The Biden administration suggests Americans get a third dose of the COVID-19 vaccine eight months after their last jab.

The booster shots should be available to U.S. citizens as soon as September or mid-September while waiting for the U.S. Food and Drug Administration’s (FDA)’s approval, Reuters reported.

The booster shot will be administered to citizens after the initial round of two shots of mRNA vaccines or the one-shot Janssen. The administration also recommended the shots should not be more than eight months apart.

The Biden administration is expected to make its official announcement this week. The New York Times said the first recipients of the booster shots are most likely nursing home residents, health care staff, and older people.

The third shots of the COVID-19 vaccines from Pfizer and Moderna manufacturers were authorized last week for those with compromised immune systems, making them much more vulnerable to the lethal virus than others. 

Previously, it was believed that two doses would be adequate to consider a person shielded. However, reports from other countries show that the shots’ protection could indeed fade out in less than a year, in line with Pfizer’s claim last month. 

In July, Pfizer said their vaccines’ effectiveness could fade out six months after the first round of doses.

More breakthrough cases in the country are emerging. Still, most reports said the patients were asymptomatic and less likely to be hospitalized or even die from the virus. That information is prompting authorities to push unimmunized Americans to get the shots.

The Associated Press said U.S. health officials did not initially consider the need for the third dose of the vaccines. Still, they changed their stance purportedly after the surge of the Delta variant, which is now raging worldwide even to countries known for their successful record of defending against COVID-19 spread.

The White House gave reassurance that the United States has enough domestic supply for the booster shots even after it had donated more than 110 million vaccine doses to other countries.

Critics such as the World Health Organization (WHO) said richer countries should hold back on administering the third dose of COVID-19 vaccines due to inadequate vaccine supply in poorer countries.

Israel had already started to administer fully vaccinated over 60 elders more than five months ago when it tried to control the fast-spreading Delta variant.