Seroprevalence of Toxoplasma gondii infection among pregnant women in Windhoek, Namibia, in 2016.

BACKGROUND: When a pregnant woman contracts Toxoplasma gondii (T. gondii) infection during pregnancy, it may be vertically transmitted to the foetus. Information on the incidence of congenital toxoplasmosis (CT) in developing countries is scarce. Most studies focus on the seroprevalence of T. gondii infection among pregnant women. This study aimed to determine the seroprevalence of T. gondii infection among pregnant women attending public antenatal care in Windhoek, Namibia, in 2016. METHODS: In this descriptive study, 344 urban pregnant women attending public antenatal care were voluntarily enrolled in the study. Seroprevalence of anti-T. gondii Immunoglobulin G (IgG) was determined by automated immunoassay. Samples with a positive T. gondii IgG result were tested for T. gondii Immunoglobulin M (IgM) and specific IgG avidity by using an enzyme-linked immunosorbent assay (ELISA) test. A questionnaire captured demographic data and exposure to risk factors. Data were analysed using Statistical Package for the Social Sciences (SPSS) and R. RESULTS: Anti-T. gondii IgG was found in nine (2.61%) pregnant women. There was no association of anti-T. gondii IgG with demographic characteristics or exposure to risk factors.Anti-T. gondii IgM was positive in one (0.3%) woman, while three (0.9%) women had borderline anti-T. gondii IgM results. Specific IgG avidity was low, equivocal and high in 0%, 33% and 67% of seropositive pregnant women, respectively. CONCLUSION: Seroprevalence of anti-T. gondii IgG is much lower in Namibia than is reported in other developing countries. Investigation into specific IgM seropositivity and IgG avidity showed that pregnant women in the central region of Namibia are at low risk of vertical transmission and development of CT.

Profile, perceptions and future expectations of medical laboratory scientists in Namibia.

Background: Public healthcare systems in sub-Saharan Africa are challenged by healthcare worker shortages, loss of trained staff and attrition to the private sector. Studies have historically focused on medical doctors, nurses and pharmacists, with limited focus on medical laboratory scientists. Objectives: This study addresses the professional perspectives and expectations of the first two classes of biomedical science students, who graduated from the Polytechnic of Namibia in 2012 and 2013. Methods: A questionnaire was developed to capture qualitative and quantitative data from fourth-year students completing their final semester. Data collected included: demographic information; students' experience; professional expectations; and perceptions about the future of biomedical science education in Namibia. Results: Amongst the 42 of 45 enrolled students who completed the questionnaire, nearly two-thirds anticipated working in government hospitals (29%) or industry (35%), with fewer planning careers in private hospitals (12%) or academia (14%). Most expressed an interest in working abroad (64%) and/or in the capital (64%), with fewer interested in small urban areas (48%). Only 7% expressed interest in working in a rural area. Regarding their view of the future of biomedical science in Namibia, 38% responded that it was encouraging, whereas the rest responded that it was uncertain (52%), negative (2%) or unknown (7%). Conclusion: Members of the first graduating classes of Namibia's nascent Biomedical Science degree programme reported a perceived lack of opportunity for professional advancement in the field if they remained in Namibia. Continued thought needs to be given to develop sustainable strategies and opportunities to retain Namibian biomedical laboratory scientists in Namibia.

Exposure and risk factors to coxiella burnetii, spotted fever group and typhus group Rickettsiae, and Bartonella henselae among volunteer blood donors in Namibia.

