WHAT YOU NEED TO KNOW ABOUT THE JOHNSON & JOHNSON VACCINE

Late last month, U.S. regulators authorized the use of a third coronavirus vaccine, giving the country another tool at a critical time in the pandemic.

The newest approved vaccine, made by Johnson & Johnson, requires a single shot. It’s easy to use, ship and store, and it did not cause any serious side effects during clinical trials.

“You now have three highly efficacious vaccines, for sure, there’s no doubt about that,” Anthony Fauci, the nation’s top infectious-diseases doctor, said. “I think people need to get vaccinated as quickly and as expeditiously as possible.”

With rollout starting soon, here’s what you need to know.

How is this vaccine different from the first two?

The first two vaccines authorized for use in the United States — one made by Pfizer and Biontech, the other by Moderna — require two shots, given weeks apart. The first dose offers partial protection and the second acts as a booster.

Unlike traditional vaccines, those made by Pfizer and Moderna use messenger RNA technology to train the immune system to respond to the coronavirus.

The Pfizer and Moderna doses must be kept ultracold or frozen, a requirement that has presented challenges during power outages or technology failures when health workers have scrambled to administer shots or risk the vaccines going to waste.

The Johnson & Johnson vaccine is less fussy. For starters, it’s a one-stop shot. No waiting weeks for another appointment, no logistical headaches from keeping track of who needs their second dose and who’s still waiting on their first.

The Johnson & Johnson vaccine does not use MRNA; rather, it’s what’s known as an adenovirus vector vaccine. It uses the more established approach of employing a harmless cold virus to deliver a gene that carries the blueprint for the spiky protein found on the surface of the coronavirus. The virus infects cells, which then follow the genetic instructions to construct a replica of the coronavirus spike. The immune system uses these replicas to recognize — and respond to — the real thing.

How effective is the Johnson & Johnson vaccine?

All three vaccines are “highly efficacious and quite safe,” said Philip Landrigan, an epidemiologist and the director of Boston College’s Program for Global Public Health and the Common Good.

The Johnson & Johnson vaccine completely prevented hospitalization and death, including in South Africa against a more transmissible variant, and was 85% effective at protecting against severe cases of illness.

It was 72% effective at preventing moderate illness in the U.S. trials, a number that falls short of the Pfizer and Moderna vaccines, which were about 95% effective after two doses.

When will it be available?

Initial supplies of the vaccine will be limited. However, production will ramp up, and the company says 20 million doses will be delivered by the end of this month and 100 million by the end of June.

Can I get more than one vaccine?

Current CDC guidance states the Pfizer and Moderna vaccines “are not interchangeable with each other or with other COVID-19 vaccine products.” So, no, you should not get more than one type of coronavirus vaccine.

ASSOCIATED PRESS