The CDC says millions of Americans aren't receiving the second dose of the coronavirus vaccine

• About 5 million Americans have so far missed their appointment to receive the second COVID-19 vaccine.
• Many Americans are reportedly choosing to miss their second dose for a variety of reasons, including a fear of potential side effects.
• Others had their second appointments canceled because vaccination sites ran out of doses.

Millions of Americans are not receiving their second dose of the COVID-19 vaccine, according to data from the Centers for Disease Control and Prevention.

The New York Times reports that nearly 8% of the people who've so far received their first dose of either the Pfizer or Moderna vaccines have missed their follow-up appointments to receive the second dose.

So far, more than 26% of the US population has been fully vaccinated against the coronavirus, according to data published by Johns Hopkins University. That figure represents about 85 million people.

There are several reasons a growing number of Americans are choosing not to receive the second dose, the Times reported. Some have said they don't want to experience any potential side effects while others feel like one dose should be enough protection against the virus.

Others are missing their second appointments because of barriers like insufficient vaccine supply at pharmacies or other vaccination sites, the Times reported.

Vaccines have been rolling out swiftly in the US since December, when Pfizer became the first company to receive approval from the Food and Drug Administration. The company expects to have delivered 300 million doses by the end of July.

Vaccinations have been staggered by groups at the recommendation of the Centers for Disease Control and Prevention. Initial vaccines were given out to front-line responders like healthcare workers and people residing in long-term facilities like nursing homes.

Then, the CDC recommended vaccine providers prioritize people over the age of 75 and give them coronavirus vaccines. Some states like New York now allow all people 16 years or older to schedule and receive a vaccine.

Last week, Dr. Anthony Fauci, the nation's top infectious diseases specialist, said he predicts all kids will be able to receive a vaccine against the coronavirus by the beginning of 2022, marking another milestone in vaccine rollout.

In order to be fully vaccinated, individuals must receive two doses of either the Pfizer or Moderna vaccine. Both have high efficacy rates, according to CDC data. CDC officials say getting both doses of either vaccine makes people up to 90% less likely to catch the virus.

Nearly 32 million Americans have been infected with the coronavirus since the start of the pandemic last year, JHU data show. Of that, more than 571,000 Americans have died from COVID-19.

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