flunking my test

Someone posted a very odd question on Facebook the other day. "What did you learn in school that you have never used in life?"

The answers were the usual suspects on the Never-Used list: algebra, biology, Latin, math, physics. I am certain some teachers were weeping into their tea that morning because, in reality, everything we learned in school has become part of the way we think. Sometimes, it merely means dusting off the cobwebs.

Today's trip down memory lane will be high school biology.

The presence of the coronavirus in our lives has created an avalanche of news stories -- especially around the issue of testing for the virus. There are essentially two types of tests. One that indicates a person is suffering from a current viral attack. The second is an antibody test that indicates a person has been exposed to the virus in the past.

When I returned home to Mexico from Oregon in early March, I came down with some infection that kept me in bed for almost two weeks. It started with a surge of diarrhea accompanied with a debilitating headache. My joints ached along with my chest. I lost my senses of taste and smell. And every time I stood up, I was incredibly dizzy. As luck would have it, WHO had just added a couple of those symptoms to the coronavirus list.

By the time I could make my way to the doctor, most of the symptoms had receded, but they had been replaced by a consuming fatigue. The fatigue was bad enough that I drove to the doctor rather than taking my usual walk.

We talked about several possible diagnoses. My doctor doubted I had contracted the coronavirus because my lungs were perfectly clear. At the time, there were no tests locally to rule out the virus. The fact that my joint pain passed so quickly ruled out the three mosquito-borne disease. And, even though the symptoms sounded like a resurgence of my cellulitis, there were no signs of that.

After about three weeks (two weeks in bed), I was as fit as I had been before whatever it was had hit me. The possibility that I might have had an early case of the virus hung around in the back of my mind, but I pretty much ignored it as a bit of academic interest.

That changed when our local laboratory in San Patricio received a shipment of antibody (post-exposure) tests.

Because you all learned this in your high school biology course, there is no need to go into a lot of detail about antigens. But here is a comic book version.

When the body is invaded by disease-causing organisms, the body reacts by creating soldiers to fight the invasion (antibodies). After the disease is defeated, those antibodies remain in the body prepared to fight a similar invader. That is why people who have suffered one strain of flu may retain some immunity when the same strain rolls around again.

The theory is that once a person has been exposed to the coronavirus, a specific antigen will be formed in the body to fight that disease, and that some of those antibodies may survive after the disease passes.

Even though I knew there were problems with the antibody test, I decided to take one. After all, it might let me know if I had developed some antibodies to deal with what will most likely be recurring waves of the disease.

So, into the lab I went on Friday. I paid my one thousand pesos (less than 45 dollars), the technician drew my blood, and I was sent on my way. An hour later, I had the test results and a receipt on my telephone. Mexico's medical system is that up-to-date.

I was disappointed. The results were negative. But I was not surprised. My friend Rick Noble, who arranged for the installation of my solar array, and his family had suffered similar symptoms to mine about the same time. They were as positive that they had experienced a bout of the coronavirus as was I.

We were all wrong. All of the tests turned up negative.

I mentioned earlier there are problems with the antibody test. The false negative ratio is as high as 15%. That may not sound like much, but it is a far larger margin of error than most tests approved by government agencies. Some agencies have discussed decertifying the tests for that reason, but there is not currently an alternative.

A number of governments once discussed the possibility of issuing post-lockdown health passports to people who tested positive on the antigen test, on the theory that they would be immune from a second infection and they would not be carriers of the disease. Those plans have been scrapped for two reasons.

The first is the combined false positives and false negatives inherent in the current tests. The second is that it is far too early to know how long the antibodies remain in the body. There have been some preliminary studies that show some immunity exists for an undetermined amount of time. But it will be a long time before double-blind peer-reviewed studies can be conducted.

The passports remain on hold.

I suspect Rick's family and I simply had one of the many nasty infections that are passed around the villages here. And even though not all infections come from the north, many accompany northern visitors, as happened with my infection that I brought from Seattle. As a result, we are just as likely to contract the coronavirus as anyone else.

It was a small hope.