (undetectable) was achieved in 87.8% of adults and 74.4% of children. Adults and children on dolutegravir-based regimen recorded viral suppression rates of 89.7% and 85.1% respectively. Factors independently associated with lack of viral suppression status in the adult population were age and ART adherence while in the children population, the factors were sex, ART adherence, and current ART regimen (pConclusionDolutegravir-based regimens are promising to help attain epidemic control in Tanzania. More efforts especially on ART adherence are needed to attain optimal treatment outcomes for children and adults PLHIV in Tanzania.

BackgroundFor successful HIV response, updated information on the burden and progress toward HIV elimination targets are required to guide programmatic interventions. We used data from the 2020 HIV sentinel surveillance to update on the burden and factors associated with HIV infection, HIV status awareness, and ART coverage among pregnant women in Tanzania mainland.MethodologyWe conducted the surveillance in 159 antenatal clinics (ANC) from all 26 regions of Tanzania's mainland from September to December 2020. This cross-sectional study included all pregnant women (≥15 years) on their first ANC visit in the current pregnancy during the survey period. Routine HIV counselling and testing were done at the facility. A multivariable logistic regression model accounting for the survey design was used to examine factors associated with HIV infections.Results38,783 pregnant women were enrolled (median age (IQR) = 25 (21-30) years). HIV prevalence was 5.9% (95%CI: 5.3% - 6.6%), ranging from 1.9% in the Manyara region to 16.4% in the Njombe region. Older age, lower and no education, not being in a marital union, and living in urban or semi-urban areas were associated with higher odds of HIV infection. HIV status awareness among women who tested positive was 70.9% (95% CI: 67.5%- 74.0%). ART coverage among those aware of their status was 91.6% (86.5%- 94.9%). Overall, 66.6% (95% CI: 62.4%- 70.6%) of all pregnant women who tested positive for HIV knew their HIV status and were on ART.ConclusionHIV is increasingly prevalent among pregnant women in Tanzania mainland especially among older, those with lower or no formal education, those outside marital union, and pregnant women living in urban and semi-urban areas. Behind the global fast-target to end HIV/ AIDS, about a third of pregnant women living with HIV initiating ANC were not on ART. Interventions to increase HIV testing and linkage to care among women of reproductive age should be intensified.

Background Syphilis has detrimental effects on the health of the mother and that of both fetuses and newborns exposed in utero or at delivery. Understanding its local epidemiology is essential for policies, planning, and implementation of targeted preventive interventions. Using data from the 2020 National Sentinel Surveillance of pregnant women attending antenatal clinics (ANCs) in Tanzania we determined the prevalence and determinants of syphilis among pregnant women in Tanzania mainland. Methodology The ANC surveillance was conducted in 159 ANC sites from all 26 regions of Tanzania’s mainland from September to December 2020. It included all pregnant women 15 years and above on their first ANC visit in the current pregnancy during the survey period. Counseling for syphilis was done using standard guidelines at the ANC and testing was done using rapid SD Bioline HIV/Syphilis Duo test kits. Analysis was done using both descriptive statistics to determine the prevalence and characteristics of syphilis, whereas, logistic regressions were used to examine the independent association between syphilis and dependent variables. Results A total of 38,783 women [median age (Interquartile range (IQR)) = 25 (21–30) years] participated in the surveillance. Of them, 582 (1.4%) tested positive for syphilis. A wide regional variation was observed with the highest burden in Kagera (4.5%) to the lowest burden in Kigoma (0.3%). The odds of syphilis infections were higher among older women and those with no formal education. Compared with primigravids, women with 1–2, those with 3–4 and those with more than four previous pregnancies had 1.8 (aOR = 1.8, 95% CI: 1.2–2.5), 2.1 (aOR = 2.1, 95% CI: 1.4–3.1) and 2.6 (aOR = 2.6, 95% CI: 1.7–3.9) higher odds of syphilis infection respectively. Conclusion Syphilis is still prevalent among pregnant women in Tanzania with a wide regional disparity. Efforts to prevent new infections, screen pregnant women, and treat those infected should be strategized to include all regions and renewed emphasis on regions with high burden, and importantly among women who are multipara, with a low level of education, and advanced age.

BackgroundThe emergence of HIV drug resistance mutations (DRMs) is of significant threat to achieving viral suppression (VS) in the quest to achieve global elimination targets. We hereby report virologic outcomes and patterns of acquired DRMs and its associated factors among adolescents and young adults (AYA) from a broader HIV drug resistance surveillance conducted in Tanzania.MethodsData of AYA was extracted from a cross-sectional study conducted in 36 selected facilities using a two-stage cluster sampling design. Dried blood spot (DBS) samples were collected and samples with a viral load (VL) ≥1000 copies/mL underwent genotyping for the HIV-1 pol gene. Stanford HIV database algorithm predicted acquired DRMs, Fisher's exact test and multivariable logistic regression assessed factors associated with DRMs and VS, respectively.FindingsWe analyzed data of 578 AYA on antiretroviral therapy (ART) for 9-15 and ≥ 36 months; among them, 91.5% and 88.2% had VS (VLConclusionsVS amongst AYA is lower than the third UNAIDs target. Additionally, a high prevalence of ADR and high levels of circulating clinically relevant DRMs may compromise the long-term VS in AYA. Furthermore, the first VL result of ≥1000copies/ml after ART initiation is a significant risk factor for developing DRMs. Thus, strict VL monitoring for early identification of treatment failure and genotypic testing during any ART switch is recommended to improve treatment outcomes for AYA.

Background The emergence of HIV drug resistance mutations (DRMs) is of significant threat to achieving viral suppression (VS) in the quest to achieve global elimination targets. We hereby report virologic outcomes and patterns of acquired DRMs and its associated factors among adolescents and young adults (AYA) from a broader HIV drug resistance surveillance conducted in Tanzania. Methods Data of AYA was extracted from a cross-sectional study conducted in 36 selected facilities using a two-stage cluster sampling design. Dried blood spot (DBS) samples were collected and samples with a viral load (VL) ≥1000 copies/mL underwent genotyping for the HIV-1 pol gene. Stanford HIV database algorithm predicted acquired DRMs, Fisher’s exact test and multivariable logistic regression assessed factors associated with DRMs and VS, respectively. Findings We analyzed data of 578 AYA on antiretroviral therapy (ART) for 9–15 and ≥ 36 months; among them, 91.5% and 88.2% had VS (VLConclusions VS amongst AYA is lower than the third UNAIDs target. Additionally, a high prevalence of ADR and high levels of circulating clinically relevant DRMs may compromise the long-term VS in AYA. Furthermore, the first VL result of ≥1000copies/ml after ART initiation is a significant risk factor for developing DRMs. Thus, strict VL monitoring for early identification of treatment failure and genotypic testing during any ART switch is recommended to improve treatment outcomes for AYA.