A summer influenza outbreak at a cancer facility in Little Rock, Ark., sparked concern about the possibility of an unusual strain such as swine-origin variant H3N2 (H3N2v), but the virus turned out to be a seasonal strain of H3N2, according to a state health official.
Thirty-three cases have been reported in the outbreak at the University of Arkansas for Medical Sciences Myeloma Institute, Dirk Haselow, MD, PhD, the Arkansas state epidemiologist, told CIDRAP News.
Given the timing, the outbreak raised concern about the chance of an unusual resistant strain or of H3N2v, among other possibilities, he said.
"We're happy to report that it's not a variant flu. It seems to be a garden-variety seasonal flu," Haselow said. "Tests at CDC verify that it doesn't come from other animals."
More than 300 cases of H3N2v were reported in the United States last summer, the vast majority of them in children who had contact with pigs at county and state fairs. So far this summer, only a few cases have been reported.
Haselow said the first case in the outbreak was reported Jul 30. Of the 33 people affected, 30 have been patients at the institute, 1 is a staff member, and 2 are family members of other case-patients.
About a third of those affected were temporarily hospitalized, but there have been no deaths, Haselow said, noting that patients at the institute all have underlying conditions. "This strain doesn't appear to be more virulent than any other flu," he added.
The origin of the outbreak is unclear, but the likeliest possibility is that the virus was brought in by a patient from a country where seasonal flu is circulating, he said. The Myeloma Institute draws patients from all over the world, and there currently are several who come from places that have seasonal flu outbreaks.
"We really do have high suspicion that it was imported from one of those patients," he said. "We've checked with other hospitals and infection control practitioners, and nowhere else are we seeing a flu outbreak, so it doesn't appear to be locally acquired."
A report yesterday from Little Rock television station KARK 4 said the patients were being treated with oseltamivir and that staff members in the ward were receiving preventive treatment.
Because it's not flu season, the health department is sending an alert about the outbreak to all Arkansas physicians, the story noted.
Aug 6 KARK 4 story