Back when I first learned about vaccines, umpteen decades ago, we were taught that a vaccine immunized one from infection by a pathogen, and that was more or less full-stop, at least for us non-medical types.
Now we’re talking about breakthrough infections, which are the occurrence of an infection in a person fully vaccinated against Covid-19, and, well, this:
“When you hear about a breakthrough infection, that doesn’t necessarily mean the vaccine is failing,” [Dr. Anthony] Fauci said. “It’s still holding true [i.e., working], particularly with regard to protection against severe disease leading to hospitalization and deaths.” [WaPo]
That led me to muse on to how there are three domains to think about here:
- Infection, where your cells are successfully invested by the pathogen.
- Infectiousness, in which the pathogen is successfully using your cells to reproduce, mutate, and spread to its next victim.
- Disease, which is the symptoms, from sniffle to death, that is experienced by the victim as a consequence of infection. [My thanks to Dr. Harriett Hall for the difference between infection and disease; I’ve lost the relevant link.]
Success is a spectrum word here, where success can range from just a little bit of success penetrating the cells targeted by the pathogen, all the way to optimal penetration and subversion of their function to the pathogen’s purposes. The ability to reproduce and infect another host seems to correlate, at least in Covid, with the success of the infection; so, it appears, does disease.
All of this leads to this useless bit of word play:
Vaccines lead to sickly infections.
Sure, go ahead. Wrap your mind around that one.
