Characterization of the SARS-CoV-2 outbreak in the State of Qatar, February 28-April 18, 2020

Objective To define the epidemiologic curve of COVID-19 in Qatar, determine factors associated with severe or critical illness, and study the temporal relation between public health measures and case finding Design Epidemiologic investigation Setting and Participants All confirmed COVID-19 cases in the State of Qatar between February 28 and April 18, 2020 Main Outcome Measures Number of total and daily new COVID-19 infections; demographic characteristics and comorbidity burden and severity of infection; factors associated with severe or critical illness Results Between February 28 and April 18, 2020 (11:00AM local time), 5,685 cases of COVID-19 were identified. Mean age (SD) was 35.8(12.0) years, 88.9% were male and 8.7% were Qatari nationals. Overall, 83.6% had no concomitant comorbidity, and 3.0% had 3 or more comorbidities. The overwhelming majority (90.9%) were asymptomatic or with minimal symptoms, with 2.0% having severe or critical illness. Presence of hypertension or diabetes were associated with a higher risk of severe or critical illness. Seven deaths were observed during the time interval studied. The epidemiologic curve indicated two distinct patterns of infection, a larger cluster among expatriate craft and manual workers, and a smaller one among Qatari nationals returning from abroad during the epidemic. Conclusion COVID-19 infections in Qatar started in two distinct clusters, but then became more widespread in the population through community transmission. Infections were mostly asymptomatic or with minimal symptoms and associated with very low mortality. Severe/critical illness was associated with presence of hypertension or diabetes.