Drugmaker Pfizer said it has started a large-scale clinical trial of a drug to ward off COVID-19 in those who are exposed to the virus.

The trial for the oral antibiotic will involve 2,660 healthy adult participants who live in the same household as someone who is infected with COVID-19.

Pfizer is also studying the drug in people who have already been infected with COVID-19 but have yet to develop serious symptoms.

"If successful, we believe this therapy could help stop the virus early, before it has had a chance to replicate extensively," Pfizer chief scientific officer Dr. Mikael Dolsten said in a statement.

The pill aims to block a key enzyme that the virus needs to replicate. If it works, scientists believe it will be effective only in the early stages of infection. Once COVID-19 becomes severe, the virus has largely stopped replicating and patients are mostly affected by an overactive immune response.

Also on Monday, U.S. President Joe Biden received a COVID-19 vaccine booster shot, days after his administration approved a third shot of Pfizer's vaccine for certain populations.

Biden told reporters at the White House before receiving his shot on camera that "boosters are important, but the most important thing we need to do is get more people vaccinated" with their initial shots.

He said 77% of the U.S. adult population has received at least one dose of a coronavirus vaccine.

The U.S. Centers for Disease Control and Prevention (CDC) approved the boosters last week for three categories of Americans: those 65 or older; front-line workers such as teachers, health care workers and others whose jobs place them at risk of contracting COVID-19; and those ages 50 to 64 with underlying conditions.

In New York

Monday is also the COVID-19 vaccination deadline for all hospital and nursing home health care workers in the state of New York. Health care staff at other facilities, including home care and hospice facilities, are required to be inoculated by October 7.

New York Governor Kathy Hochul has said she will call up medically trained National Guard members to deal with any staffing shortages that may arise if health care workers refuse to adhere to the mandatory vaccination deadlines.

Workers who refuse vaccination without a valid doctor-approved request for a medical exemption, the governor's office said, will be terminated and not be eligible to receive unemployment benefits.

Around the globe

Elsewhere, South Korea announced Monday that in October, it will begin vaccinating youngsters ages 12 to 17 and give boosters to people ages 75 and older, according to the Reuters news agency.

The booster program is prompted by a jump in COVID-19 cases following the recent Korean holiday, Chuseok, a three-day fall harvest festival. In recent weeks, people who had not been fully vaccinated accounted for more than 85% of new cases, the prime minister said, according to The New York Times.

Britain's government said Monday that Prime Minister Boris Johnson will meet on Tuesday with the COVID-19 Bereaved Families for Justice campaigning group, who have sharply criticized his handling of the coronavirus pandemic. The group said family members would tell their stories to the prime minister of how their loved ones caught the virus.

In Cuba, officials said they have begun exporting a homegrown COVID-19 vaccine, sending shipments of it to Vietnam and Venezuela. Cuban scientists have said the three-dose Abdala vaccine is more than 90% effective against COVID-19.

Jordan's royal palace said Monday that Crown Prince Al Hussein bin Abdullah II has tested positive for COVID-19 with "mild symptoms." The palace said the prince had been vaccinated.

A fourth member of the Brazilian delegation to the U.N. General Assembly also tested positive for the disease caused by the coronavirus. Pedro Guimaraes said Sunday he is fully vaccinated, asymptomatic and has been in quarantine since Wednesday.

The Johns Hopkins Coronavirus Resource Center said Monday there are currently more than 232 million COVID-19 cases globally and nearly 4.8 million deaths. More than 6 billion vaccine doses have been administered, the center said.

(Courtesy VOA:Excluding headline)

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