December 28, 2011 — The number of reported cases of a novel swine influenza virus has risen to 12 since July, encompassing 5 states, according to the US Centers for Disease Control and Prevention (CDC). The virus includes a gene from the human pandemic strain and affects mostly children.

The agency is taking the influenza newcomer seriously, urging public health departments, hospitals, and clinicians engaged in influenza surveillance to consider the possibility of the virus in patients presenting with influenza-like illness (ILI).

The infections in question involve a variant of the A(H3N2) virus that circulates among pigs. It contains a gene from the pandemic 2009 influenza A(H1N1) virus that codes for matrix proteins found in the viral shell.

The novel virus is worrisome enough that the CDC, the World Health Organization, and the World Organisation for Animal Health have dubbed it A(H3N2)v. The "v," which stands for "variant," distinguishes the novel virus from the seasonal A(H3N2) virus. The 2011-2012 seasonal influenza vaccine is designed to protect against this strain, the 2009 pandemic strain, and an influenza B strain.

In 3 of the 5 states where the A(H3N2)v virus has surfaced — Indiana, Pennsylvania, and Maine — patients became infected after direct or indirect contact with pigs. In Iowa and West Virginia, the other 2 states, the evidence suggests that the virus spread from human to human on a limited basis.

The CDC has not found evidence of sustained human-to-human transmission of the virus, but "all influenza viruses have the capacity to change, and it's possible this virus may become widespread," the agency states on its Web site.

One seeming bit of good news is that, so far, the A(H3N2)v virus causes illnesses that are generally no worse than those triggered by the seasonal influenza virus. Three of the 12 patients were hospitalized, but they and all the others recovered.

However, there is a bad-news chaser: The seasonal influenza vaccine for 2011-2012 is unlikely to protect people from the A(H3N2)v virus, the CDC reports. In addition, limited serologic studies indicate that young children have little preexisting immunity, although older children and adults may have limited immunity.

Read more here: http://www.medscape.com/viewarticle/756148

Of course, what else is new? I don't have time to delve into this right now, but I have a question - if this is a novel variant, how were the scientists so foresighted to include it in this year's vaccine? If I get a chance I'll do more research on this, but maybe I missed something in the previous article that somebody could point out to me. TIA

http://www.cdc.gov/flu/about/qa/vaccine-selection.htm

Good catch and great question, Ruts! I think the Medscape article is misleading because they fail to point out the above information. The 2011-2012 flu vaccine is targeted toward the H3N2 virus - not the variant.

I think...

On further reading, (Thanks Blue) the article is even more misleading, or rather either confused or the author doesn't know what s/he is talking about. here are the inconsistencies:



So the strain labeled "v" is definitely new in 2011, beginning in July.

This sentence indicates that the current year's vaccine supposedly protects against this particular strain that the article is about - the "v" strain, which was only identified in 2011, presumably sometime in the latter part of the year, since the first known incident of the strain was in July.



Now the author reverses the previous statement that this year's vaccine is designed to protect against "this" strain ("this" being the "v" strain) by saying that this year's vaccine is UNLIKELY to protect people from the "v" strain!! Or perhaps this is the truest statement in the article, since all vaccines are UNLIKELY to protect people from viruses. (I won't get on my soapbox right now about the negatives of vaccines.)

New pig flu strain can spread at state fairs, CDC warns

By MIKE STOBBE

ATLANTA — It's the season for state and county fairs, and health officials are reminding fairgoers to be careful around pigs because of a new flu spreading from the animals to people.

Officials say 29 human cases of the new strain of swine flu have been confirmed in the last year, including 12 this week. Ten were linked to the Butler County Fair in southwest Ohio, which ended last weekend.

snip

Read more here: http://tinyurl.com/d4xvaxn

New pig flu spreads to more people, CDC says

By Maggie Fox, NBC News

As many as 145 people have been infected this summer with a new pig flu virus, the U.S. Centers for Disease Control and Prevention said on Thursday, although the disease does not appear to be any more serious than normal seasonal flu. Nine out of 10 of them are children, CDC says.

Most cases appear to be among people who were showing pigs, or people visiting fairs and other places where these pigs are, CDC says. This suggests they are catching the flu directly from infected pigs. So far everyone has gotten better on their own, Dr. Joseph Bresee, from the CDC's influenza division, told reporters on a telephone briefing.

“At this point there is no evidence of sustained, efficient human to human spread,” Bresee said. “This is not a pandemic situation.”

snip

Read more here: http://vitals.nbcnews.com/_news/2012/08/09/13201621-new-pig-flu-spreads-to-more-people-cdc-says?lite