Background We explored whether hospital-based surveillance is useful in detecting severe acute respiratory infection (SARI) clusters and how often these events result in outbreak investigation and community mitigation. Methods During May 2009– December 2020, physicians at 14 sentinel hospitals prospectively identified SARI clusters (i.e., ≥2 SARI cases who developed symptoms ≤10 days of each other and lived <30 minute walk or <3 km from each other). Oropharyngeal and nasopharyngeal swabs were tested for influenza and other respiratory viruses by rRT-PCR. We describe the demographic of persons within clusters, laboratory results, and outbreak investigations. Results Physicians identified 464 clusters comprising 1,427 SARI cases (range 0–13 clusters per month). Sixty percent of clusters had three, 23% had 2, and 17% had ≥4 cases. Their median age was 2 years (interquartile [IQR] 0.4–25) and 63% were male. Laboratory results were available for the 464 clusters a median 9 days (IQR = 6–13 days) after cluster identification. Less than one in five clusters had cases that tested positive for the same virus: RSV in 58 (13%), influenza viruses in 24 (5%), HMPV in 5 (1%), HPIV in 3 (0.6%), adenovirus in 2 (0.4%). While 102/464 (22%) had poultry exposure, none tested positive for influenza A(H5N1) or A(H7N9). None of the 464 clusters led to field deployments for outbreak response. Conclusions For 11 years, none of the hundreds of identified clusters led to emergency response. The value of this event-based surveillance might be improved by seeking larger clusters, with stronger epidemiologic ties or decedents.

The coronavirus disease 19 (COVID-19) is a highly transmissible respiratory disease affecting millions of people worldwide. We summarized the current status of COVID-19 outbreaks in Bangladesh. Since the first COVID-19 confirmed case in Bangladesh on 8 March 2020, 7667 cases and 168 deaths were reported until 30 April 2020. Most cases (54%) were detected in the capital city Dhaka. Bangladesh Government declared 41 days shutdown, starting from 26 March 2020 to reduce the transmission of this highly contagious respiratory disease. Likewise, in other COVID-19 affected countries, the increasing trend of COVID-19 positive cases was continuing. People of Bangladesh are highly vulnerable to this disease mainly because of high population density, poor hygienic practice, unnecessary mobility, limited access to the hospitals, and insufficient ICU (intensive care unit) facilities. The government should focus on widespread laboratory testing and rapid response to prevent further spread of SARS-CoV-2 virus.