His is a good article on immunity gained by exposure vs vaccine alone vs both:
A new study from Israel suggests immunity gained after recovering from a previous COVID-19 infection is more protective against the new Delta variant than vaccine-induced immunity. Natural immunity was estimated to be about 13 times stronger than having two doses of the Pfizer-BioNTech vaccine.
www.news-medical.net
The key being:
"vaccines can add an extra boost to protection in people who recovered from COVID-19. Results showed that a single vaccine dose with natural immunity provided greater protection against reinfection than people with natural immunity alone."
The above was from the study in Israel that looked at:
"three groups in the study: 673,676 individuals who were fully vaccinated with the Pfizer-BioNTech vaccine and with no prior exposure to SARS-CoV-2; 62,883 unvaccinated individuals who recovered from COVID-19; and 42,099 individuals with prior SARS-CoV-2 infection and who had received a single vaccine dose."
Our CMO (chief medical officer) uses an analogy for explaining this that I think people can understand well. It isn't his analogy, but plagiarism is the highest form of flattery. It is called the swiss cheese model. Think of taking random slices of swiss cheese and stacking them. When you do this, often, the holes in the cheese will line up. When they do, you have a gap in your protection. This works all the way through the stack of things we do to protect ourselves from a virus like this. So all of the following things help:
- Masks
- distancing
- One vaccine does
- Two vaccine doses
- A booster dose
- prior covid infection
- quarantine
- hand washing
- avoiding touch your face
- eye protection
- full PPE (personal protective gear)
- etc
So think of each of these as a slice of cheese. If you stack all of these slices, what is the chance you can drop a pea on top and have it pass to the very bottom? Obviously not very likely...but not impossible. But the more slices you employ, the better the chance is that you'll stop that pea from passing through. Then think about each of those slices - a vaccine slice has very few holes in it. A cheap mask has lots more holes, an N95 has far fewer etc etc. I think the analogy is one most people can wrap their heads around.