The monsoon season has created the perfect storm, as dengue cases surge primarily among children in several states across India. Dengue fever is a viral disease transmitted by infected Aedes aegypti mosquitoes in tropical and subtropical regions; while the monsoon season typically sees some cases of dengue, cases have risen sharply this year. The outbreak first emerged at the start of this month in India’s most populous state, Uttar Pradesh, but cases have since been detected in the nearby state of Madhya Pradesh.

Although up-to-date infection and mortality data are unavailable for the region, it is estimated that at least 12,000 people have contracted dengue fever in the district of Firozabad in Uttar Pradesh alone. Given the severity of this outbreak further exacerbated by the ongoing Covid-19 pandemic, GlobalData epidemiologists expect the number of diagnosed incident cases of dengue to markedly increase over the next one to two years.

As an emerging infectious disease, the global incidence of dengue has increased rapidly over the past few decades. In India, GlobalData epidemiologists forecast that the diagnosed incident cases of dengue are expected to narrowly exceed 41,000 cases by the end of this year. Since this is the worst outbreak in many years, however, the number of diagnosed incident cases will likely surpass the current forecast estimate. The sudden increase in dengue hospitalisations will likely challenge an already strained health system, with the past few months having seen drastic shortages in medical equipment and hospital bed availability due to the Covid-19 pandemic.

The main strategy to control the spread of dengue is vector control, which aims to reduce the size of mosquito populations. Around 25,000 mosquitofish have been released into ponds and lakes in Western Uttar Pradesh. Each mosquitofish can eat up to 150 larvae in only eight hours. It is important that this is complemented by an intensified environmental management strategy to destroy any potential breeding sites, such as the removal of any container that can collect water.

Some districts in East Delhi, another region of Northern India, have launched widespread campaigns of insecticide spraying, known as ‘fogging’, while other districts continue with inaction as the situation grows progressively worse. Close monitoring and surveillance of the situation is critical to mitigate the outbreak and prevent further spread to neighbouring regions, and an urgent strategic response is required by the government to contain the dengue outbreak, especially in the context of the Covid-19 pandemic.