“Titer” Tests and Why They Matter

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We’re all learning a bunch of medical terms we didn’t know (and had no need to know) before. There’s one term which hasn’t come to the forefront yet, but will, and that’s “titer test.”

Most of the people I know who are familiar with the term live in the horse world, for reasons I’ll explain. But we might all end up being intimately familiar with titer tests. Don’t worry. They aren’t that scary.

What is a Titer Test?

There are two other terms that you might also hear: Antibody test and serological immunity test.

Which might make it clearer. A titer test is a test to see if you have antibodies against a disease or infection. (The reason horse people are familiar with them is because there are some horse vaccinations that are really expensive so it’s often cheaper to get a titer test to see if the last one has worn off yet).

Titer tests are most often used to determine whether somebody needs a booster shot or whether a vaccine is working. But they can also tell if you had a disease. This is different from the COVID tests everyone’s fighting to get; those can tell if you have the virus in your system. A titer test can tell if you have COVID, but only about five days or more after you develop symptoms.