Targeting mosquitoes residing in cattle sheds in countries like India can help in achieving WHO’s goal of eliminating malaria globally by 2030.
The study shows that mosquitoes transmitting malaria often live on cattle sheds built next to or even share a wall with human dwellings. However, control measures are restricted to houses only.
“We found that in an area of India that has a high burden of malaria, most of the mosquitoes that are known to transmit malaria, rest in cattle sheds and feed on both cows and humans,” said Professor Matthew Thomas, from Pennsylvania State University, US.
The study emphasized that mosquito-control efforts urgently need to take into account the relationship between mosquitoes and cattle.
“Understanding the dynamics between humans, cattle and mosquitoes could have major implications for malaria control policy and practice, not only in India but in other areas where transmission is sustained by zoophilic vectors,” added Thomas.
During the study, the team collected a total of 1,774 Anopheles culicifacies and 169 Anopheles fluviatilis mosquito species. These were collected from six villages in Odisha, which has the highest number of malaria cases in India.
These species are the major vectors of malaria on the Indian subcontinent. Researchers found that both species were denser in cattle sheds than in human dwellings, and were feeding on both humans and cattle.
The researchers built a computer model simulating the life of an adult mosquito. It showed that conventional control tools such as insecticide-treated bed nets and indoor insecticide sprays are less effective when mosquitoes exhibit zoophilic behaviour- that is they are attracted to non-human animals.
“However, broadening coverage of non-repellent insecticide sprays to include cattle sheds could help reduce transmission dramatically,” said Thomas.
“The model revealed that directing even modest amounts of effort to specifically increase cattle-based mosquito mortality, associated with zoophilic behaviour can shift the balance towards elimination,” stated the researchers.
Findings of the study have been published in the journal Scientific Reports.
