What a vaccine is really meant to do is prevent disease. So, it doesn't stop you from getting the virus, but it can keep you from getting a disease, kind of like a burglar showing up to your house.
Unlike any other living thing, viruses make more of themselves through something else. A virus needs to duplicate itself to survive, and to do that it needs access to living cells, such as in humans. However, if it tries to infect an individual and finds it can’t replicate because that person has immunity, that virus tries to find someone else. If the virus keeps encountering people with immunity, that virus’ biological clock will eventually run out and die off. Herd immunity means enough people have immunity where the virus can't spread. However, herd immunity is not the sole target of a vaccine.
Going back to our analogy, if one house has a security alarm and no other homes in the neighborhood do, burglars are still going to show up to that neighborhood. However, if everyone in that neighborhood has a security system that burglar has nowhere to go, so burglars will stop showing up there. That's the purpose of the vaccine and if enough people have it, it just won't bother with humans anymore, it will die out.
Understanding the Herd Immunity Threshold
We don't know yet know what the COVID-19 herd threshold is and it's not something that we can easily guess. The way to definitively determine the threshold is to vaccinate as close 100% and see when the cases begin to drop significantly. Then you decrease the rates of vaccination and see if the cases rise again. That's how we feel comfortable knowing measles herd immunity is around 90%, because in areas where less than 90% of people are vaccinated, we see outbreaks of measles. But for COVID-19, no one knows the right number yet. There's still a lot of face masking in public, and social distancing is still happening so the combination of the two is probably what's working and if we relax one, we may see those numbers spike again.
So, though we shouldn’t be obsessed with hitting herd immunity, I think we should be obsessed with getting as many people to immunity as possible because we know that it protects people from dying from COVID-19. To date, there have been zero reported deaths of 95 million people who have been vaccinated. Meaning, all of the deaths that are happening right now are from unvaccinated people. The goal really should be preventing disease, that will achieve the concept of herd immunity.
Loosening Mask Mandates
We are still learning about virus transmission and early data shows that vaccines help keep fully vaccinated people with no symptoms from spreading COVID-19. My recommendation is if you're going out in public, like to the store, still wear a face mask. Just until we have a better understanding of the biological spread of this virus and more people who have been vaccinated. However, if you're with people and everyone around you has been vaccinated, I think you party like it's 1999.
Though the ability to stop wearing a mask is a good incentive, we have no way to monitor vaccination status. We need to continue to see the vaccination numbers go up and the number of COVID-19 cases go down. The new CDC rules allow people who've gotten vaccinated to go out without face masks in certain circumstances but if non-vaccinated people begin to do that, then we will still see the cases go high.
So, we don't want to let our guard down. If you want to hang out with people, talk to them like you did before the pandemic. Ask “what have you been doing to prevent catching the virus? What is your vaccine status?” I strongly urge that, and I would still follow CDC regulations.
Talk to Your Doctor
As a doctor, I treat every patient individually. I can sit down and talk about the vaccines for about 8 hours, but no one wants to hear that. I try to lay out the facts that they need to take make the decision for themselves. So, when I sit down with them, I say we know the vaccine can end this pandemic, tell me what your concerns are? Someone may be worried about it being rushed, so we go over that. Others may ask about spreading the virus after vaccination or about the vaccination creation, all things that can be addressed if you just ask. So, I would always suggest telling your physician what your concern is and then together you can address it.
Blog last updated: May 29, 2021