Q&A: The road to herd immunity

We’ve been hearing about herd immunity for months now, haven’t we? But, what does it really mean, and why is it important? Jim Whitfill, MD, senior vice president and chief transformation officer at HonorHealth, helps answer some common questions about herd immunity, and how it will help in the fight against COVID-19.

Q: What is herd immunity?

A: Herd immunity means that enough people in a community are protected from getting a disease because they've either already had the disease and developed antibodies, or because they've been vaccinated. Remember, for the Pfizer and Moderna vaccines, the first dose is only 50% protective after 10 days of receiving your shot. You need to come in for your second vaccine dose 21-30 days after your first, and then wait two weeks, in order to achieve 94-95% protection.

Q: Why does it matter?

A: Herd immunity essentially makes it harder for a disease like COVID-19 to spread from person to person. It even protects those who can't be vaccinated, like newborns or those who are allergic to the vaccines. It's critical that we reach herd immunity, so we can bring an end to the current pandemic.

Q: Won't variants make herd immunity harder to reach?

A: While it's true that we've seen a number of variants spreading around the globe, it's worth noting that viruses can't mutate if they aren't spreading or replicating. If we can get people vaccinated as quickly as possible, we can limit the spread of COVID-19 and prevent the further emergence of variants.

Q: What's the tipping point to reach herd immunity?

A: The percentage of people who need to have protection in order to achieve herd immunity varies by disease. We're still learning how many people need to be vaccinated against COVID-19 before most people can be considered protected, but, in Arizona, we're projecting this number to be around 75% of the population.

Q: Why should I get the vaccine?

A: We've seen COVID-19 vaccines bring new hope to our frontline workers and the community. Although we've made great progress, we've still got a ways to go to reach herd immunity through immunization. We understand the choice to get vaccinated is a personal decision, but we urge each of you to consider getting the vaccine as soon as possible. Every person who receives the vaccine brings us one step closer to herd immunity. While it's true we don't yet know if COVID-19 will ever entirely go away, having a large number of the population vaccinated will save lives, reduce transmission and help control the current pandemic.

Q: I already have antibodies because I've had COVID-19. Do I still need to get vaccinated?

A: We continue to see that vaccination after having had COVID-19 is more protective than relying just on the immunity we get after infection. This may be due to some of the variants that are circulating, but it further underscores how effective the vaccines have been against this virus and how instrumental they will be toward achieving herd immunity.

Q: Do the benefits of the vaccines outweigh the risks?

A: COVID-19 has been a frightening experience for many. Some are also worried about the vaccines. While the very rare blood clots seen in some vaccines, including the Johnson & Johnson vaccine here in the United States and the AstraZeneca vaccine overseas, have gotten a lot of media attention, it's important to keep in mind that the risk of COVID-19 is much greater than these one in a million risks of blood clots, or the other mild side effects seen in the mRNA vaccines. Learn more about potential side effects.

Q: Should I get the vaccine if I'm pregnant or plan to become pregnant soon?

A: We know there are a number of younger women who have concerns about the vaccine with regards to fertility and pregnancy. As we learn more about the risk of COVID-19 and pregnancy, it's becoming clear that COVID-19 infection poses a serious risk to pregnant women. At the same time, we continue to gather more data that vaccines are very safe – even in pregnant women. The CDC now recommends pregnant women get vaccinated to reduce the risk of severe illness for themselves and their baby. If you're trying to get pregnant now or hope to get pregnant in the future, you also may still get vaccinated. There is currently no evidence the vaccines cause fertility problems. You also do not need to avoid pregnancy after receiving a COVID-19 vaccine. Like all vaccines, scientists are studying COVID-19 vaccines for side effects and will report additional data as it becomes available.

Q: When will things get back to normal?

A: We're all ready for this pandemic to be over, so we can get back to doing the things we love and seeing our friends and family like we did before. While there are a couple of ways to get there, getting as many people vaccinated as possible is the fastest, safest and economically most viable way to getting back to normal. We can't predict exactly when we'll reach herd immunity, but we know we're getting closer. We ask that you remain patient and continue following CDC guidelines in public, even if you've been vaccinated. Don't give up now when we've made it this far. Let's get through this together.



Next steps

The choice is yours to make. If you have additional questions before you make a decision, please talk to your healthcare provider.

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