THE UNITED STATES is in an “unnecessary predicament” of soaring Covid-19 cases fuelled by unvaccinated Americans and the virulent Delta variant, the nation’s top infectious diseases expert has said.

“We’re going in the wrong direction,” said Dr Anthony Fauci, describing himself as “very frustrated”.

He said recommending that the vaccinated wear masks is “under active consideration” by the government’s leading public health officials.

Also, booster shots may be suggested for people with suppressed immune systems who have been vaccinated.

Fauci, who also serves as US President Joe Biden’s chief medical adviser, told CNN’s State Of The Union that he has taken part in conversations about altering the mask guidelines.

He noted that some local jurisdictions where infection rates are surging, such as Los Angeles County, are already calling on individuals to wear masks in public regardless of vaccination status.

Dr Fauci said those local rules are compatible with the Centres for Disease Control and Prevention recommendation that the vaccinated do not need to wear masks in public.

Nearly 163 million people, or 49% of the eligible US population, are vaccinated, according to CDC data.

Dr. Anthony Fauci says US is "going in the wrong direction" as the number of Covid-19 cases continues to rise, particularly among unvaccinated Americans. https://t.co/BtMUrX2WfD #CNNSOTU pic.twitter.com/QxPOQ3d2J3

— State of the Union (@CNNSotu) July 25, 2021

“This is an issue predominantly among the unvaccinated, which is the reason why we’re out there, practically pleading with the unvaccinated people to go out and get vaccinated,” Dr Fauci said.

He said government experts are reviewing early data as they consider whether to recommend that vaccinated individuals get booster shots.

He suggested that some of the most vulnerable, such as organ transplant and cancer patients, are “likely” to be recommended for booster shots.

He also praised Republicans, including governors Asa Hutchinson of Arkansas and Ron DeSantis of Florida, and the second-ranking House leader, Steve Scalise of Louisiana, for encouraging their constituents to get vaccinated.

Their states have among the lowest vaccination rates in the country.

“What I would really like to see is more and more of the leaders in those areas that are not vaccinating to get out and speak out and encourage people to get vaccinated,” Dr Fauci said.