Mosquitoes may be small but these tiny insects can be deadly as they transmit pathogens that can cause serious and potentially fatal illnesses such as malaria, dengue and Zika.
It appears, however, that mosquitoes have a weakness that can be used in the fight against mosquito-borne diseases particularly malaria, which according to the World Health Organization killed more than 430,000 in 2015.
Findings of a new study have found that these disease carriers are afraid of chickens and this knowledge can be used to reduce incidences of mosquito-borne diseases.
Chemical ecologist Rickard Ignell, from the Swedish University of Agricultural Sciences, and colleagues looked at the behavior of the Anopheles arabiensis mosquitoes in western Ethiopia, where people usually share living quarters with their livestock.
The researchers found that while mosquitoes have strong preference for human blood over those of animals, these insects randomly feed on sheep, goats and cattle outdoors. They also noticed that the malaria-carrying species An. arabiensis avoided chicken both indoors and outdoors regardless if there are many chickens around.
An earlier research already suggested that this particular species of mosquito avoids birds. The new study strengthened the idea that poultry can repel mosquitoes. The researchers theorized that they are averted by the smell of fowl.
To test this theory, the researchers collected feather, hair and wool samples from chickens, sheep, cows, goats and people and isolated the chemicals that made up the scents. Volunteers, who laid in bedrooms where a device emitted synthetic versions of the chemicals, then acted as mosquito baits protected by bed netting.
The researchers found that when the odor smelled like those of chickens, there were up to 95 percent reduction in mosquito counts.
The researchers also conducted an experiment that involved placing a caged live chicken in the bedroom ceiling. They found that the presence of the chicken in the bedroom has resulted in about 80 percent reduction in mosquito counts.
The findings could pave way for the development of mosquito repellents that, in combination with other mosquito-repelling tools such as bed nets, can help protect people from mosquito-borne diseases.
"Non-host volatiles repel host-seeking An. arabiensis and thus play a significant role in host discrimination," the researchers wrote in their study, which was published in Malaria Journal on July 21.
"As such, this study demonstrates that non-host volatiles can provide protection to humans at risk of mosquito-vectored diseases in combination with established control programmes."
