ABSTRACT
Background: Anti-SARS-CoV-2 antibody tests are increasingly used for sero-epidemiological purposes to provide a better understanding of the extent of the infection in the community, and to monitor the progression of the COVID-19 epidemic. A sero-prevalence study was conducted to estimate prior infections with SARS-CoV-2 in Addis Ababa. Methods: A cross-sectional study was conducted from April 23 to 28, 2020 among 301 randomly selected residents of Addis Ababa;sub-city health offices, health facilities and health extension workers were contacted, to obtain a population profile and to conduct the random selection of study participants. Participants were selected, who had not been in direct contact with people who had contracted COVID-19, to maintain consistency among the study population. Interviews on socio demographic and behavioural risk factors, followed by serological tests were performed for SARS-CoV-2 IgM, and IgG antibodies, using the COVID-19 IgG/IgM Rapid Test Cassette. Based on the manufacturer information, the test has a sensitivity of 87.9% and specificity of 100% for IgM;and a sensitivity of 97.2% and specificity of 100% for IgG. A Polymerase chain reaction (RT-PCR) test was also done on combined nasopharyngeal and oropharengeal swabs. Findings: The unadjusted antibody-based crude SARS-CoV-2 prevalence was 7.6% and the adjusted (weighted average) SARS-CoV-2 prevalence was estimated at 8.8% (95% CI 5.5%-11.6%) for the study population. Higher sero-prevalence were observed for males (9.0%), age below 50 years (8.2%), students and unemployed (15.6%), as well as those with primary education (12.1%), educated above high school (37.9%), non- smokers (78.7%), with no history of regular alcohol (53.8%), no chat (70.8%), and no shisha use (94.7%). According to the findings, a significantly higher number of individuals had been infected in Addis Ababa as compared to what was being detected and reported by the RT-PCR test, which is suggestive of community transmission.
ABSTRACT
Background: An outbreak of "pneumonia of unknown etiology" later renamed as Novel Corona Virus (COVID 19) was first reported from Hubei Province, China on 31 December 2019. The cases have increased exponentially;the pandemic has reached all countries in the world with 81.2 million confirmed cases and over 1.8 million by December 28, 2020. Ethiopia reported its first case on March 13, 2020, and as of December 28, 2020, the country had 122864 confirmed COVID-19 cases and 1909 deaths. Being a new pandemic its epidemiologic trajectories across regions and populations remains unknown. Mathematical models are widely used to understand and predict the possible courses of an outbreak, given a set of underlying assumptions. Objective: This study intends to model COVID 19 epidemic trajectory under different assumptions and to predict the likely timing of peak of the epidemic in Ethiopia. Methods: Standard Susceptible Exposed, Infected and Recovery (SEIR) compartmental epidemiological deterministic model was employed to estimate and predict COVID 19 in progression in Ethiopia and Addis Ababa at different points of time. Exhaustive literature reviews were carried out to contextualize COVID 19 pandemic epidemiological. Efficacy and coverage of face mask and social distancing were considered in the best and worst situation to run the model and estimate the number of infections after sustained local transmissions. Result. Without any intervention, the COVID 19 viruses spread will peak at 150 days from the first report, infecting 8.01million people given local/community transmission. As the compliance with face mask coverage increases by 25%, 50%, and 75%, the infection will be reduced by about 20%, 40%, and 60% respectively social distancing compliance by le 25% of the population alone will reduce above 60% of infections. Compliance of 40% face mask use and social distance combined effect will reduce 97% of the estimated number of cases. Conclusion: This predication indicated that compliance with combination of non-pharmaceutical intervention such as use of face mask use with physical distance averted significant number of COVID infection. For a county like Ethiopia with poor health systems resilience, mitigating the pandemic at an early stage through strong preventive measures is necessary.