# 6530
File this under - `Once you start looking, no telling what you’ll find’.
Enhanced surveillance for H3N2v flu cases associated with contact with pigs by Minnesota’s Department of Health has turned up 1 confirmed, and 2 probable human cases of H1N2v influenza.
The H1N2 virus is one of three flu strains that commonly circulate in swine (H1N1, H3N2, & H1N2).
H1N2 is assumed to be a reassortment between the H1N1 and H3N2 virus. It has on rare occasions been detected in humans.
Credit CDC
Minnesota reported a human infection with A/H1N2 in December of 2011, and it was said to be similar to an H1N1 virus (A/New Caledonia /20/99-like) that circulated as recently as 2007.
Michigan reported an H1N2 human infection in 2007.
As has been pointed out in this blog before, we honestly don’t know how often these novel swine (or avian)origin flu viruses jump to humans. Given the limits of testing and surveillance, it is probably more common than the numbers suggest.
Heightened surveillance around the country for the H3N2v virus may very well tell us a good deal about other variant viruses that we know can occasionally show up in the human population.
Here is the Press release from the MDH.
News Release
August 31, 2012
Three human cases of influenza linked to swine exposure at State Fair
Strain is different from the one that prompted current surveillance and prevention efforts
Three people are believed to have developed a strain of influenza known as variant H1N2 (H1N2v) after exhibiting pigs or spending time in the swine barn at the Minnesota State Fair.
One of the three cases has been confirmed by CDC. Test results for the other two are pending.
The H1N2v strain is different from the H3N2v strain that has prompted stepped up surveillance and prevention efforts nationwide, after causing 289 reported cases of illness and one death since the beginning of the year.
Officials at the Minnesota Department of Health (MDH) say they are not currently aware of any additional human influenza cases caused by H1N2v, and they do not anticipate changing their current public health recommendations regarding human exposure to swine.
They emphasized, however, that they will continue to assess the situation and conduct aggressive surveillance for additional influenza cases.
Current recommendations include asking individuals at high risk for severe influenza to avoid swine contact at exhibitions, fairs, live markets and other venues, including the swine barn at the State Fair. High risk individuals include children under five years of age, pregnant women, people 65 years of age or older and those with chronic medical conditions.
"For the past two weeks, we have been looking very hard for cases of influenza in people who have been exposed to swine," said Richard Danila, Deputy State Epidemiologist. "We have also worked closely with our veterinary colleagues to remain informed about potential infections in swine at the Fair. It is because of this careful surveillance that these cases have come to our attention.
"Right now, we don’t have any basis for changing our recommendations to the public," Danila said.
The illness has been confirmed in a teenage girl who was exhibiting pigs at the fair and became ill on Aug. 26. The other two cases occurred in an elementary-school-aged boy who became ill on Aug. 27 after spending all day in the swine barn on Aug. 24, and a woman in her late seventies who became ill on Aug. 26 after spending a prolonged period of time in the swine barn and at the swine show in the Exhibit Hall on Aug 24.
Both the boy and the older woman had underlying health conditions, and were treated with antiviral drugs. The woman was hospitalized, but has now been released. All three patients have recovered or are recovering.
The teenager was tested for influenza after she reported illness to nursing staff at the Fair. The other cases were reported to MDH by health care providers. Health care providers have been asked to report cases of influenza-like illness in people who report that they have had contact with swine. Swine exhibitors have been asked to report it if they experience symptoms of influenza.
Fair officials have also been monitoring swine for possible symptoms of illness, so they can be tested. Two pigs at the swine exhibit were found to be infected with the same H1N2 virus earlier this week, and were both isolated from contact with other pigs. Infection with H1N2 is not considered unusual in pigs.
-MDH-
For more on the H1N2 virus, you may wish to revisit:
Hong Kong Swine Influenza Surveillance
CDC: Variant Influenza Strains
CDC Confirms 2 More Novel Flu Infections
If You’ve Seen One Triple Reassortant Swine Flu Virus . . .
