In the wake of brisk rainfall since June, Bangladesh is experiencing a large dengue outbreak that is unusual in its scale and seasonality, the World Health Organization (WHO) said yesterday in an outbreak notice. The group added that high temperatures and high humidity, alongside the heavy rainfall, have increased mosquito populations throughout Bangladesh, where dengue is endemic.
The WHO said the outbreak is the country's second largest since 2000, second only to a large event in 2019. As of Nov 20, the health ministry has reported 52,807 lab-confirmed cases, plus 230 related deaths, for a case fatality rate of 0.44%. The predominant serotypes are dengue virus 3, predominant since 2019, and dengue virus 4, which hadn't been reported in the country for several years.
Though all eight of Bangladesh's divisions have reported cases and deaths, the most affected one is Dhaka, which has reported 70.6% of cases and 60.4% of deaths. Much of the activity has been from the city of Dhaka, the country's largest city.
The WHO said Bangladesh's climate conditions are becoming more favorable to the transmission of dengue and other vector-borne diseases. It said factors include excessive rainfall, waterlogging, flooding, a rise in temperature, and unusual shifts in the country's traditional seasons. The WHO said Bangladesh experienced moderate rainfall in October, which is outside of the monsoon season that typically runs from May to September.
The WHO also said Bangladesh has repurposed six hospitals dedicated for COVID-19 in the city of Dhaka for managing dengue cases. Among other response efforts, the ministry and WHO have distributed 284,000 diagnostic kits to hospitals throughout the country.