In spite of the hundreds of deaths it has caused in the last few years and the government acknowledging that prevention is the only cure for dengue, India’s response to the disease remains reactive, and not preventive.
According to the National Vector Borne Disease Control Programme (NVBDCP), about 13,000 cases of dengue were reported in 2006. The disease killed nearly 200 people. Delhi topped the list with nearly 28 per cent of the cases followed by Rajasthan and Maharashtra. Yet, prevention remains low.
Other tropical countries like Vietnam, Cuba and Malaysia have launched successful biological battles against Aedes aegypti, commonly known as the tiger mosquito, which spreads the disease in humans. Vietnam successfully used a bug, mesocyclops, that eats mosquito larvae but is harmless to humans. Within a year of launching the programme, Vietnam brought down the incidence of dengue by nearly 77 per cent.
But can India follow Vietnam’s example? “There is no reason why that cannot happen, unless the resources needed to accomplish it are not available due to the sheer magnitude of the problem,” Joseph M. Conlon, technical advisor, American Mosquito Control Association, told HT. Conlon added that current programmes in Kuala Lampur, utilising a bacterial spore called Bti-H14 to attack the mosquito larvae, “have shown promise”. And Cuba effectively used tree frog tadpoles that feed on the larvae.
“We are not using any biological prevention right now because there is not enough specific information available with us on what would work best in which region,” said a senior scientist at the Vector Control Research Centre, Puducherry. “The diversity prevents us from a common prescription for the entire country,” he added.