The State Fair is about to start up here in Minnesota, and the top epidemiologist at the University of Minnesota has very clearly stated that the swine should be excluded this year in order to avoid swine to human transmission of a flu virus that has been showing up in increasing numbers lately. I’ve blogged about this before, and here is an update with new numbers. Also, I’ll address a few questions I’ve heard asked.

How many people have been affected with the new Influenza A (H3N2) Variant Viruses (“H3N2v”)?

The CDC reports that 12 people were known to have been affected in 2011, and 225 in 2012, most of which have been affected in the last several weeks, indicating a sudden outbreak. However, that number is a minimum as more cases are known than reported in that CDC report. We may have one or two cases in Minnesota that have not been included yet.

Who is getting this flu?

There are two categories of people that make up most of those affected: 1) People who work with swine and 2) People who came into contact with swine at county or state fairs or similar venues.

Among those who are getting the flue, more may be children. It is thought that perhaps many adults have a immunity to this variety that children don’t have.

Does the new swine flu pass from human to human?

Yes and no. There are a handful of cases of humans having this flu who probably got it from someone who, in turn, got it from a pig. However, there is not a pattern of sustained human-to-human transmission at this time. However, that can change. The new flu variant has a mutation that is believed to be helpful (to the virus) in human-to-human transmission, and the fact that there are a couple of cases of this shows that is is possible. The reasons that the normal flu season occurs in the Northern Hemisphere during winter may relate to factors that enhance human-to-human transmission, and those factors to not pertain at this time since it is still summer. It is possible that this flu would spread more readily among humans as conditions change. Also, flu viruses change over time to become more or less likely to spread. This flu must be watched carefully.

People are saying that this is a mild flu. Is that true?

No, that is absolutely not true. The flu appears to be an average flu, like any year’s typical seasonal flu, in how icky it is to get it. Rumors that it is a “mild” flu probably come from the fact that it is not a killer flu, like some are that jump boundaries between species. Which may relate to the next question…

Where does this flu come from?

A simple version is that over several years, it started in humans, infected pigs (and went away in humans) and is now re-infecting humans after a period of time of not being able to make that jump. Influenza is like that. This also explains the fact that some adults seem immune to the flu; they had this one (well, one kinda like it anyway) already, or an earlier vaccination is helping.

Should they allow pigs at the Minnesota State Fair?

Personally, I think it is overcautious to disallow pigs. But I think we should be overcautious and disallow them. I agree with Michael Osterholm that this is “an unprecedented situation globally.”

What about taking precautions like washing your hand after petting the pig?

Well, yes, please do wash your hands after petting the pig, but it won’t help much. The flu is probably airborne. Also, officials say they will keep the sick looking pigs sequestered or send them home or something, but there is evidence that pigs with this flu don’t necessarily look sick. In short, the precautions that are being shuggested by State Fair officials and the State Health Department are not expected to be effective.

Are you, Greg, going to the State Fair?

Of course. But I will not be visiting the Big Pig or his little friends. Nor will anyone else in my family. We will not, however, be avoiding swine entirely. If there is Bacon on a Stick, that will be good. Or corn dogs. I believe they include pig.

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