The US Centers for Disease Control and Prevention is advising pregnant women to get a new flu shot.
The vaccine is designed to prevent the virus from reaching babies.
The shots are only available at pharmacies and other healthcare facilities that have pharmacy pharmacies.
The US has had a record-high number of coronavirus cases this year and more than 3,400 have died.
In some states, people with a history of taking the flu shot may also be vulnerable to contracting the virus.
The shot, which costs about $160, is available for free through a health insurance plan.
There are currently 2.7 million doses of the vaccine.
The government has not yet issued an official guidance on how many people should receive the shot.
It is the latest in a series of measures taken by the US health and human services to fight the coronaviruses pandemic, which began last year and killed nearly 9,000 people.
Some of those who have died include an American man who died in the US, an Australian woman who died from the virus in Sydney and an American doctor in California who was diagnosed with the disease.
More than 40,000 US troops and their families were also vaccinated.
There have been more than 2,600 deaths, and more Americans have died from coronaviral infections in the past two years than in all of last year.
The UK, France, Germany, Spain and Sweden have all banned or delayed the use of the flu vaccine, although Britain has announced a temporary stop to the shot and France has said it will reintroduce it for another six weeks.