Or a placebo. As I indicated in last week’s column, I volunteered and have been chosen to participate in the clinical trials of a COVID vaccine. Yesterday I received the first injection, despite the exhortations and exclamations of the anti-vaxxers.

About 30,000 patients are in the trials for this vaccine developed by pharmaceutical giant Pfizer and its partners. (Big Pharma is evil until we need a new life-saving drug, huh?)

The particular clinic that injected me is a third-party clinical trials company engaged by Pfizer. It’s performing about 200 injections over the course of six weeks. That means there are hundreds of such clinics around the country. So far, my clinic has done 30.

It takes a couple of hours for each patient to read and sign liability waivers and other formwork, and for a brief medical examination by a physician, lots of explanations, blood draws, the injection and then about 20-30 minutes waiting around to see if you keel over. I did all of that except the keeling over.

In fact, I still feel no side effects at all. I’m actually disappointed, because side effects would suggest that I’ve received the vaccine and not the placebo that is given to 50% of the patients. They don’t reveal whether you received the vaccine or the placebo until the study is later “unblinded.”

Spidey Powers or at least a touch of priapism, or both, would have been nice. But nothing happened.

On the other hand, in response to my question, they said only one of their 30 patients so far (which at the 50% rate would equal about 15 patients who’ve received the actual vaccine) reported any side effects. So it’s entirely possible that I did get the vaccine, but it’s producing hardly any noticeable side effects. That would be good.

I learned at the clinic for the first time that they pay patient volunteers $120 for each of six to eight in-person visits and another $5 each time I fill out the daily patient “diary” in the smart phone app they’ve given me.

I think paying money to volunteers isn’t quite right and I’ll probably donate the money, but I suppose they need to pay money in order to get the “volunteers.” What a sad commentary.

In my down time at the clinic, I did some back-of-the-envelope statistical math. In America, nearly 2% of the population are known to have gotten the virus, which equals nearly 6,000,000. (The number who’ve died of it is a small fraction of that.) If that same infection rate of 2% applies to the 30,000 patients in this trial, that means about 600 should get the virus if the vaccine doesn’t work at all – about 300 from the vaccine group and 300 from the placebo group.

What they’re hoping to see, of course, is about 300 cases from the placebo group and zero from the vaccine group. But they’d be happy if the vaccine group merely produced some number well less than 300. The physician who briefly examined me thought the efficacy would be around 70-75%. I don’t know whether his view is a well-informed one, but if he’s right then the 300 expected cases in the vaccine group will be more like 100. If that happens, and side effects are tolerable, we’ll have a vaccine.

The actual number of people in America who’ve contracted the virus is probably way more than 2%. It could be more like 20%. If so, the trial results will be all the more meaningful. To a statistician, a split of 1,000 versus 3,000 between the cases in the vaccine group and the cases in the placebo group is more meaningful than a split of 100 versus 300.

One important thing we don’t know yet is how long the vaccine will work. In other words, when do the antibodies fade away?  In measles, the antibodies last for life but in other diseases they don’t. Very early data about COVID is encouraging, however, and it would be unsurprising if the antibodies last for a year or more.

This is not a “challenge trial” where they deliberately expose the patients to the virus to see if the vaccine prevents infection. Challenge trials are usually considered unethical for viruses that are life threatening and for which there’s no sure-fire treatment. Putting an untreatable deadly virus in a patient who took the placebo or took a vaccine that is less than 100% effective (and none are 100% effective) could kill him.

Instead of a challenge trial, in this trial the patients just go about their ordinary lives. The trial hinges on enough of them getting exposed to the virus in their ordinary lives to get meaningful statistics on the performance of the vaccine versus the placebo. That’s why they need 30,000 patients – so that a statistically significant number of placebo and vaccine patients get exposed to the disease by happenstance.

Back to the anti-vaxxers. I continue to be impressed by them. Not by their science, because they offer none. But by their faith.

You might think they’d be thankful that I’ve volunteered for a clinical trial they think is highly dangerous, because it might produce benefits to them and to society with no attendant risk to them personally. But no, such rational thinking is swamped by their blind faith that vaccines are evil and their anger that I’m a heretic for thinking otherwise. Oh well.

The next step, assuming I continue to dodge that keeling-over routine, is to go back for a second injection in three weeks. It’s thought that these vaccines will ordinarily require two injections to produce a really robust immune response.

Sometimes side effects manifest from that second injection. I’m hopeful.