Blessed by the Potato

One of the first great breakthroughs of evidence-based medicine was Semmelweis (and again Lister) discovering the vast improvement in patient outcomes when doctors wash their hands. “Hand hygene” is one of the cheapest, best ways to prevent disease transmission, whether from doctor to patient, or from the environment to your mouth during flu season. Yet it’s very difficult to get people to actually do it every time.

How often do you see people leave the public washroom without washing their hands? Yes, Penn & Teller demonstrated that your hands were probably dirtier before touching your junk that’s been safely & cleanly ensconced in your undies, but nonetheless, it’s important to wash your hands regularly, and that’s the socially accepted time to do it.

I understand that it is difficult for healthcare workers — after washing my hands 20 times per day I’m definitely reaching for the hand cream when I get home, so up to a hundred times a day has got to be killer. But hey, hazards of the workplace and all. Deal.

Outside of the hospital, soap and water aren’t always readily available or convenient, so alcohol-based hand sanitizers have been installed, which I think can only be good, especially in schools and malls. When these things first came out (around SARS), I had serious doubts as to how effective they could possibly be — after all, even if they killed germs, they’d still leave everything on your hands. Of course, at the time, I was working in a wet lab and was more concerned with chemical contamination than bacterial. For preventing the spread of disease though, they look to work just fine (but I am too lazy to review the literature at this time).

Freakonomics had a blog entry about handwashing compliance and in the comments, one person was concerned about the possibility that all this hand sanitizer use would lead to bacteria developing resistance to it. As one reply so elegantly put it, that would be like humans developing resistance to being doused in gasoline and set on fire. That’s not to say that some bacteria won’t escape, especially if you miss a spot, or don’t use enough to get into the fissures of your skin… that’s just not likely to be an inheritable trait.

Speaking of fire: Yes, alcohol is flammable. Incredulously, I heard that some schools were banning, or considering banning, hand sanitizer for this reason (and also for the “martini dispenser” issue). I wondered though if gelled alcohol was flammable. Sticking my head in the kitchen and uttering those words that always make Wayfare cringe in fear — “Wanna do Science?” — I set out to test it experimentally. With a lighter, I could set some hand sanitizer on fire. That’s still not a particularly good reason to keep it out of schools (I’m not a fire expert, but it didn’t really seem all that much more flammable than paper, and paper doesn’t evaporate in seconds). Vigorously rubbing my hands together (the intended method), did not start a friction fire.

Dear readers, please indulge me. Follow these instructions, and post your results (anonymously if you wish) in the comments or by email:

“You can measure your head size with a tape measure, going around the circumference of your head, just above the ears. ”

It shouldn’t take you very long.

There is a device that the government has tried to put around the neck of every person in the country. It looks innocuous, but it can cause bruising, interfere with napping, and while it may have been a handy tool in the 60s, there’s insufficient proof that they’re so needed in modern life that the government should be forcing their universal use. On top of that, adjuvant devices have been mandated recently as well, and these can cause really nasty burns, fractures, and other miscellaneous injuries, even if the person wasn’t at serious risk of the thing they were designed to protect against! In fact, they can make things exponentially more hazardous for first responders trying to help you!

Do you want the government forcing these devices into your life? Into the faces of your children?

I am, of course, talking about seatbelts and air bags, something you’d never consider buying a car without. But if you pitch the rhetoric the right way, look at the side effect risks without considering the benefits, and throw in a touch of paranoia about the government, then suddenly you’re not so sure you want those things in your life.

And so it is with vaccines: they’re not perfect, there is a side-effect spectrum. Unfortunately just due to the nature of the beast, any vaccine for the flu strain threatening us with a pandemic, H1N1 this time around, has been rushed to market. If it wasn’t rushed to market, it wouldn’t be specific to the strain that most recently evolved. We’re not going to have perfect information about the safety profile. We’re not going to have perfect information about the effectiveness since, after all, if we waited for that it would be too late for a vaccination program to work. That’s not to say that this is a shot in the dark — we know in general that vaccines are quite effective, and we know that in some large trials the antibodies against H1N1 were successfully produced by the people vaccinated. It’s just that it’s nearly impossible to meet the standard of evidence that some of the people standing up against vaccination are demanding. In this case you should not take the absence of definitive evidence as evidence of an absence of effect.

