COVID-19 live updates: Judge rules governor stop banning mask mandates in schools

In the midst of a delta variant surge, a new study finds that giving a booster dose of the Johnson & Johnson shot six months after primary vaccination results in a nine-fold increase of a crucial antibody response, according to a company press release.

Meanwhile, a prior study found that people vaccinated with the Johnson & Johnson vaccine still had a durable immune response at least eight months later, even without a booster.

Collectively, the findings could help inform the U.S. government's recommendations about booster shots for the 14 million people who received the single-shot Johnson & Johnson vaccine.

Boosting after six months "appears to be safe, and boosts immune responses substantially," Dr. Dan Barouch, Ph.D., director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center, told ABC News.

-ABC News' Sony Salzman

Several Paralympic athletes have tested positive for COVID-19 in Tokyo in recent days.

According to daily figures released by the Tokyo 2020 organizing committee, at least eight positive cases have been confirmed among unnamed Paralympic athletes so far, with two new cases reported on Wednesday following the opening ceremony.

The 2020 Summer Paralympics officially opened in the Japanese capital on Tuesday, after a yearlong delay due to the coronavirus pandemic. Like the 2020 Olympics, which ended on Aug. 8, this year's Paralympics is taking place under a state of emergency as Japan struggles with a growing COVID-19 crisis.

Leaders of the Orange County public school system voted Tuesday to require a mask mandate for all students and staff.

The rule goes into effect on Aug. 30 and will last for at least two months. There will be exemptions for medical reasons.

School board members cited the growing COVID-19 rates and hospitalizations in the area as the reason for their decision.

“Doctors are.

New York City Schools Chancellor Meisha Porter spoke with ABC News about the vaccine mandate for public school staff that goes into effect Sept. 27.

Porter said she was confident that teachers and other staff members would comply to ensure that classrooms are safe for everyone.

"This is the additional extra layer of protection that we didn't have a year ago," she said.

Porter said she has been in discussions with the United Federation of Teachers over what the penalties will be if a teacher doesn't comply, and she was told that "many of their members are already vaccinated."

The chancellor said those who still have concerns should know that the Food and Drug Administration has fully approved the Pfizer vaccine and it has shown to prevent severe illness.