Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Photo: Justin Tallis/Pool/Getty Images

U.S. health officials have begun a clinical trial with adults fully vaccinated against COVID-19, administering a booster shot of a different vaccine brand to the one they've already received, the National Institutes of Health announced Tuesday.

Why it matters: The study will examine immune responses and the safety of mixing different vaccines. Scientists will also measure the shots' efficacy in staving off emerging variants, according to a statement from the NIH.

  • Per a statement from NIAID director Anthony Fauci: "Although the vaccines currently authorized by the U.S. Food and Drug Administration offer strong protection against COVID-19, we need to prepare for the possibility of needing booster shots to counter waning immunity and to keep pace with an evolving virus."
  • If booster shots are required, this study could help health officials decide which vaccine combinations are best.

Details: The study will examine 150 volunteers who've received one of the three COVID-19 vaccines authorized for use in the U.S. — Johnson & Johnson's, Moderna's and Pfizer-BioNTech's.

  • Each vaccine group will have enrolled some 25 people between the ages of 18 and 55 and about 25 people in the 56 years and older age group.
  • "Twelve to 20 weeks following their initial vaccination regimen, participants will receive a single booster dose of the Moderna COVID-19 vaccine as part of the trial," according to the NIH.
  • Another aspect of the study will see volunteers who've yet to receive a coronavirus vaccine enrolled. Initially, they'll receive the two-dose Moderna vaccine before receiving a booster dose of a vaccine about 12 to 20 weeks later. 

The big picture: Research indicates that all three vaccines authorized for use in the U.S. protect against variants, to varying degrees.

  • The Public Health Agency of Canada updated its coronavirus vaccine guidance on Tuesday to permit Canadians to receive a different dose for their second shot, though it still recommends using the same brand.
  • Health officials in the United Kingdom are expected to release initial results this summer of a clinical trial testing the effectiveness of mixing COVID-19 vaccines.

Go deeper: Vaccine boosters could be necessary as soon as September

Go deeper

Americans with J&J COVID vaccine left in the dark on boosters

Illustration: Brendan Lynch/Axios

Despite the White House's reassurance that boosters for Johnson & Johnson are likely on their way, J&J vaccine recipients feel left out of the conversation, the Washington Post reports.

Why it matters: The administration has said it is eyeing boosters for the mRNA shots available from Pfizer and Moderna and the FDA will meet regarding Pfizer's booster data in mid-September. (Moderna may come later.)

  • But while the White House has said it is looking at J&J boosters, the plans have not yet publicly included them.
Sep 9, 2021 - World

WHO warns Africa's COVID vaccine supply will drop by 25%

People waiting in line to register for a coronavirus vaccine in Kajiado, Kenya, on Sept. 9. Photo: Patrick Meinhardt/AFP via Getty Images

The World Health Organization warned on Thursday that Africa will receive 25% fewer doses of the coronavirus vaccine than expected by the end of the year, in part because of the approval of booster shots in developed countries.

Why it matters: The continent lags behind the rest of the world in vaccinations, and the cut to doses will further delay African countries' vaccination efforts — which raises the risk of new, more aggressive variants emerging.

Sep 8, 2021 - Health

Elderly and immunocompromised Marylanders are now eligible for COVID-19 booster shots

Maryland Governor Larry Hogan holds a news conference on the state's Covid-19 situation. Photo: Drew Angerer/Getty Images

Governor Larry Hogan (R) announced on Wednesday that elderly people who live nursing homes and people who are immunocompromised are eligible to get a COVID-19 booster shot effective immediately.

Why it matters: Maryland is the first state to announce a plan for distributing boosters to a wider population of people, outside the immunocompromised. Hogan said "confusing and contradictory" guidance from the federal government forced him to act now.