BackgroundSub-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.MethodsWe 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 %).ResultsThe 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 %).ConclusionsChronic 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.

BackgroundSerological screening of pregnant women for Toxoplasma gondii-specific antibodies is not practiced as an antenatal care in Tanzania; and there is a limited data about sero-prevalence of T. gondii infection in developing countries. We therefore conducted this study to determine the sero-prevalence and factors associated with T. gondii infection among pregnant women attending antenatal care clinics in Mwanza, Tanzania.MethodsBetween 1st November 2012 and 31st May 2013 a total of 350 pregnant women attending antenatal care clinics in Mwanza were enrolled and screened for IgG and IgM antibodies against T. gondii using the ELISA technique.ResultsOf 350 pregnant women, 108 (30.9%) were sero-positive for T. gondii-specific antibodies. The risk of contracting T. gondii infection increases by 7% with each yearly increase in a woman’s age (OR=1.07, 95% CI: 1.02 - 1.11, p=0.002). The sero-positivity rate of T. gondii-specific antibodies was higher among pregnant women from the urban than those from rural communities (41.5% versus 22.0%); [OR=2.2, 95% CI; 1.4 - 3.7, p=0.001]. Likewise employed/business women were more likely to get T. gondii infection than peasants (40.0% versus 25.9%) [OR=1.9, 95% CI: 1.2 - 3.0, p=0.006].ConclusionsSero-prevalence of T. gondii-specific antibodies is high among pregnant women in Mwanza with a significant proportion of women at risk of contracting primary T. gondii infections. Screening of T. gondii infections during antenatal care should be considered in Tanzania as the main strategy to minimize congenital toxoplasmosis.

BackgroundSero-positivity rates of the rubella virus among pregnant women vary widely throughout the world. In Tanzania, rubella vaccination is not included in the national immunization schedule and there is therefore no antenatal screening for this viral disease. So far, there are no reports on the sero-prevalence of rubella among pregnant women in Tanzania. As a result, this study was undertaken to establish the sero-positivity rate of rubella and rubella risk factors among pregnant women attending antenatal care clinics in Mwanza, Tanzania.MethodsFrom November 2012 to May 2013 a total of 350 pregnant women were enrolled and their serum samples collected and analyzed using the AXSYM anti-rubella virus IgG/IgM-MEIA test. Demographic and clinical data were collected using a standardized data collection tool. Data analysis was done using STATA version 12.ResultsOf 342 pregnant women tested for rubella antibodies, 317 (92.6%) were positive for anti-rubella IgG while only 1 (0.3%) was positive for IgM. Higher sero-positivity rates were found in the age group of 25–44 years. Furthermore, it was observed that with each year increase in age, the risk of contracting rubella increases by 12% (OR = 1.12, 95% CI: 1.02-1.22, P = 0.019). Women involved in farming and business women were at a higher risk of contracting rubella infection compared to formally employed women (OR: 4.9, P = 0.011; OR 7.1, p = 0.003 respectively). In univariate analysis, the risk of contracting rubella virus infection was found to increase with gestational age with a statistical significance.ConclusionsSero-positivity rates of rubella are high in Mwanza and are significantly associated with an increase in age and being a farmer or a business woman. Screening of rubella and immunization of women at risk are highly recommended in this area with a high non-immune rate against rubella virus.

BackgroundThe World Health Organization (WHO) has recommended guidelines for a HIV drug resistance (HIVDR) survey for resource-limited countries. Eligibility criteria for patients include age below 25 years in order to focus on the prevalence of transmitted HIVDR (tHIVDR) in newly-infected individuals. Most of the participating sites across Africa have so far reported tHIVDR prevalences of below 5%. In this study we investigated whether the rate of HIVDR in patients <25 years is representative for HIVDR in the rest of the therapy-naïve population.Methods and FindingsHIVDR was determined in 88 sequentially enrolled ART-naïve patients from Mwanza, Tanzania (mean age 35.4 years). Twenty patients were aged <25 years and 68 patients were aged 25–63 years. The frequency of HIVDR in the study population was 14.8% (95%; CI 0.072–0.223) and independent of NVP-resistance induced by prevention of mother-to-child transmission programs. Patients >25 years had a significantly higher HIVDR frequency than younger patients (19.1%; 95% CI 0.095–0.28) versus 0%, P = 0.0344). In 2 out of the 16 patients with HIVDR we found traces of antiretrovirals (ARVs) in plasma.ConclusionsART-naïve patients aged over 25 years exhibited significantly higher HIVDR than younger patients. Detection of traces of ARVs in individuals with HIVDR suggests that besides transmission, undisclosed misuse of ARVs may constitute a significant factor in the generation of the observed high HIVDR rate. The current WHO tHIVDR survey that is solely focused on the transmission of HIVDR and that excludes patients over 25 years of age may therefore result in substantial underestimation of the prevalence of HIVDR in the therapy-naïve population. Similar studies should be performed also in other areas to test whether the so far reported optimistic picture of low HIVDR prevalence in young individuals is really representative for the rest of the ART-naïve HIV-infected population.

Objective Hypertension is believed to be an increasingly common driver of the epidemic of non-communicable diseases (NCDs) in sub-Saharan Africa, but prospective data are scarce. The objective of this prospective study was to determine the contribution of hypertension to deaths, admissions, and hospital days at a Tanzanian zonal hospital. Methods: Between 2009 and 2011, diagnoses were recorded for all medical admissions together with age, gender, length of hospitalization and in-hospital mortality. Results Among 11,045 consecutive admissions, NCDs accounted for nearly half of all deaths, admissions, and hospital days. Among NCDs, hypertension-related diseases were the most common and accounted for 314 (33.9%) of the total NCD deaths, 1,611 (29.9%) of the NCD admissions, and 12,837 (27.8%) NCD hospital days. Stroke (167 deaths) was the leading cause of hypertension-related death. Hypertension was the leading cause of death in patients over the age of 50 years and 57% of hypertension-related deaths occurred in patients <65 years old. Conclusion NCDs account for half of all deaths, admissions and hospital days at our Tanzanian hospital and hypertension-related diseases were the most common NCD. Hypertension accounted for 34% of NCD deaths and 15% of all deaths. Hypertension was the second most common cause of death overall and the leading cause of death in patients >50 years old. More than half of hypertension-related deaths occurred before retirement age. These findings have important implications for public health and medical education in sub-Saharan Africa, where hypertension and related diseases have not traditionally been given a high priority.