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Photo by Geri Glastra
Research published in Malaria Journal indicates that malaria-transmitting mosquitoes use their sense of smell to avoid feeding on chickens.
Investigators therefore believe that odors emitted by chickens and other animals could provide protection for humans at risk of mosquito-transmitted diseases.
The study showed that Anopheles arabiensis, one of the predominant species of mosquitoes transmitting malaria in sub-Saharan Africa, avoids chickens when looking for hosts to feed on.
And the mosquitoes can distinguish chickens from other animals using their sense of smell.
“We were surprised to find that malaria mosquitoes are repelled by the odors emitted by chickens,” said study author Rickard Ignell, PhD, of the Swedish University of Agricultural Sciences in Alnarp, Sweden.
“This study shows, for the first time, that malaria mosquitoes actively avoid feeding on certain animal species and that this behavior is regulated through odor cues.”
To find out which species the mosquitoes prefer, Dr Ignell and his colleagues collected data on the population of human and domestic animals in 3 Ethiopian villages. People living in these villages share their living quarters with their livestock.
The investigators also collected blood-fed mosquitoes to test for the source of the blood the mosquitoes had consumed.
The team found that An arabiensis strongly prefers human over animal blood when seeking hosts indoors and randomly feeds on cattle, goats, and sheep when outdoors. However, the mosquitoes avoid chickens in both settings, despite their relatively high abundance.
Since mosquitoes select and discriminate between their hosts mainly based on their sense of smell, the investigators collected hair, wool, and feathers from potential host and non-host species to analyze the odor compounds present in them.
Identifying certain compounds that were only present in chicken feathers, the team used these and other compounds obtained from all species to test their ability to repel mosquitoes from mosquito traps.
The traps were set up in 11 thatched houses in one of the villages for a total of 11 days. In each of the houses, a single volunteer between ages 27 and 36 slept under an untreated bed net.
The investigators found that significantly fewer mosquitoes were caught in traps baited with chicken compounds than in control traps. Suspending a living chicken in a cage next to a trap had a similar repellent effect.
Because it feeds indoors and outdoors on various host species, An arabiensis is difficult to control with existing methods, previous research has shown. The results of the current study suggest that, in combination with established control methods, the odors emitted by chickens and other non-host species could prove useful in controlling An arabiensis.
“People in sub-Saharan Africa have suffered considerably under the burden of malaria over an extended period of time, and mosquitoes are becoming increasingly physiologically resistant to pesticides, while also changing their feeding habits, for example, by moving from indoors to outdoors,” Dr Ignell said.
“For this reason, there is a need to develop novel control methods. In our study, we have been able to identify a number of natural odor compounds which could repel host-seeking malaria mosquitoes and prevent them from getting in contact with people.” 
Photo by Geri Glastra
Research published in Malaria Journal indicates that malaria-transmitting mosquitoes use their sense of smell to avoid feeding on chickens.
Investigators therefore believe that odors emitted by chickens and other animals could provide protection for humans at risk of mosquito-transmitted diseases.
The study showed that Anopheles arabiensis, one of the predominant species of mosquitoes transmitting malaria in sub-Saharan Africa, avoids chickens when looking for hosts to feed on.
And the mosquitoes can distinguish chickens from other animals using their sense of smell.
“We were surprised to find that malaria mosquitoes are repelled by the odors emitted by chickens,” said study author Rickard Ignell, PhD, of the Swedish University of Agricultural Sciences in Alnarp, Sweden.
“This study shows, for the first time, that malaria mosquitoes actively avoid feeding on certain animal species and that this behavior is regulated through odor cues.”
To find out which species the mosquitoes prefer, Dr Ignell and his colleagues collected data on the population of human and domestic animals in 3 Ethiopian villages. People living in these villages share their living quarters with their livestock.
The investigators also collected blood-fed mosquitoes to test for the source of the blood the mosquitoes had consumed.
The team found that An arabiensis strongly prefers human over animal blood when seeking hosts indoors and randomly feeds on cattle, goats, and sheep when outdoors. However, the mosquitoes avoid chickens in both settings, despite their relatively high abundance.
