Washington, The US is readying for a severe flue season as well as a new wave of the Covid-19 pandemic in the upcoming fall season, with health experts urging the public to get flu shots and Covid boosters.

The US Centers for Disease Control and Prevention (CDC) is calling on everyone above six months to get their flu shots, reports Xinhua news agency.

"I don't want to be alarmist, but I am concerned. We know that it's going to be a strain of flu that tends to be more severe," said Michael Phillips, an infectious disease expert at New York University Langone Health.

"For those ages greater than 65, there's a specific formulations of vaccines that you should get and it dramatically reduces the likelihood of hospitalization and death," Phillips said.

Less than half of US adults plan to get a flu shot this year and just a third feel safe getting a flu shot and Covid-19 vaccine at the same time, according to a survey of the US National Foundation for Infectious Diseases.

Flu season typically starts in October, peaks in December through February and can last into the spring.

The CDC says the flu shot may not prevent people from getting infected, but it can significantly lower the risk of hospitalization and death.

Meanwhile, health officials are expecting another Covid resurgence as immunity from vaccination wanes off and people head indoors as the weather turns colder.

More transmissible Omicron subvariants are also emerging, and experts are urging the public to get Covid-19 vaccines and boosters to protect themselves as well as the vulnerable groups.

So far, about 67.9 per cent of the US population is fully vaccinated with their initial series, according to the latest CDC data.

But less than half of the fully vaccinated population has received a booster dose.

A new study published earlier this week by the Commonwealth Fund shows that about 90,000 Covid-19 deaths could be prevented this fall and winter if more people in the US get their booster by the end of the year.

As of Friday morning, the country's overall Covid-19 caseload and death toll stood at 98,474,755 and 1,087,350, respectively.

The two tallies account for the highest in the world, making the US the worst-hit country.