Rob Stein

Johnson & Johnson says a booster six months after the first shot increases antibodies 12-fold, indicating a second shot would provide added protection.

But the researchers stressed that all three vaccines, including the Pfizer and Johnson & Johnson shots, provide strong protection against people getting so sick that they end up in the hospital.

As the delta surge continues, there are signs it may be slowing in hard-hit states like Florida and Texas. But with fall coming, experts worry another surge could hit northern states.

As the delta variant causes more vaccinated people to get "breakthrough infections," concerns are rising that even the vaccinated could develop long COVID symptoms in rare cases.

The Biden administration plans to unveil another strategy to fight the latest COVID-19 surge driven by the delta variant, after a series of setbacks and missteps in the battle against the pandemic.

Demand for COVID-19 testing is surging, and that includes rapid home antigen tests. Experts say these tests can be very useful, but it's important to know their limitations.

The company said that when study participants were given a second jab after six months, their antibody levels were nine times higher than they were 28 days after a first dose of the COVID-19 vaccine.

Johnson & Johnson said that when it gave study participants a second jab after six months, their antibody levels were nine times higher than they were 28 days after a first dose of the COVID vaccine.

The Food and Drug Administration has given full approval to Pfizer's COVID-19 vaccine, offering the nation's vaccination campaign a badly needed boost.

FDA gives full approval to Pfizer's COVID-19 vaccine, a highly anticipated move that could give the nation's vaccination campaign a badly needed boost.

The latest coronavirus surge is ratcheting up fears about the toll, and intensifying pressure to get more people vaccinated, wearing masks and perhaps start offering booster shots.

The CDC information dated Thursday gives new details on this variant of the coronavirus and says the agency should "acknowledge that the war has changed." It was first reported by The Washington Post.

A small Israeli study of vaccinated health care workers found that a handful who got infected developed headaches, muscle pain, fatigue and other symptoms of long COVID that lasted for weeks.

For the first time, scientists have shown that a new kind of genetic engineering can crash populations of malaria-spreading mosquitoes.

With the Delta variant fueling a new surge in the U.S., a growing chorus of pubic health experts are calling for everyone to mask back up, especially indoors, and to use good masks that fit.

New estimates show the U.S. is on track to see a big rise in cases and more than triple the number of deaths by October.

The latest COVID-19 surge is on track to worsen this summer, causing a significant increase in the number of hospitalizations and deaths, according to new research from advisers to the CDC.

Fully vaccinated Olympic athletes and members of Congress have tested positive for the virus. Should you be worried? How common are breakthrough infections, and are they rising?

As the delta variant takes over in the U.S., new, localized outbreaks are emerging. Those surges are likely driven by pockets of dangerously low vaccination rates.

The CDC released new estimates showing the highly contagious delta variant now accounts for more than 51% of cases in the U.S. In some parts of the country, the strain is responsible for 80% of cases.