Communities need to work closely with health services in the battle against mosquitoes spreading dengue – a serious illness that afflicts around 50 million people each year – as much more than just insecticides are needed to control the disease.
This was observed in a study published in the recent edition of ‘Bulletin of the World Health Organisation’. The study identifies the highest number of mosquito (Aedes Aegypti) larvae in unused and uncovered outdoor containers on private lands in six Asian cities.
It also explored the breeding patterns of the Aedes aegypti (the mosquito specie which transmits dengue) and discovered significant differences in breeding of mosquitoes and dengue transmission between the sites, affected by factors such as household habits, local environmental conditions and the ecology and behaviour of the mosquito.
For the first time, the large-scale multi-country study, supported by a research partnership between the Special Programme for Research and Training in Tropical Diseases (TDR) at the WHO and the International Development Research Centre in Canada, comprehensively combed public and private buildings and open spaces in selected areas in India, Indonesia, Myanmar, Philippines, Sri Lanka and Thailand.
The study identified almost 50,000 containers holding water and found the highest number of mosquito larvae in unused and uncovered outdoor containers on private lands. It established that this mosquito variety prefers to breed in containers filled with rain water. When larvicides were used at the study site in Thailand, the mosquitoes found alternative breeding sites indoors in covered containers filled with tap water.
Large-scale insecticide spraying was found to be ineffective in reducing immature (larval) stages of the mosquito.
“[Aedes aegypti] breed in various water containers in and around households so individuals, families and communities have an equally important role to play in reducing these breeding sites in their own backyards,” states the study. “Communities need to work closely with public health and other services concerned to play a positive role in this battle.”
Dengue is a serious, potentially fatal, illness and infections have increased dramatically in recent decades due to increased urbanisation, travel and trade. No effective drugs or vaccines are available yet so the only solution is to prevent the disease-carrying mosquito from breeding and biting humans.
