In Texas, the state hit hardest by the West Nile epidemic, UTMB virologist Alan Barrett said samples of the virus taken from mosquitoes and birds in the Houston area show signs of genetic changes. “This year’s virus looks more like the virus from 2002 and 2003” than the virus seen more recently, said Barrett. Given that the Houston-Galveston area is a major flyway for birds, Barrett speculated that a different virus arrived in the area this year. But it is too early to say whether this possible new strain is more virulent than those seen in years past, Barrett said. It will also take a while to study the genetics of viruses from other parts of the country. His laboratory, one of the few studying West Nile genetics, is backlogged with samples. “We’re overwhelmed,” he said.