COVID-19 Vaccination Effort Could Be Double Dose of Complication

Imagine all the logistics that go into inoculating more than 300 million Americans with a COVID-19 vaccine.

Think about the number of syringes needed. The number of needles. The vials of vaccine. Even the number of Band-Aids needed after the shots.

Now, double it all.

That's because it's looking more likely that people will need two doses of the vaccines being developed to fight off the new coronavirus.

Meanwhile, an advisory panel on Tuesday recommended how to ration the initial, limited doses of whichever vaccine wins approval first.

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Nearly 184,000 people have died because of COVID-19 in the United States, according to data compiled by Johns Hopkins University. More than 6 million infections have been confirmed in the U.S. Globally, the new coronavirus has killed more than 850,000 people and infected 25.6 million.

"There's no question that this is going to be the most complicated, largest vaccination program in human history, and that's going to take a level of effort, a level of sophistication, that we've never tried before," Kelly Moore, the associate director for immunization education with the Immunization Action Coalition, told CNN.

Six companies are participating in the federal government's Operation Warp Speed program to create and distribute 300 million doses of a safe, effective vaccine for COVID-19 by January 2021.

Two of the companies, Pfizer and Moderna, are in Phase 3 clinical trials in which 30,000 volunteers in each trial will get two doses of the vaccine candidates or two doses of a placebo, according to a report by Fox News.

AstraZeneca announced Monday its vaccine candidate has entered Phase 3 testing in the U.S. and participants in it will also receive two doses. Johnson & Johnson also is considering giving some participants in its upcoming Phase 3 trials a double dose.

"The process of vaccination is literally teaching your immune system to recognize and react to a dangerous virus when it sees the virus. The first dose triggers important immune system changes, sometimes called 'priming' the immune response, and this process takes about two or three weeks. The second dose boosts that first immune response and the boosting process take about two weeks," Moore explained to Fox News.

Many vaccines require more than one dose. For example, the childhood vaccine for chickenpox requires two doses, as does the adult vaccine for shingles.

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When a coronavirus vaccine is eventually approved, a big question will be who gets it first. The first supplies are expected to be enough for about 15 million people, according to the Associated Press.

In a draft proposal Tuesday, the National Academies of Sciences, Engineering and Medicine recommended those first doses go to high-risk health care workers and first responders.

Next in line would be older residents of nursing homes and other crowded facilities and people with underlying health conditions that put them at higher risk.

The next phase would add workers in essential industries who are at high risk of contracting COVID-19 and teachers and school staff, among others. Other groups would be added as the phases progress.

The National Academies are seeking public comments on the plan through Friday.