Will one dose of a two-dose COVID-19 vaccine protect me?

One dose of a two-dose COVID-19 vaccine will provide some protection, but not nearly as much as if you had both doses

LONDON -- Will one dose of a two-dose COVID-19 vaccine protect me?

With the delta variant, a study by British researchers found people were well protected when they got both doses of either the AstraZeneca or Pfizer-BioNTech vaccines. But with only one dose, protection was significantly reduced.

Health officials are also concerned about the dozens of countries that still don't have enough supply secured to distribute second doses within the recommended time frame.

World Health Organization chief Tedros Adhanom Ghebreyesus has said vaccinations with only one dose won’t be enough to stop outbreaks fueled by new variants and that people should maintain social distancing and other measures until more of the population is fully vaccinated.

The second dose of a two-dose vaccine is critical because it's what “really gives a boost to the immune system so that the antibody response is very strong,” says Dr. Soumya Swaminathan, WHO's chief scientist.

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