During a call with U.S. doctors this month, one CDC official noted that there is a seasonality to bird flu: Cases peak in the fall and early winter, possibly due to the migration patterns of wild birds that are primary spreaders of the virus.

CSU researchers work to determine how the virus is spreading Last spring, when the U.S. Department of Agriculture announced that an outbreak of highly pathogenic avian influenza, commonly referred to as bird flu,

Federal officials tracking bird flu have found the virus on poultry farms, but experts say the outbreaks are not currently a concern for the general public.