An Iowa State professor is using chickens across the state of Iowa to detect levels of the encephalitis virus in mosquitoes.

“The goal is to monitor the problem and tell city and country health departments,” said Wayne Rowley, coordinator of the Statewide Mosquito Encephalitis Virus Surveillance Program.

The dangerous virus cycles between infesting birds and mosquitoes, said Rowley, professor of entomology. Humans are especially at risk when the mosquito population becomes large.

The program to detect the virus, active since 1974, consists of three components, he said.

The first component monitors the mosquito population on a daily basis.

“This tells us when the population has reached a level when encephalitis becomes dangerous,” he said.

The second component is maintaining flocks of 10 sentinel chickens in specially constructed cages, Rowley said. While the chickens are in their cages, researchers test their blood weekly for the virus.

Chickens are especially helpful in looking for encephalitis because of the unique connection between chickens and humans, Rowley said.

“Studies in other cities have shown that the encephalitis virus appears in humans 10 days to two weeks after the virus shows up in chickens,” he said.

The third component is to test mosquitoes for the virus. This is not as effective as the chicken test, though, Rowley said.

If at any stage of the program danger signs do appear, Rowley said researchers contact local media outlets and the appropriate health department.

“A very big part of this is public awareness,” he said.

There have been years when the mosquito population was large enough to pose a danger for people, Rowley said. He noted that the floods of 1993 led to an unusually high mosquito population that summer, which posed a great risk of encephalitis infection to humans.

“Typically, there are six to 15 cases of encephalitis that are laboratory confirmed each year,” he said.

Rowley said encephalitis infections in humans cause symptoms such as high fever and severe headaches and can eventually lead to a coma.

ISU students, the University of Iowa Hygienic Laboratory and various health departments across the state also are working with Rowley on the project.