Avian influenza infection in ducks results in a distinct fecal odor, a finding that someday might lead to a surveillance tool to track the disease, which is often asymptomatic in animals but can have serious human health consequences.
The discovery came from experiments on mallards by researchers from the Monell Chemical Senses Center and the US Department of Agriculture, who published their findings yesterday in PLoS One.
The team used chemical and behavioral methods to detect the odor changes in infected birds. Chemical analysis found that chemical compounds linked to infection are acetoin and 1-octen-3-ol, which have also been identified as possible markers for gastrointestinal diseases in humans. Researchers also trained lab mice to tell the difference between the feces of infected and uninfected birds, which also indicates a change in odor.
Bruce Kimball, PhD, a study coauthor and USDA research chemist working at Monell, said in a press release that the distinctive odor change might "advertise" avian flu infection to other birds, warning them to stay away from sick ducks. However, he noted that the odor might benefit the pathogen by attracting other ducks.
The researchers said they will conduct further studies to assess if the odor changes can be used for surveillance, if the change is specific to avian flu or is a more generalized response to infection, and how such odors might influence social behavior in wildlife populations.