In Maryland, 20 cases and one adult death have been reported this year. D.C. health officials confirmed the city’s first fatality Wednesday, a Northeast Washington resident. A Southeast resident is hospitalized. No additional details were available. Virginia has five confirmed cases and no fatalities.
Texas continues to be the state hit hardest, accounting for about half of all reported U.S. cases this year. Aerial spraying of insecticide in some areas has reduced the population of mosquitoes that carry the virus, officials there said. But the number of human cases is expected to rise through October because of the lag time between infection and reporting of the illness.
As of Tuesday, a total of 1,993 cases nationwide, including 87 deaths, had been reported to the U.S. Centers for Disease Control and Prevention, a 25 percent increase in the number of cases and a 32 percent increase in deaths from the previous week.
Asked about recent disease outbreaks, including the hantavirus outbreak traced to Yosemite National Park, Lyle Petersen, director of the CDC division of vector-borne infectious diseases, said pathogens are spreading faster because people and goods are moving around the planet at record rates. “The world is a smaller place right now,” he said.
U.S. health officials have notified 39 countries that their citizens might be at risk from the rodent-borne hantavirus after traveling recently to Yosemite. Six hantavirus cases, two of which were fatal, have been linked to the park. The CDC said that as many as 10,000 people were at risk after staying in Yosemite’s “signature tent cabins” between June 10 and Aug. 24.
For Texas, 2012 is “the worst year ever for West Nile virus,” the state health commissioner, David Lakey, told reporters during a conference call. The state had 1,013 confirmed cases and 40 deaths.
More than 70 percent of the cases this year have been reported in six states: Texas, South Dakota, Mississippi, Oklahoma, Louisiana and Michigan.
Most people who become infected have no symptoms. In Texas, 89 people found out they had been infected during routine screening for blood donation, Lakey said. A spokeswoman for the American Red Cross said volunteer blood donors are routinely screened for West Nile virus. As of Wednesday, more than 200 would-be donors in 28 states had tested positive this year for West Nile, and the numbers are expected to rise, Red Cross spokeswoman Karen Stecher said. Blood infected with the virus is destroyed or used for research, she said.