TY - JOUR A1 - Nyawale, Helmut A. A1 - Moremi, Nyambura A1 - Mohamed, Mohamed A1 - Njwalila, Johnson A1 - Silago, Vitus A1 - Krone, Manuel A1 - Konje, Eveline T. A1 - Mirambo, Mariam M. A1 - Mshana, Stephen E. T1 - High seroprevalence of SARS-CoV-2 in Mwanza, northwestern Tanzania: a population-based survey JF - International Journal of Environmental Research and Public Health N2 - The transmission of the SARS-CoV-2 virus, which causes COVID-19, has been documented worldwide. However, the evidence of the extent to which transmission has occurred in different countries is still to be established. Understanding the magnitude and distribution of SARS-CoV-2 through seroprevalence studies is important in designing control and preventive strategies in communities. This study investigated the seropositivity of the SARS-CoV-2 virus antibodies in the communities of three different districts in the Mwanza region, Tanzania. A household cross-sectional survey was conducted in September 2021 using the modified African Centre for Disease and Prevention (ACDC) survey protocol. A blood sample was obtained from one member of each of the selected households who consented to take part in the survey. Immunochromatographic rapid test kits were used to detect IgM and IgG SARS-CoV-2 antibodies, followed by descriptive data analysis. Overall, 805 participants were enrolled in the study with a median age of 35 (interquartile range (IQR):27–47) years. The overall SARS-CoV-2 seropositivity was 50.4% (95%CI: 46.9–53.8%). The IgG and IgM seropositivity of the SARS-CoV-2 antibodies was 49.3% and 7.2%, respectively, with 6.1% being both IgG and IgM seropositive. A history of runny nose (aOR: 1.84, 95%CI: 1.03–3.5, p = 0.036), loss of taste (aOR: 1.84, 95%CI: 1.12–4.48, p = 0.023), and living in Ukerewe (aOR: 3.55, 95%CI: 1.68–7.47, p = 0.001) and Magu (aOR: 2.89, 95%CI: 1.34–6.25, p= 0.007) were all independently associated with SARS-CoV-2 IgM seropositivity. Out of the studied factors, living in the Ukerewe district was independently associated with IgG seropositivity (aOR 1.29, CI 1.08–1.54, p = 0.004). Twenty months after the first case of COVID-19 in Tanzania, about half of the studied population in Mwanza was seropositive for SARS-CoV-2. KW - SARS-CoV-2 KW - COVID-19 KW - seroprevalence KW - antibodies KW - Mwanza KW - Tanzania Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288134 SN - 1660-4601 VL - 19 IS - 18 ER - TY - JOUR A1 - Reusch, Julia A1 - Wagenhäuser, Isabell A1 - Gabel, Alexander A1 - Eggestein, Annika A1 - Höhn, Anna A1 - Lâm, Thiên-Trí A1 - Frey, Anna A1 - Schubert-Unkmeir, Alexandra A1 - Dölken, Lars A1 - Frantz, Stefan A1 - Kurzai, Oliver A1 - Vogel, Ulrich A1 - Krone, Manuel A1 - Petri, Nils T1 - Influencing factors of anti-SARS-CoV-2-spike-IgG antibody titers in healthcare workers: A cross-section study JF - Journal of Medical Virology N2 - Against the background of the current COVID-19 infection dynamics with its rapid spread of SARS-CoV-2 variants of concern (VOC), the immunity and the vaccine prevention of healthcare workers (HCWs) against SARS-CoV-2 continues to be of high importance. This observational cross-section study assesses factors influencing the level of anti-SARS-CoV-2-spike IgG after SARS-CoV-2 infection or vaccination. One thousand seven hundred and fifty HCWs were recruited meeting the following inclusion criteria: age ≥18 years, PCR-confirmed SARS-CoV-2 infection convalescence and/or at least one dose of COVID-19 vaccination. anti-SARS-CoV-2-spike IgG titers were determined by SERION ELISA agile SARS-CoV-2 IgG. Mean anti-SARS-CoV-2-spike IgG levels increased significantly by number of COVID-19 vaccinations (92.2 BAU/ml for single, 140.9 BAU/ml for twice and 1144.3 BAU/ml