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Swine flu: here we go again

update below

The news is spreading everywhere: Mexico flu ‘a potential pandemic’. In the next few days we’ll probably have a replay of the bad old bird flu days. Tamiflu! Hide in your house! Shoot the postman! Or whatever level of idiocy we achieve this time.

I did one of my POPs (Pissed Off Posts) on that occasion, and I think it’s time for a rerun. electron micrograph of a flu virus in cross section

First, this newest flu strain, H1N1 (CDC info), sounds vicious. It’s communicable between people (in the US, as of this morning, there were 11 cases with no fatalities) but it’s already killed dozens of people in Mexico. This makes it a far more serious threat than bird flu, which was almost never caught from another person. So being worried about this new flu is not a mark of loopiness in the same way as setting your hair on fire over bird flu. But panic is still an intensely foolish reaction, and the points I’ll run through below are still valid.

Fiction 1: We’re all going to die. It makes for a good movie script, but this is not the way flu works. Even SARS, which had an exceptionally high rate, had about 15% fatalities. Obviously, the only good rate is zero. The point I’m trying to make is that exaggerating risk does not help anyone to deal with it.

Fiction 2. Quarantine will stop the disease. Imagine two different scenarios. You feel the first twinges of something that could be flu. In the first scenario, you go to the hospital, get tested, receive free medication, your whole family and all your contacts are tested and also receive any necessary medication. People who see how you were treated are also alert to any sign of flu and go to get treatment as fast as possible. In the second scenario, you go to the hospital, and get tested. Then you’re quarantined for an unspecified length of time, your family is quarantined and unable to go to work, pay the rent, go to school, or do anything they have to do. The money spent on finding and quarantining you and yours is not available to provide an adequate supply of drugs. Obviously, in the second case you’ll rush to the hospital at the first sign of flu. Not.

Quarantine is useful in some situations that epidemiologists know all about. They’ll tell you when quarantine is necessary. Really, they will. Public hysteria is never useful.

Fiction 3. I’ll take Tamiflu and save myself! No, you won’t. Save yourself, that is. Here’s why.

Flu viruses mutate. Flu viruses mutate a lot. They develop resistance to antivirals incredibly fast, much faster than bacteria do to antibiotics. Way back in 2005, in the bird flu days, this was already a problem, and Tamiflu had barely been invented. Flu viruses are growing resistant to antivirals: “…in a special online edition of The Lancet, scientists at the Centers for Disease Control and Prevention reported that 12% of influenza A strains worldwide have developed resistance to the most widely used flu medications.” (That referred to A-series, not H-series, viruses and not to Tamiflu specifically, but the principle is exactly the same.)

So, by trying to take care of number one, instead of everyone, we’ll end up breeding resistant disease, potentially in a matter of weeks, and we’ll all be defenseless, including the people who took it “preventively.”

When is it sensible to take an antiviral? When it is part of the public health measures to contain an outbreak. On an individual level, it’s prescribed preventively when you or someone you live with has a diagnosed case of flu. This is the main reason why outfits like the CDC don’t stock enough doses of antivirals for “everyone.” We don’t need enough for everyone. We need enough to blanket regions with outbreaks, and we need those viruses not to be already resistant to the only drugs available because people have been using them wrongly.

Another consequence of viruses’ rapid mutation rate is that new lethal strains appear all the time. Case in point, H5N1 bird flu in 2005, H1N1 swine flu in 2009. That’s another reason why quarantine, by itself, doesn’t solve the problem. All you’re doing–if it works!– is putting out brush fires, while the viruses keep pouring on fuel just out of reach.

So, that’s what not to do. What are the sensible things that actually work?

First and foremost: vaccines. Obviously, we don’t have a vaccine for this new strain yet, and it’ll take several months before we do. Once it’s available, that’s the most effective protection and the best way to stop the spread (since the virus can’t hop from person to person as easily).

Once there is a vaccine, there’s a useful priority list as to everyone’s place in the line. It really helps to control the spread if people help with that. The most vulnerable people need to go first because they’re the likeliest to catch it and, therefore, to spread it. That puts everyone in greater danger. The priority is, more-or-less in order, frontline public health workers (nurses, ambulance drivers, and the like); school-age and day care-age children (the main vectors); the elderly, infants, and the immune-suppressed; people who deal with the public a lot (teachers, hairdressers, police, funeral workers, and so on), and, finally, the rest of us.

The next most useful thing is not to spread virus particles around. (I mean, duh, right?) The problem is we still don’t really know how they’re spread. The CDC thinks droplet infection (i.e. by air) is an important route. Other research points to touch as the main route. E. g. a BBC report on a study by Oxford & Lambkin, Journal of Infection, August 2005, pages 103-9.

One proven source of droplet infections is airplane trips. Since air travel is by far the biggest way viruses hop continents and spread long distances, I’d say that forcing the airlines to deal with their bad habits is right up there with vaccination as an important preventive measure. The airlines really are part of the problem. It’s not just a matter of many people in close proximity for a long time. The airlines save money by recirculating air without filtering it well enough, by keeping the air too dry because that’s cheaper, and by keeping its oxygen content too low, likewise because that’s cheaper. Airlines should be kicked, repeatedly, until they do what is necessary for the safety and health of their passengers and flight attendants.

For the rest of us, however, the most effective ways to stop the spread are:

1) Stay home at the first sign of sickness. That, up to the point when the disease peaks, is the time of highest infectivity. (I know. The feeling tends to be, “I’m already sick. I can’t get any sicker. And I’m sure not wasting any days off on this.” Or, “I have an exam. I have to go to class.” It’s another case where worrying about number one makes it worse for everybody, including eventually number one.)

2) Wash your hands or use alcohol wipes after touching doorknobs, phones, toilet handles, and anything else touched by many different people. Basically, you should be cleaning your hands about six times a day. The next most important thing is cleaning and disinfecting surfaces that are touched often (counters, phones, desks, etc.). The virus is activated when virus-laden fingers touch our mouths, nose or eyes. It is truly amazing how difficult it is not to touch one’s face, and how unconscious and automatic the process is. One of the interesting effects of wearing rubber gloves is that you find out how often you touch your face. Most face masks are useless for stopping viruses. Viruses are tiny. They’re just big molecules, after all. Any face mask that is easy to breathe through has a pore size that looks like chicken wire to a virus. However, what face masks can do, and do very effectively, is stop you from touching your nose or mouth.

So, as the hysteria mounts in the next weeks and months (unless we’re lucky and this bout is caught early enough so that it fizzles) remember what you know. There’s no need to shoot the postman. It wouldn’t help anyway. There’s no need for any heroic high noon standoffs at the OK Corral pharmacy for the last magic pills. Just wash your hands and don’t panic. (If you need to do something violent, kick the airlines.) And tell everyone you know to do what works instead of what feels good.

Update April 26, 5 pm: Then again, the BBC has a series of very worrisome comments from a whole series of people in Mexico City and Oaxaca, many of them health professionals. Not good.

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