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The Latest: Time to upgrade your mask

Dear Reader,

Some good news:

  • U.S. will have enough doses to vaccinate 300 million Americans: President Joe Biden will purchase another 200 million doses of Pfizer-BioNTech and Moderna’s Covid-19 vaccines, which will give the U.S. enough to fully vaccinate Americans by the end of this summer, the White House says.
  • Regeneron’s antibody cocktail prevents Covid-19 infection, data shows: The company shared that REGEN-COV caused a 100% reduction in symptomatic infection and roughly 50% lower overall rates of infection in around 400 people in a trial. Read more.
  • Moderna says its vaccine protects against variants: The company announced on Monday that the vaccine is effective against the new coronavirus variants that have emerged in Britain and South Africa, although it looks like it may be less effective against the latter. The company is now developing a new form of the vaccine that could be used as a booster shot against that strain.

A quick Q&A: If I am vaccinated, do I still need to wear a mask?

Yes, you do. But not forever. As my colleague Yasmin Tayag reports, people will still need to wear masks as the nation works to achieve herd immunity. There are a couple reasons for that. One, it takes time for a vaccine to become fully effective in the body, and with Covid-19 spreading widely, it’s important to still try to avoid getting infected during that immunity-building period. Second, it’s still not yet known for certain if the vaccines definitely prevent people from spreading Covid-19, even if they prevent people from getting sick from it. So while there are still large groups of unvaccinated people, wearing masks will continue to be a tool to help end the pandemic. “The promising news is that this won’t have to last forever — as more people get vaccinated, vaccine-induced herd immunity will eventually be reached,” Yasmin writes.

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Health and science journalist. Former editor of Medium’s Covid-19 Blog and deputy editor at Elemental. TIME Magazine writer before that