Since mosquitoes select and discriminate between their hosts mainly based on their sense of smell, the investigators collected hair, wool, and feathers from potential host and non-host species to analyze the odor compounds present in them.
Identifying certain compounds that were only present in chicken feathers, the team used these and other compounds obtained from all species to test their ability to repel mosquitoes from mosquito traps.
The traps were set up in 11 thatched houses in one of the villages for a total of 11 days. In each of the houses, a single volunteer between ages 27 and 36 slept under an untreated bed net.
The investigators found that significantly fewer mosquitoes were caught in traps baited with chicken compounds than in control traps. Suspending a living chicken in a cage next to a trap had a similar repellent effect.
Because it feeds indoors and outdoors on various host species, An arabiensis is difficult to control with existing methods, previous research has shown. The results of the current study suggest that, in combination with established control methods, the odors emitted by chickens and other non-host species could prove useful in controlling An arabiensis.
“People in sub-Saharan Africa have suffered considerably under the burden of malaria over an extended period of time, and mosquitoes are becoming increasingly physiologically resistant to pesticides, while also changing their feeding habits, for example, by moving from indoors to outdoors,” Dr Ignell said.
“For this reason, there is a need to develop novel control methods. In our study, we have been able to identify a number of natural odor compounds which could repel host-seeking malaria mosquitoes and prevent them from getting in contact with people.”
Photo by Geri Glastra
Research published in Malaria Journal indicates that malaria-transmitting mosquitoes use their sense of smell to avoid feeding on chickens.
Investigators therefore believe that odors emitted by chickens and other animals could provide protection for humans at risk of mosquito-transmitted diseases.
The study showed that Anopheles arabiensis, one of the predominant species of mosquitoes transmitting malaria in sub-Saharan Africa, avoids chickens when looking for hosts to feed on.
And the mosquitoes can distinguish chickens from other animals using their sense of smell.
“We were surprised to find that malaria mosquitoes are repelled by the odors emitted by chickens,” said study author Rickard Ignell, PhD, of the Swedish University of Agricultural Sciences in Alnarp, Sweden.
“This study shows, for the first time, that malaria mosquitoes actively avoid feeding on certain animal species and that this behavior is regulated through odor cues.”
To find out which species the mosquitoes prefer, Dr Ignell and his colleagues collected data on the population of human and domestic animals in 3 Ethiopian villages. People living in these villages share their living quarters with their livestock.
The investigators also collected blood-fed mosquitoes to test for the source of the blood the mosquitoes had consumed.
The team found that An arabiensis strongly prefers human over animal blood when seeking hosts indoors and randomly feeds on cattle, goats, and sheep when outdoors. However, the mosquitoes avoid chickens in both settings, despite their relatively high abundance.
Since mosquitoes select and discriminate between their hosts mainly based on their sense of smell, the investigators collected hair, wool, and feathers from potential host and non-host species to analyze the odor compounds present in them.
Identifying certain compounds that were only present in chicken feathers, the team used these and other compounds obtained from all species to test their ability to repel mosquitoes from mosquito traps.
The traps were set up in 11 thatched houses in one of the villages for a total of 11 days. In each of the houses, a single volunteer between ages 27 and 36 slept under an untreated bed net.
The investigators found that significantly fewer mosquitoes were caught in traps baited with chicken compounds than in control traps. Suspending a living chicken in a cage next to a trap had a similar repellent effect.
Because it feeds indoors and outdoors on various host species, An arabiensis is difficult to control with existing methods, previous research has shown. The results of the current study suggest that, in combination with established control methods, the odors emitted by chickens and other non-host species could prove useful in controlling An arabiensis.
“People in sub-Saharan Africa have suffered considerably under the burden of malaria over an extended period of time, and mosquitoes are becoming increasingly physiologically resistant to pesticides, while also changing their feeding habits, for example, by moving from indoors to outdoors,” Dr Ignell said.
“For this reason, there is a need to develop novel control methods. In our study, we have been able to identify a number of natural odor compounds which could repel host-seeking malaria mosquitoes and prevent them from getting in contact with people.”