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Published Date: 2012-08-09 15:24:52
Subject: PRO/AH/EDR> Influenza (67): USA (IN, OH), A(H3N2)v, more cases
Archive Number: 20120809.1236861

INFLUENZA (67): USA (INDIANA, OHIO), A(H3N2)V, MORE CASES
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[1]
Date: Wed 8 Aug 2012
Source: CIDRAP (Center for Infectious Disease Research & Policy) News [edited]
http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/aug0812h3n2v.html

Variant H3N2 cases surge in Indiana, Ohio
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The count of swine-origin variant H3N2 influenza (H3N2v) cases in Indiana soared to 113 today [8 Aug 2012], a jump of about 100, while Ohio reported a total of 30 cases, double the previous number. But the states said they have not found any person-to-person transmission of the virus.

In a news release, the Indiana State Department of Health (ISDH) said the 113 cases are scattered among 18 counties and predicted that more cases would be confirmed this week. Most of the previous cases have been in children who had contact with pigs at county fairs, but today's announcement gave no details about the patients' age range, swine exposure, or severity of illness. The Ohio announcement states, "There are currently 30 cases of H3N2v statewide; all individuals had direct contact with swine at fairs and no human-to-human passage of the virus has been confirmed." The counties and their case numbers are Butler, 16; Clark, 3; Gallia, 4; Greene, 4; and Hamilton, 3.

The Ohio patients range from 6 months to 36 years old, the statement said. It said one patient was hospitalized as a precaution but has since been released. One other H3N2v case was reported recently in Hawaii. With the new Indiana and Ohio cases, the apparent total for the past few weeks has now reached 144. However, Tom Skinner, a spokesman for the US Centers for Disease Control and Prevention (CDC), cautioned that the growing case count in part reflects increased testing and that some of the cases may not ultimately be confirmed.

"The increase in Indiana and soon to be other states is because states are now reporting presumptive positive cases based on testing in their labs and part of this is because of increasing numbers of samples arrived for testing compared with last week," Skinner commented via e-mail. He added that the CDC believes most of the cases are still due to contact with pigs. "However, limited human-to-human transmission with this virus has been observed in the past, and we expect that some human to human spread will be observed in these current outbreaks," he said. The Indiana release said, "Health officials have not determined person-to-person transmission at this time, but continue to investigate the possibility."

Skinner and officials from the 2 states reemphasized the need to take precautions around pigs and when attending fairs. People should wash their hands before and after touching animals and should avoid eating, drinking, or putting anything in the mouth when visiting animal areas, officials said. They also reiterated that the virus is not spread through eating properly prepared pork. The CDC has said that 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. "It's important for folks to remember this is a mild illness with symptoms similar to what we see with seasonal flu," said State Health Commissioner Gregory Larkin, MD, in the Indiana statement today. The CDC has developed a candidate vaccine for the new strain, and clinical trials of versions made by two companies are expected this fall.

Indiana counties that have had H3N2v cases, according to today's announcement, are Bartholomew, Greene, Hamilton, Hendricks, Jackson, Jennings, Johnson, Kosciusko, LaPorte, Lawrence, Monroe, Morgan, Owen, Porter, Scott, Tipton, Washington, and White. A report from Indiana Public Media today said 68 people in Monroe County have contracted the virus. Penny Caudill, administrator of the Monroe County health Department, said the virus does not appear to have spread from person to person, according to the story. The swine barn at the Monroe County Fair was closed last week because of sickness among the pigs.

[Byline: Robert Roos, Lisa Schnirring]

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[2]
Date: 9 Aug 2012
Source: Boston.com (AP) [edited]
http://www.boston.com/lifestyle/health/2012/08/09/cdc-cases-new-swine-flu-strain-from-pigs/0D9SRdONnQgLtCZzFHqK5J/story.html

CDC: 158 cases of new swine flu strain from pigs
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Health officials Thursday reported a five-fold increase of cases of a new strain of swine flu that spreads from pigs to people.

The cumulative case count jumped from 29 a week ago to 158 this week, thanks to a wave of new cases confirmed in Indiana and Ohio, the Centers for Disease Control and Prevention said. Most of the cases have been tied to state and county agricultural fairs, where visitors are put in close contact with infected pigs, said the CDC's Dr. Joseph Bresee.

The recent cases include at least 113 in Indiana, 30 in Ohio, one in Hawaii and one in Illinois, Bresee said.

Most of the infected patients are children -- probably because many were working closely with raising, displaying and visiting pigs at the agricultural fairs, Bresee said.

Also, diagnosis of cases has become quicker in the last week. CDC no longer must confirm a case with its own lab. Now states are using CDC test kits to confirm cases on their own on, speeding the process along. The patients were likely infected a week or two ago.

The CDC has been tracking cases since last summer. A concern: the new strain has a gene from the 2009 pandemic strain that might let it spread more easily than pig viruses normally do.

The good news is the flu does not seem to be unusually dangerous. Almost all of the illnesses have been mild and no one has died. Two of the recent cases were hospitalized, but both recovered and were discharged, added Bresee, the agency's chief of influenza epidemiology.

More good news is that all of the recent cases appear to have spread from pigs to humans, meaning it's not very contagious, at least between people.

But there probably will be more cases in the weeks ahead, and it won't be surprising if at least a few of them involve person-to-person transmission, Bresee said.end of story marker

[byline: Mike Stobbe]

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[Type A influenza viruses, including H3N2 and its variants, commonly infect swine, causing outbreaks among swine herds. Most of the type A influenza viruses that infect swine are genetically very different from human (seasonal) influenza viruses. While these variant swine influenza viruses seldom infect humans, such infections can and do occur. In fact, influenza viruses can spread both from swine to humans and from humans to swine. The A(H3N2)v swine influenza virus strain currently causing human infections at agricultural fairs in some parts of the United States has not so far been detected in pigs in European countries.

Only people in direct contact with infected swine, such as in swine barns and livestock exhibits housing swine at fairs, are likely to be at risk of contracting this H3N2v strain of influenza virus. However transmission of this strain of H3N2v influenza virus is thought to occur in the same way that seasonal flu transmits in people, which is mainly through coughing or sneezing by people who are infected. People also may become infected by touching something with flu viruses on it and then touching their mouth or nose. It's important to note that in most cases, variant flu viruses have not shown the ability to spread easily and sustainably from person to person.

Maps:
Indiana: http://healthmap.org/r/1DmR and http://www.digital-topo-maps.com/county-map/indiana.shtml (counties)
Ohio: http://healthmap.org/r/1BY2 and
http://www.digital-topo-maps.com/county-map/ohio.shtml (counties). - Mod.CP]

[We have learned that the vast majority of human H3N2v infection has been in children. This may reflect immunologic susceptibility due to lack of prior exposure to similar viruses or vaccine antigens, greater exposure of children to swine at agricultural fairs, or a combination of factors. Case numbers will undoubtedly rise as awareness increases and more people are tested. - Mod.LM]

See Also