Swine flu---don't panic

So far, it looks like the US Gov't is on top of this one. If you're interested in following along with the story, I strongly suggest following the Effect Measure blog. The writers know their stuff, and so far, government websites aren't all that much health.

Some basics:

As you remember, the flu virus changes over time due to "antigenic drift" and we need to make new vaccines every year. Sometimes, often due to multiple strains co-infecting the same animal, the influenza genome undergoes a more dramatic change called "antigenic shift". Influenza A is commonly found in birds, pigs, and humans. If strains from different species co-infect say, a pig, the genes can undergo some mixing (to be completely un-technical) producing an antigenically new strain which may then move back to other animals.

In the current case, it appears as if a swine flu virus underwent some of these genetic shenanigans and then moved to the human population. Since the strain is new to us, immunity is low. It does appear that this new swine flu strain is being transmitted from humans to humans, which is not always a given---many strains are limited to one species, or can only move from a particular species to another.

So what we may have here is a perfect storm of sorts; a flu virus to which we have little immunity (this year's flu shot won't cover it), and an ability to pass it from person to person. Still, this doesn't mean it will be some horrid medieval killer. Yes, the number from Mexico are discouraging, but so far at least, the impact in the States has been minimal. This is certain to change, but where it will go from here is unclear.

The flu isn't magic. It's a virus we see every winter. It passes through respiratory droplets, so if it hits hard, masks and frequent hand washing will go a long way. Drugs exist to treat these infections, and the U.S. has an additional emergency stockpile. Also, hospitals and local public health departments have emergency pandemic plans (which we will hopefully not need). Unfortunately, the only way to really know how well (or badly) we've prepared is to get hit with a pandemic.

We may have that chance.

More like this

Last year's flu season was bad. Hopefully this year's will be better (for us, not for the virus). The CDC is changing the recommendations a bit to improve the population's coverage, and I'm hoping I won't be quite as busy this winter. Last year, I provided you with weekly flu activity updates…
Last week another expedited-review paper appeared in the high profile journal Science, this one summarizing the genetics of the novel H1N1 influenza A virus causing the current outbreak cum pandemic. This time there is quite a bit of interesting material in this paper for non-virologist scientists…
This afternoon CDC held a "media availability" on the evolving swine flu cases. Evolving is an understatement. There are now more recognized cases, although not all cases are "new," with some cases retrospectively recognized now that more intense investigation is occurring. The total is now seven…
Novel Swine Influenza Virus Subtype H3N1, United States In several of my influenza posts, I've discussed ways that the viruses can evolve. These are termed "antigenic drift," where the virus accumulates small mutations in the RNA genome; and antigenic shift, where large sections of the genome are…

Luckily I made it through the winter with not even a cold. Today is suppose to be 90F in Maryland. With my father being a career ex-soldier, I remember in the 70s where all soldiers had to take a Swine Flu shot. Not anti-vax, but the shot did cause the death of a number of our soldiers, to the point that a number sued to government so they would not have to take it.

I'm wondering if we might be spared an epidemic because it's approaching summer, and most of us aren't closed up in offices, buildings, schools etc. I can't remember if the reasons for most flu epidemics being in the winter was because of the close contact, or it happened for unknown reasons, and I'm recalling some urban myth.

the reason behind seasonal influenza isn't clear. see scienceblogs.com/effectmeasure and check out the flu cat

There has been a lot of back-and-forth on the issue of wearing masks. People have stated with certainty that it provides no benefit, and other people have stated with certainty that it's very effective. What's your opinion?

Evidence isn't great one way or the other but expert consensus is for masks, but N95 vs reg surgical masks isn't well known either

After the federal gov't made a mess of the Katrina response, I'm sure the new administration is working very intently to appropritately respond to this outbreak.