BACKGROUND: The role of pathogen-mediated febrile illness in sub-Saharan Africa is receiving more attention, especially in Southern Africa where four countries (including Namibia) are actively working to eliminate malaria. With a high concentration of livestock and high rates of companion animal ownership, the influence of zoonotic bacterial diseases as causes of febrile illness in Namibia remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: The aim of the study was to evaluate exposure to Coxiella burnetii, spotted fever and typhus group rickettsiae, and Bartonella henselae using IFA and ELISA (IgG) in serum collected from 319 volunteer blood donors identified by the Blood Transfusion Service of Namibia (NAMBTS). Serum samples were linked to a basic questionnaire to identify possible risk factors. The majority of the participants (64.8%) had extensive exposure to rural areas or farms. Results indicated a C. burnetii prevalence of 26.1% (screening titre 1∶16), and prevalence rates of 11.9% and 14.9% (screening titre 1∶100) for spotted fever group and typhus group rickettsiae, respectively. There was a significant spatial association between C. burnetii exposure and place of residence in southern Namibia (P<0.021). Donors with occupations involving animals (P>0.012), especially cattle (P>0.006), were also significantly associated with C. burnetii exposure. Males were significantly more likely than females to have been exposed to spotted fever (P<0.013) and typhus (P<0.011) group rickettsiae. Three (2.9%) samples were positive for B. henselae possibly indicating low levels of exposure to a pathogen never reported in Namibia. CONCLUSIONS/SIGNIFICANCE: These results indicate that Namibians are exposed to pathogenic fever-causing bacteria, most of which have flea or tick vectors/reservoirs. The epidemiology of febrile illnesses in Namibia needs further evaluation in order to develop comprehensive local diagnostic and treatment algorithms.

Risk assessment of flavivirus transmission in Namibia.

The role of arboviruses causing acute febrile illness in sub-Saharan Africa is receiving more attention. Reports of dengue in tourists were published nearly 10 years ago in Namibia, but the current epidemiology of arboviruses is unknown and surveys of mosquito vectors have not been carried out since the 1950s. To begin addressing this knowledge gap, a prospective cross-sectional study was conducted using samples from volunteer blood donors linked to questionnaire. Serum samples were tested using a Dengue IgG Indirect ELISA which measured exposure to dengue virus/flaviviruses. Entomological samples were collected from tires during the rainy season (February-March 2012) in six locations across Namibia's capital city, Windhoek. Among 312 blood donors tested, 25 (8.0%) were positive for dengue virus/flavivirus exposure. The only significant risk factor was age group with high exposure rates among those older than 50 (29%) compared with those below 40 years old (between 2.9% and 8.3%) (P<0.002). Larvae and pupae of Aedes aegypti and Culex pipiens complex accounted for 100% of the 2751 samples collected, of which only 12.2% (n=336) were Ae. aegypti. Each site demonstrated high variability of species composition between sampling times. While the significant dengue virus/flavivirus exposure rate among those above 50 years old is likely indicative of the West Nile epidemic in the 70s and 80s, the low exposure among those under 50 suggests that flaviviruses are still circulating in Namibia. While Ae. aegypti and C. pipiens sp. may play a role in future epidemics, the significance of presence may be reduced due to short rain periods, dry, arid, cold winters and policies and social understandings that limit non-structured storage and use of tires in low income areas. Future studies should further characterize the circulating arboviruses and investigate mosquito ecology nationally to map areas at higher risk for future arbovirus outbreaks.

Neglected tropical diseases of Namibia: unsolved mysteries.

Neglected tropical diseases (NTDs) are diseases most commonly found in settings of poverty and are responsible for the morbidity and/or mortality of millions each year. As an upper-middle income country, Namibia is not normally considered to have many NTDs but published reports indicate the possible presence of over 30. Because much of the data is buried in historical studies published before Independence in 1990, there is a risk of losing valuable information on which to build current and future integrated public health strategies. The purpose of this review, therefore, is to bring together these significant fragments to identify existing knowledge gaps which need to be addressed to build effective control, prevention, and even elimination strategies. The review focuses on intestinal helminthes, schistosomes/snail 'vectors', viruses (Rift Valley Fever, Crimean Congo Hemorrhagic Fever, rabies), protozoa (Leishmania, Toxoplasma, Amoeba, Giardia), bacteria (Rickettsia, Ehrlichia, Leptospira, Coxiella, Brucella, and Borrelia), fungi (Pneumocystis) and myiasis. Each NTD speaks to the possible need for surveillance and the creation of integrated disease risk maps, linking prevalence of related NTDs with environmental and ecological factors to assist control and prevention efforts. The predominance of zoonotic disease suggests a need to integrate veterinary and public health components as the national public health surveillance system is established.