COVID-19 Vaccine Hesitancy and Reaching Herd Immunity

Published on: May 4, 2021fb-roundtwitter-roundemail-round
People wear face masks while walking in New York City.Getty Images

As of mid-April, all US adults are eligible to get a COVID-19 vaccine. And CDC data shows that as of May 2, more than 56% of Americans 18 and older have received at least one dose – and almost one third of the US population is fully vaccinated. Meaning: the US is closer than ever to returning to normal life.

But new data shows that vaccination rates are slowing down. In early April, more than 3.3 million Americans were getting vaccinated a day on average. By the end of the month, that number dropped to around 2.7 million. It’s a sign that vaccine supply is on its way to outpacing demand –  and research from the Kaiser Family Foundation says we could hit that point by mid-May.

Here’s why vaccination rates are slowing… 

At this point in the US’s vaccination campaign, about 70% of older Americans (think: ages 65 and up) have been fully vaccinated. And data shows that people who are most eager about getting a shot have either already gotten one or are planning to get one. Officials are now turning their efforts to groups that are less likely to be vaccinated, including younger Americans, those living in rural areas, and people who don’t have the info they need to make an informed decision or schedule an appointment (like those facing language barriers). And two obstacles they're facing are...

  • Vaccine hesitancy. Regardless of demographics like age, sex, race, or political affiliation, many Americans are dealing with vaccine hesitancy. Some people want to wait and see how others respond to the shots before getting their own – especially because some are concerned about how quickly they were developed and authorized. Others are hesitant after consuming misinformation, or not enough info, about the vaccines. (Btw, an expert from Johns Hopkins breaks down the facts here). Minority communities may also be hesitant to get a shot, rooted in mistrust in a health care system where systemic racism exists. Experts say convincing Americans who fall in these buckets to get a shot could be a challenge.

  • Accessibility. In April, President Biden said that 90% of Americans are within five miles of a vaccination site. But some people haven’t been able to get a shot because of things like scheduling conflicts (think: taking time off work), transportation limitations, or they don’t have internet access to book an appointment. In an effort to make things easier, some areas now have walk-in sites where people don’t need to make an appointment for their vaccine. And other places are offering smaller pop-up sites (including at churches or community centers) to make it easier to reach people. (You can find vaccine sites in your area here.)

Efforts are already underway to try to solve these problems. And businesses, cities, and states are offering incentives ranging from free beer and donuts to savings bonds for anyone who gets vaccinated. But this likely won’t be enough to get every single eligible American to get a shot – which officials see as a barrier to achieving herd immunity.

Here’s what you should know about herd immunity…

Herd immunity happens when a large part of a community becomes immune to a disease, making community spread less likely. While it’s been impossible to know if or when the US could reach herd immunity since the start of the pandemic, experts have predicted that anywhere between 70-90% of the population would need to be immune to hit that point. The good news is that a large chunk of the US population is already vaccinated against COVID-19. Plus an estimated 34% may reportedly have some immunity to the virus because they were exposed (and may now have antibodies to help protect them).

The not-so-good news: according to a report from The New York Times, health experts say the US may never reach herd immunity. And instead, the virus will continue to be a threat, but at a lesser level. That’ll depend on how much of the country – as well as the world – becomes vaccinated, as well as how variants continue to spread. Another potential twist in all this: we don’t know how long vaccine immunity lasts and if people will need to get an annual booster shot. But even if the US doesn’t reach herd immunity, experts say vaccinations and keeping infection rates low will still play an important role in getting closer to normalcy.


Every day, the US continues to make more progress in the fight against COVID-19. But we’re nearing a tipping point in the inoculation process – and herd immunity may not be achievable. The more we can mitigate the spread of the virus, the faster we can potentially return to pre-pandemic life.

Skimm'd by Maria Martinolich and Kamini Ramdeen

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