"Since last summer, the scientists have been working with Animal and Plant Health Inspection Service at the U.S. Department of Agriculture to look for signs of

"Since last summer, the scientists have been working with Animal and Plant Health Inspection Service at the U.S. Department of Agriculture to look for signs of the virus in blood and fecal samples from local rats. So far, they’ve come up empty." Leaving the unpleasant possibility that cats and dogs, the only other species whose DNA is found in quantity in the NYC sewage, are the carriers.