Laboratory and field evaluation of the STANDARD Q and Panbio™ SARS-CoV-2 antigen rapid test in Namibia using nasopharyngeal samples.

BACKGROUND: As new SARS-CoV-2 variants of concern emerge, there is a need to scale up testing to minimize transmission of the Coronavirus disease 2019 (COVID-19). Many countries especially those in the developing world continue to struggle with scaling up reverse transcriptase polymerase reaction (RT-PCR) to detect SARS-CoV-2 due to scarcity of resources. Alternatives such as antigen rapid diagnostics tests (Ag-RDTs) may provide a solution to enable countries scale up testing. METHODS: In this study, we evaluated the Panbio™ and STANDARD Q Ag-RDTs in the laboratory using 80 COVID-19 RT-PCR confirmed and 80 negative nasopharyngeal swabs. The STANDARD Q was further evaluated in the field on 112 symptomatic and 61 asymptomatic participants. RESULTS: For the laboratory evaluation, both tests had a sensitivity above 80% (Panbio™ = 86% vs STANDARD Q = 88%). The specificity of the Panbio™ was 100%, while that of the STANDARD Q was 99%. When evaluated in the field, the STANDARD Q maintained a high specificity of 99%, however the sensitivity was reduced to 56%. CONCLUSION: Using Ag-RDTs in low resource settings will be helpful in scaling-up SARS-CoV-2 testing, however, negative results should be confirmed by RT-PCR where possible to rule out COVID-19 infection.

The role of Namibia Field Epidemiology and Laboratory Training Programme in strengthening the public health workforce in Namibia, 2012-2019.

Namibia faces a critical shortage of skilled public health workers to perform emergency response operations, preparedness activities and real-time surveillance. The Namibia Field Epidemiology and Laboratory Training Programme (NamFELTP) increases the number of skilled public health professionals and strengthens the public health system in Namibia. We describe the NamFELTP during its first 7 years, assess its impact on the public health workforce and provide recommendations to further strengthen the workforce. We reviewed disease outbreak investigations and response reports, field projects and epidemiological investigations conducted during 2012-2019. The data were analysed using descriptive methods such as frequencies and rates. Maps representing the geographical distribution of NamFELTP workforce were produced using QGIS software V.3.2. There were no formally trained field epidemiologists working in Namibia before the NamFELTP. In its 7 years of operation, the programme graduated 189 field epidemiologists, of which 28 have completed the Advanced FELTP. The graduates increased epidemiological capacity for surveillance and response in Namibia at the national and provincial levels, and enhanced epidemiologist-led outbreak responses on 35 occasions, including responses to outbreaks of human and zoonotic diseases. Trainees analysed data from 51 surveillance systems and completed 31 epidemiological studies. The NamFELTP improved outcomes in the Namibia's public health systems; including functional and robust public health surveillance systems that timely and effectively respond to public health emergencies. However, the current epidemiological capacity is insufficient and there is a need to continue training and mentorship to fill key leadership and strategic roles in the public health system.

Ecology and epidemiology of rabies in humans, domestic animals and wildlife in Namibia, 2011-2017.

Rabies is a fatal zoonotic disease that causes a heavy burden on societies. Namibia, a country in southern Africa, is aiming at controlling the disease in its main reservoir, the domestic dog. To facilitate the implementation comprehensive information on the ecology and epidemiology of the disease and surveillance is of utmost importance. The study presented assesses the baseline data for both human and animal rabies surveillance in Namibia in recent times and establishes correlations with ecological and socio-economic data in order to provide an up-to-date picture on the epidemiology of rabies in Namibia. For instance, it was important to identify the main drivers in the epidemiology, and whether the control strategy by mass vaccination of dogs is undermined by cycles of rabies in wildlife. Rabies in humans was reported mainly from the Northern Communal Areas (NCAs), with a total of 113 cases from 2011 to 2017, representing an incidence of between 1.0 and 2.4 annual human rabies deaths per 100,000 inhabitants. Kavango, the region with the highest human rabies incidence was also the region with the lowest animal rabies surveillance intensity. Generally, the vast majority (77%) of dog samples originated from communal farm land, followed by urban areas (17%), while only a small fraction (3%) was submitted from freehold farm areas. In contrast, kudu and eland submissions were almost exclusively from freehold farmland (76%) and urban areas (19%), whereas the submission of cattle samples was evenly distributed among freehold farms (46%) and communal farm land (46%). The likelihood of sample submission decreased exponentially with distance to one of the two laboratories. Overall, 67% (N = 1,907) of all samples submitted tested rabies-positive, with the highest positivity rate observed in kudus (89%) and jackals (87%). The transmission cycle of rabies in dogs appears restricted to the northern communal areas of Namibia, whilst rabies in wildlife species is predominately reported from farmland in central Namibia, mostly affecting kudu (Tragelaphus strepsiceros) and livestock with a likely reservoir in wildlife canids such as jackals or bat-eared foxes. The analysis confirms the presence of two independent transmission cycles in Namibia with little geographic overlap, thus allowing for a sustainable control of rabies in dogs in the NCAs.

An outbreak of schistosomiasis in a primary school in Omusati region, Namibia, March, 2016.

Schistosomiasis is endemic in some parts of northern Namibia and there is a control program in the country with the use of mass drug administration to control and prevent the disease. On the 1st March, 2016, there was a report of bloody urine among primary school pupils in a school in Omusati region, Namibia. A team of health professionals was dispatched to investigate. This case study describes steps in conducting a schistosomiasis outbreak investigation and how to determine the risk factors. This describes how to calculate both the basic and analytical measures of association with 95% confidence intervals. This case study provides a step-by-step approach and can be used as a tool to teach the fundamental principles of outbreak investigation and response and how to measure the appropriate measures of association. This case study is targeted at intermediate- and advanced-level residents of the Field Epidemiology and Laboratory Training Program and other epidemiology trainees.

Development of the World Health Organization Measles Programmatic Risk Assessment Tool Using Experience from the 2009 Measles Outbreak in Namibia.

In the World Health Organization (WHO) African region, reported measles cases decreased by 80% and measles mortality declined by 88% during 2000-2012. Based on current performance trends, however, focused efforts will be needed to achieve the regional measles elimination goal. To prioritize efforts to strengthen implementation of elimination strategies, the Centers for Disease Control and Prevention and WHO developed a measles programmatic risk assessment tool to identify high-risk districts and guide and strengthen program activities at the subnational level. This article provides a description of pilot testing of the tool in Namibia using comparisons of high-risk districts identified using 2006-2008 data with reported measles cases and incidence during the 2009 outbreak. Of the 34 health districts in Namibia, 11 (32%) were classified as high risk or very high risk, including the district of Engela where the outbreak began in 2009. The district of Windhoek, including the capital city of Windhoek, had the highest overall risk score-driven primarily by poor population immunity and immunization program performance-and one of the highest incidences during the outbreak. Other high-risk districts were either around the capital district or in the northern part of the country near the border with Angola. Districts categorized as high or very high risk based on the 2006-2008 data generally experienced high measles incidence during the large outbreak in 2009, as did several medium- or low-risk districts. The tool can be used to guide measles elimination strategies and to identify programmatic areas that require strengthening.