Epidemiology of 1,375 Cases of COVID-19 in Selangor

Introduction The first case of Coronavirus Disease (COVID-19) in Malaysia was reported on the 25th of January 20201. Basic epidemiology remains the cornerstone of identifying the distribution of diseases, and the source of an infection. This study aims to describe the epidemiological characteristics of the first 1,375 positive cases of COVID-19 reported in the state of Selangor, Malaysia. Materials and Methods All laboratory confirmed positive cases of COVID-19, based on RT-PCR testing from Nasopharyngeal Swabs reported in Selangor up to 25th of April 2020 were included. The epidemic curve was based on the date of onset of symptoms, or their date of exposure for asymptomatic patients. A second plot was done based on the date of onset, asymptomatic cases based on date of exposure plus median incubation period. Results 1375 positive COVID-19 cases were reported in Selangor. The mean age was 38•6 ± 18•3 years. • 36•4% of patients were asymptomatic. Fever (66•1%), and cough (56•0%) being the most common symptoms. The median incubation period was 6 (IQR: 3 – 10) days. Discussion Screening based on symptoms is inadequate in capturing all cases in the community. • Limiting human-to-human transmission remains crucial in containing this disease. This supports the findings of modelling studies which predicted a decline to occur two weeks after travel restrictions