Mosquitoes

Rise in dengue cases possibly due to weakened herd immunity

More than 3,000 cases of dengue infections have already been reported over the last four months this year, nearly exceeding the total number of cases reported in the whole year of 2018.

“As the number of dengue infections was considerably low in the past three years, the risk of an individual being exposed to the virus is also lower, which could have resulted in weakened herd immunity due to natural infection over time”, said Assistant Professor Vincent Pang, Director, Centre for Infectious Disease Epidemiology and Research.

“If the number of dengue cases increases to a level where herd immunity is ineffective to limit the transmission (potentially due to increase in proportion of new predominant serotypes), there is a high risk that the total number of dengue infections will increase exponentially.”

While everyone has an equal risk of being infected, the disease is more severe in elderly with weaker immune systems, as well as individuals with diabetes and hypertension. Everyone should do their part to take regular self-protection measures and prevent mosquito breeding sites, in order to limit the spread of the virus.