Aug 6, 2012 (CIDRAP News) – Indiana and Ohio reported a total of 14 more cases of variant swine-origin H3N2 influenza (H3N2v) today and over the weekend, raising the apparent US total in recent weeks to 30 and continuing a string of cases related to agricultural fairs.
In a press release issued late Friday (Aug 3), the Indiana State Department of Health (ISDH) reported six new cases, all of them involving contact with pigs. And today Ken Severson, an ISDH spokesman, told CIDRAP News that three more cases were confirmed.
The Ohio Department of Health (ODH), in a statement today, said its count of recent cases has increased to 15, compared with 10 cited by the Centers for Disease Control and Prevention (CDC) on Aug 3. Fourteen of the 15 cases were in Butler County and were linked to swine exposure at the county fair there, and one case, in Clark County, was tied to swine exposure at the Ohio State Fair, the statement said.
On Aug 3 the US Centers for Disease Control and Prevention (CDC), noting the recent spate of cases, advised the public to take steps to avoid catching the virus from pigs. The agency said people who have an increased risk for flu complications, such as the elderly, small children, and those with chronic diseases, should consider avoiding pigs and swine barns this summer.
CDC officials put the case count as of Aug 3 at 16 in the previous 3 weeks and 29 in the past year. The latest Indiana and Ohio cases boost the apparent numbers to 30 in recent weeks and 43 in the past year. Besides the Indiana and Ohio cases, the recent illnesses include one in Hawaii.
The ISDH's Aug 3 statement said state officials had confirmed six more "variant influenza A" cases, bringing the recent total at that point to 11. The cases were in Tipton, Jennings, and LaPorte counties, and all the patients had had contact with pigs, the statement said.
"We haven’t seen any transmission from person to person at this point," State Health Commissioner Gregory Larkin, MD, said in the ISDH release. "All of the confirmed cases have had direct contact with swine."
LaPorte County, in northwestern Indiana, is the site of four previous cases, which were reported Jul 25 and linked to the LaPorte County Fair. Jennings County is in the southeastern part of the state, just east of Jackson County, where one H3N2v case was reported last week. Tipton County is in central Indiana, north of Indianapolis.
Severson, in reporting three more confirmed cases in Indiana today, provided no further details.
Today's ODH statement said the latest Ohio patients were between 3 and 36 years old and none of them were hospitalized.
The H3N2v virus contains the M, or matrix, gene from the 2009 H1N1 virus, which, according to the CDC, may make it easier for the strain to spread from pigs to humans and from human to human. No human-to-human transmission has been reported this summer, but three cases last fall and winter might have involved such transmission, the CDC said last week.
Most of the recent cases have been in children, some of whom were swine exhibitors at fairs. Children are believed to have little immunity to the novel virus. The illnesses have been described as similar to seasonal flu.
Both the ISDH and ODH urged people to take precautions when visiting county fairs, including washing hands before and after exposure to animals and avoiding eating or drinking in animal areas. Flu viruses are not spread by eating properly prepared pork products, officials say.
Aug 6 Ohio press release
Aug 3 Indiana press release
Aug 3 CIDRAP News story on H3N2v cases