In an April 17 statement the Michigan Department of Agriculture and Rural Development (MDARD) reported that no new equine herpesvirus-1 (EHV-1) cases have been confirmed since April 3.

A total of four horses have tested positive for the virus since the outbreak began in late March: One Livingston County horse was euthanized, while another Livingston County horse and two Saginaw County horses are recovering at quarantined premises.

The MDARD statement noted that, "in an effort to assist individual horse owners whose horses are currently housed at the quarantined facilities, the (department) allowed three horses quarantined at the … Saginaw County premises to move to isolated locations, one each to Midland, St. Clair, and Genesee counties" last week. The MDARD said the horses that moved have not tested positive for EHV-1, but might have been exposed to EHV-1 positive horses.

"An isolated location has no other horses on the premises or within a quarter of a mile of the premises," the statement indicated. "The three isolated locations are also under quarantine. The reason for allowing horses to move from one premises to another while remaining under quarantine, is that horses continue to have fevers at the Saginaw facility, which restarts the 28-day count for horses that have no fevers or symptoms suggestive of EHV-1. Moving a horse to an isolated location allows that horse to be potentially removed from quarantine sooner than if it had stayed at the original farm