ABSTRACT
Background: As of October 26, 2020, Malawi reported 5,894 confirmed COVID-19 cases with 183 deaths. A state of disaster was declared in March;however, a strict lockdown order was never issued. Malawi has implemented a testing strategy involving screening and testing only symptomatic persons due to limited availability of tests. Sentinel surveillance was conducted with the primary purpose of estimating the prevalence of symptomatic and asymptomatic SARS-CoV-2 infection among children >5 years and adults in Malawi health facilities (HF). Methods: SARS-CoV-2 surveillance was conducted at 14 purposively selected HFs across 8 districts in all 3 regions of Malawi from August 27 to October 14, 2020. Persons entering HFs were screened for COVID-19 symptoms;all those with symptoms suggestive of COVID-19 per Malawi guidelines and a systematic sample of asymptomatic individuals were invited to participate. Questionnaire data and nasopharyngeal swabs were collected from consenting persons. Infection was confirmed by SARS-CoV-2 RT-PCR assay (Abbott m2000). This preliminary analysis was restricted to those with test results. We performed chisquare tests to assess bivariate associations between demographic or behavioral characteristics and SARS-CoV-2 status stratified by symptom status. Results: A total of 8,169 (1,350 symptomatic, 6,819 asymptomatic) individuals were enrolled. Results are currently available for 1,300 (96%) symptomatic and 6,648 (97%) asymptomatic participants. A total of 30 (2%) symptomatic and 37 (0.6%) asymptomatic participants tested SARS-CoV-2 positive (Table). Most (67%) positive symptomatic participants were aged 15-49 years, followed by 50+ years (30%);a similar trend was seen for asymptomatic cases. A higher percentage of symptomatic cases reported being in contact with a confirmed or suspected COVID-19 case than symptomatic non-cases (p=.03). Among positive symptomatic individuals, the most common symptom was cough (70%);fever and loss of smell or taste were reported in 13% and 10% of individuals, respectively. Most COVID-19 cases in both symptom groups reported not adhering to social distancing guidelines. Conclusion: Based on preliminary data, asymptomatic SARS-CoV-2 infection in Malawians visiting HFs was relatively rare. This suggests a need for continued surveillance to ensure a better understanding of exposures as well as further monitoring of SARs-CoV-2 transmission in Malawi.