According to a circular mailed by the USAPEEC, authorities in Mexico have lifted a ban on states reporting outbreaks of highly pathogenic avian influenza in noncommercial and backyard flocks. The nation has retained statewide bans on Indiana, Kentucky and Delaware and presumably will impose restrictions on IA, Missouri and states subsequently reporting cases of H5N1 avian influenza in commercial flocks.
Most nations trading with the U.S. have adopted the World Organization for Animal Health (OIE) principle of regionalization. Banning an entire state when only a single county is involved is not based on the epidemiology of avian influenza. An outbreak in a small commercial unit in East Texas should not affect the ability of a producer 600 miles distant in far West Texas from exporting. In some situations during the present series of outbreaks an affected county is adjacent to a second unaffected county in an adjoining state. Banning the entire state with 100 counties as a precautionary measure while ignoring an adjacent neighboring county in an unaffected state is illogical. Banning export or movement through an affected county and possibly contiguous counties could be justified but applying a blanket ban on an entire state is inconsistent with current international regulatory approaches. Applying regionalization, an outbreak in Newcastle County, Delaware, close to the point of intersection with the states of Pennsylvania and Maryland, could require suspension of exports not from the entire state of Delaware but restrictions could be imposed on contiguous counties in adjoining states if located within a control zone, until freedom from infection is demonstrated through surveillance.