Fortunately, vaccines really aren’t that different from one another in their general side-effect profile. What will vary will be how many people get the specific illness from the vaccine (i.e.: if any live viruses get through and actually infect people), and how effective the vaccine will be. Which, as I said, probably will never be known until long after the window for vaccinations has ended.

It’s a gritty, uncomfortable situation to have to make potentially life-or-death risk-benefit decisions on such very imperfect information, and not what we generally expect from our doctors. But that’s all we’ve got.

And there is a lot of hype going on about the flu, and the vaccines, and it’s all a little much to take in.

For the H1N1 pandemic fears itself, I think that the coverage is a little over the top, but just a little. This is a fairly nasty strain of flu that kills young, healthy people — not just asthmatics and the elderly like most flu strains. There is something different about this strain than the regular seasonal flu. It’s deadlier and more contagious than is typical. On the other hand, it’s not turning out to be as deadly as it looked from the first cluster in Mexico (it’s not SARS-bad).

Some of the groaning about overhyping comes from the fact that Avian flu (H5N1) was over-hyped so much just a few years ago, but no pandemic came of that! Things are a little different this time around: Avian flu had the potential to cross the species barrier into humans, and was highly contagious… but was mostly contained to birds. Swine flu though is spreading person-to-person, and it’s in Canada (with nearly 100 deaths already). It’s still early and we don’t have a good idea of the total number infected, but the death rate appears to be about 10 times higher than a typical seasonal flu. People are stupid, and forget basic things like handwashing and not coughing on people on the bus, so I figured that a little bit of hype isn’t a bad thing from that perspective.

Hype can be damaging — people have very little patience, so if a pandemic doesn’t materialize in their community soon, they’ll start tuning out the message. On the other side of the spectrum, pandemic hype can lead to people not travelling, not eating out, etc., which can be costly to an economy already on the edge.

I’m not an epidemiologist, but looking at the data that’s out there now and doing a back of the envelope calculation, it looks like we’re on track to have 50,000 deaths in Canada as a result of H1N1 by the end of 2010, unless something changes (such as the vaccination program — all the deaths so far have of course occurred before the vaccines were available). So you tell me, is that potential worth the hype?

Thanks to our near-miss with SARS, hospitals in Ontario are well equipped to handle infectious diseases. Proper respirators are well-stocked, training courses have been given and repeated, and patients are screened for fever as a matter of course. The first few days of the vaccination clinics here have had very large response rates, with people lining up for hours to get the shot early. I believe that thanks to the hype (& vaccines) Canada will probably be looking at around 10,000 deaths by the end of this — about twice as bad as a typical flu season. Some will of course look back and wonder what all the fuss was about, and others will be glad we’re not in the parallel universe that did have to find out the hard way how bad things can get.

The Daily Show (an often surprisingly level-headed source of news and commentary) had a little bit on the H1N1 vaccine last night which I recommend you give a quick watch (available online for Canadians at http://watch.thecomedynetwork.ca/the-daily-show-with-jon-stewart/full-episodes/the-daily-show-with-jon-stewart—october-15-2009/#clip223053 — Americans can watch Hulu, the bastards).

This reminded me of a question one of my cousins asked recently about the vaccine: what’s an adjuvant, “’cause I’m not able to find much positive about it.”

Indeed, if you just search the internet for information about the health effects of the various adjuvants used in vaccines, it looks like pretty scary stuff. That’s because an adjuvant is designed to trigger an immune response; to make your body’s immune system go into over-drive so that it will recognize the viral matter in the vaccine and produce antibodies against it. The risks include getting a fever or other flu-like symptoms, an allergic reaction, or even a very remote risk of developing certain autoimmune disorders like rheumatoid arthritis. If you just read up on the adjuvant alone, it sounds like something you’d never want to have in your body — but it’s only a small amount, and it’s necessary to make the vaccine effective (esp. in a single dose so you don’t have to keep going back for booster shots, which might work for hepatitis or tetanus vaccines, but doesn’t fly in the face of a potential pandemic).

“So if I don’t want those risks, don’t take the vaccines.”

