A new study out of Israel suggests that the first dose of the Pfizer COVID-19 vaccine is pretty effective, according to The Wall Street Journal.

What’s going on?

A new study from Sheba Medical Centre in Israel found that the first dose of the Pfizer COVID-19 vaccine is 85% effective after 15 to 28 days, The Wall Street Journal reports.

Related
Pfizer-BioNTech vaccine can defeat the COVID-19 variant found in the UK
  • The study — published in The Lancet — found the vaccine was 85% effective in stopping symptomatic COVID-19 cases.
  • However, the study found it was 75% effective against stopping asymptomatic cases, per The Hill.
  • However, the study does not determine how long the protection will last.

Why it matters

Per The Hill, the study comes as experts debate whether to delay second doses for people so that more people can get first doses of the vaccine. However, researchers worry that delaying a second dose could allow variants to spread, which could impact the overall effectiveness of vaccines.

Related
People can get infected after 1st vaccine dose and may still spread it after 2nd, doctors say
  • “Early reductions of COVID-19 rates provide support of delaying the second dose in countries facing vaccine shortages and scarce resources, so as to allow higher population coverage with a single dose,” the authors write in The Lancet, according to The Hill. “Longer follow-up to assess long-term effectiveness of a single dose is needed to inform a second dose delay policy.”

One more note

Per Reuters, a pre-published study by the Israeli Health Ministry and Pfizer found the vaccine could reduce infection for asymptomatic cases by 89.4% and symptomatic cases by 93.7%.