Monell study finds avian flu infection changes fecal odor in birds

New research conducted by the Monell Chemical Senses Center and the U.S. Department of Agriculture found that mallards that contracted the avian influenza experienced a change in their natural fecal odor.

The study was published in the PLOS ONE journal and concluded that the change to the fecal odor may give researchers a new, and potentially easier, way to analyze AIV in birds.

"The fact that a distinctive fecal odor is emitted from infected ducks suggests that avian influenza infection in mallards may be 'advertised' to other members of the population," Bruce Kimball, a research chemist with the USDA National Wildlife Research Center at Monell, said. "Whether this chemical communication benefits non-infected birds by warning them to stay away from sick ducks or if it benefits the pathogen by increasing the attractiveness of the infected individual to other birds, is unknown."

Researchers conducted the study using laboratory mice that were trained to detect the change in odor. The scientists also developed a chemical analysis of the change, which was found to be acetoin and 1-octen-2-ol.

"Avian influenzas are typically asymptomatic in ducks and waterfowl," Gary Beauchamp, a behavior biologist at Monell and study author, said. "Infection in these species can only be diagnosed by directly detecting the virus, requiring capture of birds and collection of swab samples. Our results suggest that rapid and simple detection of influenzas in waterfowl populations may be possible through exploiting this odor change phenomenon."

The phenomenon is not solely present in birds; humans also exhibit a change in chemical compounds when gastrointestinal diseases are present. Researchers will continue to study the potential for scent-based disease detection with other diseases and any related changed in animal behavior.