Novel H3N2 swine flu viruses infected 2 children, CDC says

Robert Roos News Editor

Sep 2, 2011 (CIDRAP News) – In separate instances, influenza A/H3N2 viruses circulating in swine picked up a gene from the pandemic 2009 H1N1 virus and recently infected two young children, one in Indiana and one in Pennsylvania, the Centers for Disease Control and Prevention (CDC) reported today.

Both of the children recovered, though one was briefly hospitalized, and there is no sign that the viruses spread from the children to others, but any evidence of ongoing transmission would require a rapid response, the CDC said.

The agency also said one of the children had no direct contact with pigs, which suggests he caught it from another person. Both children are under age 5.

The two viruses are similar to eight other swine-origin H3N2 viruses found in humans in the past 2 years, but they are unique in that they contain the matrix (M) gene from the 2009 H1N1 virus, the CDC reported in an early online posting in Morbidity and Mortality Weekly Report (MMWR). The two viruses are similar but not identical.

"I don't think these [viruses] have pandemic potential; it looks like both of these are sort of dead-end transmissions," Dr. Lyn Finelli, chief of the surveillance and outbreak response team in the CDC's influenza division, told CIDRAP News.

But she also commented, "One of the reasons we publish this data is that reassortment happens in swine viruses and in humans, so we always want to have surveillance in place so we can detect the next emerging reassortant. Viruses like these do have pandemic potential."

Though no further cases have been found, the report says, "If additional chains of transmission are identified rapid intervention is warranted [to] try to prevent further spread of the virus."

Case details
The first case involved an Indiana boy who got sick with a fever, cough, shortness of breath, diarrhea, and..

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