CDC issues warning about swine flu variant

The Centers for Disease Control and Prevention (CDC) are telling children younger than 5, adults over 65 and pregnant women to avoid close contact with pigs at agricultural fairs after four cases of swine influenza infecting people were confirmed in Michigan and Ohio.

The CDC warning says the infections were caused by the H3N2v virus. The Associated Press reported two people who exhibited pigs at the Muskegon County Fair in Michigan between July 25 and 30 were infected. An Iowa lab confirmed a pig at the fair had the virus. In Ohio, two children were infected at the Clark County Fair after “direct contact with the pigs there,” according to the Dayton Daily News.

In the Ohio cases, neither child needed to hospitalized, and both of those infected in Michigan recovered. Swine flus don’t normally spread to humans, and when they do, the cases are usually mild. The CDC is still advising people most at-risk for flu complications to stay away from swine barns at fairs.

“Agricultural fairs take place across the United States every year, primarily during the summer months and into early fall,” the agency said. “Many fairs have swine exhibitions, where pigs from different places come in close contact with each other and with people. These venues may magnify the risk of spread of influenza viruses between pigs and people. The number of variant virus infections reported in humans has varied from season to season.”

The four confirmed cases of humans contracting H3N2v are slightly above the three infections detected in each of the prior two years, and far below the wider spread infections of 2012, when 309 human infections were detected, 16 people were hospitalized and one person died. Those larger outbreaks are why the CDC is watching these cases.

“Human infections with a non-human influenza virus should be fully investigated to be sure that such viruses are not spreading in humans in an efficient and ongoing way, and to limit further exposure of humans to infected animals if infected animals are identified,” the agency said. “At this time, the epidemiology of the human infections reported this week seems consistent with what has been in the past. None of the most recent infections were hospitalized and there were no deaths.”

The CDC notes the seasonal flu vaccine doesn’t protect against H3N2v, though antiviral drugs, such as oseltamivir, peramivir and zanamivir, can be used to treat variant virus infection.