A Long Island City warehouse has been transformed into a safe haven for more than 500 cats who may have been exposed to an unusual flu virus. “We came to the decision that it is in the best interest of the cats to move them all to a quarantine facility while we clean the buildings.” She contacted experts at the University of Wisconsin’s Veterinary Diagnostic Lab. They determined the virus was a rare strain of avian flu — the first time it had ever spread to domestic cats.