Epidemiological Characteristics of COVID-19 Confirmed Cases in Muscat Governorate, Sultanate of Oman

Introduction: The coronavirus disease 2019 (COVID-19) was declared as pandemic by WHO by March 11th. First case reported in Oman was on 24th February 2020 and later the country went through stages of epidemic progression. This study describes the sociodemographic and epidemiological characteristics of confirmed COVID-19 cases in Muscat governorate and related outcomes. Materials and Methods: This is a descriptive, exploratory analysis of all lab confirmed COVID 19 cases that were reported from 1st February to 31st May 2020. Data for the study was primarily extracted from notifications system established for surveillance (Tarassud). Secondary data sources were, contact listings and hospital medical records. Results: 11,648 initial cases of confirmed COVID-19 infections were included. The mean age was 35 years, 84.7% (N = 9862) were males, 25.9% (N = 3017) were Omanis, and 74.1% (N = 8631) were expatriates of which Indian origin were the majority (37%). Fever and cough were the most common presentations (46.3% and 29.5% respectively). Diabetes and hypertension were the most common comorbidities (4.9% and 4.6% respectively). Hospital admission was required for 7% (N = 811) of the total reported cases, out of them 171 cases (21%) were admitted to ICU, where 107 (13.2%) were ventilated. The case fatality rate (CFR) was 0.9%. 158 clusters containing 2949 contacts were identified from case records and categorised into 3 groups based on their exposure settings. The incubation period measured was 8 days (IQR 4.0 - 15.0) for workplace, 8 days (IQR 4 - 17) for dormitory and 4 days (IQR 2.0 - 7.0) for family groups. The secondary attack rate (SAR) estimated was 41.6% (95% CI: 0.34 - 0.48), 52% (95% CI: 0.40 - 0.63) and 33% (95% CI: 0.27 - 0.38) for workplace, dormitory and family groups, respectively. Conclusion: Results of this study, determine the transmission trend of COVID-19 in a country with high immigrant population. These findings could be utilised for further response planning in similar settings.