Mutant Swine Flu Pandemic Possible - But Don't Panic

"World Health Organization: Swine flu could spread globally"
CNN (April 25, 2009)

"The presence of swine flu in Mexico and the United States is "a serious situation" that could develop into a pandemic, the World Health Organization's director-general said Saturday.

" 'This is an animal strain of the H1N1 virus and it has pandemic potential because it is infecting people,' Dr. Margaret Chan said Saturday speaking to reporters by phone.

"In Mexico, 68 people have died from swine flu, according to a statement from the U.S. Embassy in Mexico...."

I get curious when a news article mentions half of an important set of data, but not the other half. That many people dying is serious: but we can't know how serious unless we know how many people got the bug in the first place. The total number of cases in Mexico seems to be "around 943 nationwide." (FOX News)

Now we have a little more data. The articles were published two days apart, using different sources, and this is a very rapidly developing situation: so I take the 68 deaths / 943 cases ratio as very approximate. Still, it looks like very roughly 1 in 14 people who got this version of swine flu - and were diagnosed - died.

That's bad.

Particularly since this type of swine flu can apparently be passed from person to person (WSJ blog). Swine flue normally infects people who are in contact with pigs. (Which makes this up close and personal for me: raising pigs is a major part of the local economy.)

There used to be "swine flu vaccines." Then, in 1976, roughly 1 out of every 80,000^corrected people who got the vaccine develped Guillain-Barré syndrome (GBS). That's six times the usual rate. ¹ Nobody could show that it was the swine flu virus in the vaccine that caused GBS, but we stopped using it anyway. And the association of GBS with flu vaccinations stopped.

I could write something about today's America being risk-averse, but I've done too many overly-long posts this week.

If You're Concerned: Wear a Face Mask in Crowds, Wash Your Hands, and Stay Away from Pigs

Seriously: That's pretty good advice, if you live in an urban area where the new swine flu is making the rounds.

In Mexico City, "Authorities advised capital residents not to go to work if they felt ill, and to wear surgical masks if they had to move through crowds. A wider shutdown - perhaps including shutting down government offices - was being considered." (FOXNews)

Staying away from pigs probably won't do much good with this new swine flu, though.

Attack of the Mutant Virus - No, Really

Pigs can catch avian, human, and swine influenza viruses. (Just like us.) When different types of flu virus infect a pig at the same time, they can swap genes. That's happened this time.

The new strain's DNA comes from North American swine influenza, avian influenza, human influenza and a sort of swine influenza that's usually found in Asia and Europe. And, just to make things more interesting, this viral champion of diversity seems to be resistant to antivirus drugs.² (CDC, CNN)

Health Tip for the Day: Stay Inside and Watch Television or Surf the Web

I'm going out for a walk right after I finish this post and chat it up: but I'm slightly serious about that advice.

One reason that this mix of avian, swine, and human virus is such a problem is that people travel. A lot.

Information Technology is at a point now where quite a bit of business can be done over the Internet: everything from sending a proposal to videoconferencing. (If that sounds unlikely, consider this: my spellchecker accepted "videoconferencing" as a word. We're living in 'the future' now.)

I don't find it too hard to imagine a world where people live the old-fashioned way, never (physically) traveling more than a few miles from where they were born: but routinely communicating with people around the globe. I suppose there will be people who insist on seeing the Matterhorn and Singapore with their own eyes - but I'm getting off-topic.

WHO Alert Phases: Say What?

News articles mentioned health alert levels, sometimes indicating that they had something to do with WHO (World Health Organization). I did a little digging, and found this:

WHO Alert Phases:

1. Low risk of human cases
2. Higher risk of human cases
3. No or very limited human-to-human transmission
4. Evidence of increased human-to-human transmission
5. Evidence of significant human-to-human transmission
6. Efficient and sustained human-to-human transmission

Right now, globally, were at "3." (pandemicflu.gov)

Background and more information:

• CDC (Centers for Disease Control and Prevention)
  • "Human Swine Influenza Investigation"
    (April 24, 2009)
  • "Key Facts about Swine Influenza (Swine Flu)"
  • "Swine Influenza (Flu)"
  • "Swine Influenza in Pigs and People " bochure (pdf)
  • "Influenza (Flu)"
    
• "Mexico Links Sickness, Deaths to Swine Flu"
  FOXNews (April 24, 2009)
• "Swine Flu: Look Hard Enough, and You’ll See Strange Things"
  Health Blog, Wall Street Journal
• "Influenza Virus Vaccine (Subvirion) (Intramuscular Route)"
  Mayo Clinic Staff
  • (Somewhat technical, but informative.)
• "What are pandemic alert phases and what phase are we in?"
  pandemicflu.gov
  • With link to relevant WHO page

List of posts relating to swine flu:

• "Swine Flu 2009"

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¹No: That doesn't mean that vaccinations (swine flu or not) cause GBS.

"Six times the usual rate" refers to the fact that, if something else doesn't kill them first, a tiny fraction of people get GBS - vaccination or no vaccination.

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²UPDATE (April 25, 2009)

Thanks to bnsullivan, for this post:

• "Swine Flu: Looming menace or a blip on the epidemiological radar screen?
  Virtual Scratchpad (April 24, 2009)

This post seems to be well-researched and common-sense. Also has link to WHO report which clarifies the 'antiviral drug resistant' nature of the new swine flu.

Sample paragraph:

"...Here is another worrisome point: The World Health Organization (WHO), which also issued a brief report on human Swine Flu infections on its website today, notes, 'The Swine Influenza A/H1N1 viruses characterized in this outbreak have not been previously detected in pigs or humans.' In other words, these outbreaks appear to be caused by a novel pathogen...."

The quote is from "Influenza-like illness in the United States and Mexico" (WHO (April 24, 2009)). The WHO report paragraph is a sort of good news/bad news situation:

"...The Swine Influenza A/H1N1 viruses characterized in this outbreak have not been previously detected in pigs or humans. The viruses so far characterized have been sensitive to oseltamivir, but resistant to both amantadine and rimantadine...." (WHO)

So: This is a not-seen-before virus. It's resistant to two antiviral drugs. On the other hand, it isn't resistant to another.