Britain’s National Health Service began delivering shots of the Pfizer-BioNTech vaccine on Tuesday, opening a public health campaign with little precedent in modern medicine and making Britons the first people in the world to receive an authorized, fully tested vaccine.

Here’s a guide to some of the basics.

Should I be concerned about the safety of the vaccine in Britain?

Continue reading “U.K. Coronavirus Vaccine: Side Effects, Safety, and Who Gets It First” →

Across the world, mass vaccination campaigns are beginning, or just about to.

Russia began its campaign on Saturday. Britain will start its campaign on Tuesday. The United States hopes to start large-scale vaccinations this month, as does Turkey. Hundreds of thousands of people have already been vaccinated in China, and thousands in the United Arab Emirates and elsewhere.

But the mass vaccination efforts differ in one profound way: Some rely on a vaccine that has completed human trials — and some do not.

Continue reading “Mass vaccinations are beginning. They’re not all the same.” →

A new study in monkeys suggests that a blood test could predict the effectiveness of a Covid-19 vaccine — and perhaps speed up the clinical trials needed to get a working vaccine to billions of people around the world.

The study, published on Friday in Nature, reveals telltale blood markers that predict whether a monkey’s immune system is prepared to wipe out incoming coronaviruses.

The finding raises hope that researchers will be able to look for the same markers in people who get vaccines in clinical trials. If the markers are strong enough, they could reveal if the vaccines protect against Covid-19. And researchers would no longer have to wait for some trial volunteers to get the disease, as they do now.

Continue reading “Could a Blood Test Show if a Covid-19 Vaccine Works?” →

In October, Judith Munz and her husband, Scott Petersen, volunteered for a coronavirus vaccine trial. At a clinic near their home in Phoenix, each got a jab in the arm.

Dr. Petersen, a retired physician, became a little fatigued after his shot, and developed redness and swelling on his arm. But Ms. Munz, a social worker, didn’t notice any change. “As much as I wanted it, I couldn’t find a darned thing,” she said. “It was a nothing burger.”

Continue reading “Many Trial Volunteers Got Placebo Vaccines. Do They Now Deserve the Real Ones?” →