21,000 tested positive in one week after first vaccine dose: analysis

About 21,000 of the roughly 470,000 people who tested positive for COVID-19 in the U.S. in the week ending April 18 had received one dose of a coronavirus vaccine, a Washington Post analysis published on Saturday found.

As the Post reports, this is not evidence that vaccines don't work. Rather, these people contracted the virus before the effects of the vaccine could take full effect.

A study published by the Centers for Disease Control and Prevention (CDC) in March found the vaccines from Pfizer and Moderna are about 80 percent effective at preventing coronavirus infection after one dose.

Both vaccines reach their full effectiveness of 90 to 95 percent about two weeks after a second dose is administered.

Health experts have said that until vaccines fully take effect, there is little difference between vaccinated and unvaccinated individuals so it is important to still observe COVID-19 guidelines.

However, there are some benefits offered to those who become infected between doses, the Post reports.

“Even if you develop disease, you already have a head start from an immune system standpoint on controlling the virus,” C. Buddy Creech, the director of Vanderbilt University’s vaccine research program, told the Post.

“The real challenge is we have to show the blueprint to the immune system with enough lead time,” he added.

South Carolina-based infectious disease doctor Krutika Kuppalli told the Post the patients she has seen who became infected between doses mostly experienced mild symptoms of COVID-19, adding out that no medicine is 100 percent effective.

“We want this to become akin to it feeling like a nuisance cold if you get vaccinated. We don’t want people having significant morbidity and mortality from COVID,” Kuppalli said.

On Thursday, chief medical adviser to President Biden and leading infectious disease expert Anthony Fauci said that those who become infected after receiving their first dose of the vaccine may receive their second dose once they are fully recovered from the coronavirus.