Ah, well, there’s the tricky part. The risks are remote (aside from the mild cases of feeling unwell or having an acute allergic reaction), and the benefit is that you don’t get the virus you’re vaccinating against, or carry it to pass on to other people (such as seniors or those with compromised immune systems). On an individual level it can be a tricky mental calculation: on the one hand, psychologically it’s less desirable to subject yourself to something with risk before you have to, especially since it’s unknown and kinda scary. Whereas hey, you’ve had the flu before, how bad could it possibly be? Plus you can take steps to prevent yourself from getting the flu, such as wearing a space suit, or never leaving your basement, but once that shot is in your deltoid, that’s it cowboy, enjoy the ride. These psychological factors can really skew the perception of risk from the actual risks. It doesn’t help either that it’s new so there isn’t the years of testing that other vaccines have, or that there are people out there spreading the conspiracy theories that the government has put mind-control drugs in the vaccine (what, you think if they had those they wouldn’t have put it in your MMR vaccine as a kid??).

Of course, from a societal stand-point it’s a no-brainer for virtually every vaccine, including the one for the flu: society is better off when a large part of the population opts to be vaccinated. Even on the individual level the actual risk arithmetic (as opposed to the perceived risk) is also usually soundly in favour of getting vaccinated.

Update: LOL, Ben actually beat me to it with a post on the swine flu vaccine. He takes the opposite POV :)

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We’ve been doing some training lately, preparing for the worst. Specifically radiation disaster management. It’s a pretty interesting course, with some good take-home messages.

The first is that dealing with the (terrified) public can often be the hardest and least predictable part of disaster management, and in a radiation disaster situation that can be pretty bad. The public generally has exceptionally poor knowledge of what radiation is, how dangerous it actually is (yes, people have died, but it’s not nearly as dangerous as people are afraid it is), and what the difference between contamination and exposure are. We’re told that we have to explain physics concepts to the public at a grade 6 level, and that can be quite the challenge. Especially when you also have to deal with an attention span of maybe 1 minute. That speaks to me of a need for more general science outreach and education, something I’m all in favour of all the time (aside: notice the “science questions” topic tag — feel free to ask any, as this kinda sorta counts as a scientist working on educating the public ;)

For those of us worried about potential future terrorist attacks, there are a number of frightening scenarios thrown around. That of a dirty bomb or even a full-blown nuclear attack often top the fear lists. However, as our instructor today said, “I hope to hell that nothing happens, but if there is an attack, I hope it is radiological. We have detectors that go ‘beep’ at even very safe levels of background radiation. We can fairly quickly and very reliably screen those who have and have not been contaminated. We don’t have a meter for germs or nerve agents.”

Of course, we have to deal with the fear that the word radiation inspires. Sarin nerve gas is deadlier than the radiation in most dirty bomb scenarios, but thanks to poor delivery the attacks on the Tokyo subway resulted in only about 1000 casualties of some sort (those moderately ill with vision problems) as well as the 12 dead. For every sick person that showed up at a hospital tough, five more “worried well” came in to be checked out. So that’s going to be a huge issue with radiation, and hospitals are somehow going to have to deal with screening and even just corralling the thousands of frightened people.

An even bigger issue to deal with is the fear in the healthcare workers and first responders. Before training, many healthcare workers are afraid of radiation, and wouldn’t want to work on a person coming from a disaster or dirty bomb attack for fear of being contaminated themselves. Fortunately:

No caregiver in the history of radiological accidents has received a medically significant dose of radiation from treating a contaminated patient.

That includes the doctors and nurses who treated the firefighters at Chernobyl. It includes the rescuers at the SL-1 disaster. Now, that’s not to say that the environments can’t be dangerous — many firefighters did get excessive doses from going into the reactor at Chernobyl*. It’s not to say that it can’t happen that someone could get so contaminated that they’d put the rescue crews at risk, but it is exceptionally unlikely, and hasn’t happened yet.

* – a big part of that was poor training and misinformation: many of the figherfighters didn’t know it was a nuclear situation, they didn’t have the proper equipment or procedures in place to protect themselves — I can’t find a reference, but I’ve heard they weren’t even told to strip off their contaminated outer clothes after exiting the reactor. The USSR was too secretive for anyone’s good.

So for medical teams the issue becomes one they’re familiar with: stabilize the patient medically. Airway, bleeding, circulation. Only after those are taken care of do you worry about potential contamination and cleaning it up.

“There are no points for clean corpses.”

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