for threefold vaccination). Hybrid COVID-19 immunized respondents (after infection and vaccination) had significantly higher antibody titers compared with convalescent only HCWs. Anti-SARS-CoV-2-spike IgG titers declined significantly with time after the second vaccination. Smoking and high age were associated with lower titers. Both recovered and vaccinated HCWs presented a predominantly good humoral immune response. Smoking and higher age limited the humoral SARS-CoV-2 immunity, adding to the risk of severe infections within this already health impaired collective. KW - anti‐SARS‐CoV‐2‐spike IgG KW - seroprevalence KW - SARS‐CoV‐2 infection KW - healthcare workers KW - COVID‐19 vaccination Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318659 VL - 95 IS - 1 ER - TY - JOUR A1 - Mueller, A. A1 - Stoetter, L. A1 - Kalluvya, S. A1 - Stich, A. A1 - Majinge, C. A1 - Weissbrich, B. A1 - Kasang, C. T1 - Prevalence of hepatitis B virus infection among health care workers in a tertiary hospital in Tanzania JF - BMC Infectious Diseases N2 - Background: Sub-Saharan Africa has a high prevalence of hepatitis B virus (HBV) infections. Health care workers (HCWs) are at high risk of contracting HBV infection through their occupation. Vaccination of HCWs against HBV is standard practice in many countries, but is often not implemented in resource-poor settings. We aimed with this cross-sectional study to determine HBV prevalence, HCW vaccination status, and the risk factors for HCWs contracting HBV infection in Tanzania. Methods: We enrolled 600 HCWs from a tertiary Tanzanian hospital. Their demographics, medical histories, HBV vaccination details and risk factors for contracting blood-borne infections were collected using a standardized questionnaire. Serum samples were tested for HBV and hepatitis C virus (HCV) markers by ELISA techniques, PCR and an anti-HBs rapid test. HCWs were divided in two subgroups: those at risk of contracting HBV (rHCW 79.2 %) via exposure to potentially infectious materials, and those considered not at risk of contracting HBV (nrHCW, 20.8 %). Results: The overall prevalence of chronic HBV infection (HBsAg+, anti-HBc+, anti-HBs-) was 7.0 % (42/598). Chronic HBV infection was found in 7.4 % of rHCW versus 5.6 % of nrHCW(p-value = 0.484). HCWs susceptible to HBV (HBsAg-, anti-HBc-, anti-HBs-) comprised 31.3 %. HBV immunity achieved either by healed HBV infection (HBsAg-, anti-HBc+, anti-HBs+) or by vaccination (HBsAg-, anti-HBc-, anti-HBs+) comprised 36.5 % and 20.2 %, respectively. 4.8 % of participants had indeterminate results (HBsAg-, anti-HBc+, anti-HBc-IgM-, anti-HBs-). Only 77.1 % of HCWs who received a full vaccination course had an anti-HBs titer > 10 ml/U. An anti-HBs point-of-care test was 80.7 % sensitive and 96.9 % specific. There was a significantly higher risk for contracting HBV (anti-HBc+) among those HCW at occupational risk (rHCW) of older age (odds ratios (OR) in rHCW 3.297, p < 0.0001 vs. nrHCW 1.385, p = 0.606) and among those HCW being employed more than 11 years (OR 2.51, p < 0.0001***). HCV prevalence was low (HCV antibodies 1.2 % and HCV-RNA 0.3 %). Conclusions: Chronic HBV infection is common among Tanzanian HCWs. One third of HCWs were susceptible to HBV infection, highlighting the need for vaccination. Due to high prevalence of naturally acquired immunity against HBV pre-testing might be a useful tool to identify susceptible individuals. KW - hepatitis C virus KW - point-of-care test KW - human-immunodeficiency-virus KW - C virus KW - seroprevalence KW - syphilis KW - vaccine KW - Uganda KW - blood KW - hepatitis B virus KW - health care workers KW - Tanzania Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-141786 VL - 15 IS - 386 ER -