The Michigan Department of Agriculture and Rural Development has issued an emergency order following the depopulation of Herbruck’s Poultry Ranch in addition to outbreaks of the infection in turkey flocks in western Michigan.  The “HPAI Risk Reduction Response Order” emphasizes biosecurity.  The order is very much a case of shutting the door after the horse has bolted since Herbruck’s Poultry Ranch exercised a high level of biosecurity.  The same cannot be said for the 14 dairy farms that have encountered bovine influenza-H5N1 to date.

With respect to outbreaks on diary farms, control measures will require an understanding of the mode of transmission and current prevalence of infection.  This should be based on a program involving comprehensive industry surveillance. Success will require cooperation among farmers, state and federal agencies and should involve both livestock and workers.  Press reports and public statements by administrators in some states suggest obstruction and failure to cooperate in what must be regarded as an essential epidemiologic investigation.  Fortunately, the current risk to consumers is negligible if milk is pasteurized and meat is adequately cooked. Irrespective of the current low risk to humans, it is essential to subject isolates to molecular assay to detect possible mutations that could favor human infection. Surveillance should encompass poultry flocks, dairy herds and both free-living mammalian and avian species.