Public health experts for months have been sounding alarms of a "nightmare" that could occur if the United States sees its traditional flu season mixed with high rates of coronavirus transmission. Now, to ward off the nightmare scenario, officials have a clear message for the public: Get your flu shot.

The 2019-2020 flu season, charted

Two potential scenarios for this flu season

The United States could face one of two very different scenarios unfold this flu season: One in which the country faces a relatively mild flu season compared to recent years, in part due to physical distancing and other measures put in place to reduce the novel coronavirus' transmission; and another in which a severe flu seasons combines with America's persistently high rates of coronavirus transmission to overwhelm the country's health care system.

On one hand, Thomas LaVeist, dean of the school of public health and tropical medicine at Tulane University, said measures put in place to "help reduce the spread of [the coronavirus] are the same measures that would help reduce the spread of influenza."

In addition, according to Eric Percher, a senior analyst at Nephron Research, researchers have projected that 20% more Americans will get vaccinated against the flu this year when compared with previous years.

But on the other hand, if the United States experiences a flu season more in line with what it's seen in recent years, both flu cases and cases of Covid-19, the disease caused by the novel coronavirus, could surge and overwhelm hospitals.

"It could be daunting … because flu is going to be competing for the same resources as the coronavirus in terms of hospital beds, ICU beds, ventilators, personal protective equipment, and even the reagents for diagnostics testing," Amesh Adalja, senior scholar at Johns Hopkins Center for Health Security, said.

And Lawrence Gostin, a global health professor at Georgetown University, explained that the United States could have the ideal conditions for such a scenario to occur.

"You've got this perfect storm in autumn. Everyone is back from vacation. Some are going back to work. In some parts of the country, schools are starting," Gostin said. "You have a mass migration, and with it people are going to be bringing both influenza and Covid-19. … To me, there is no plausible reason why we wouldn't have both."

Another worry is the potential for people to get infected with both flu and Covid-19. "We don't really know what would happen if you are dually infected," LaVeist said.

Many experts also are concerned that, without better testing for the pathogens, people may not know whether they have the flu or Covid-19, which require different treatments—and different responses.

"Basically, employers, school systems, and others are going to have to make a decision. Will we just assume that if we see a surge in influenza-like illnesses, we're going to behave as if it's Covid-19?" Julie Fischer, senior technical adviser for global health at CRDF Global, said. She added, "Once we hit cold and flu season, when some of the very general symptoms associated with Covid-19 like fever and cough become more common, then it's going to be a very complex problem in the areas where testing is still being controlled based on symptoms and exposure risks."

How officials are trying to prevent the 'nightmare' scenario

To ward off the potential nightmare scenario, health care officials and industry stakeholders are pushing one clear message to Americans: Get your flu shot.

"This is a critical year for us to try to take flu as much off the table as we can," CDC Director Robert Redfield has said, warning that, otherwise, "[o]ur hospital capacity could get strained."

To help, flu vaccine manufacturers have ramped up production of this year's vaccine by about 15% when compared with previous years, the Washington Post reports.

CDC also has announced that a high-dose flu shot aimed specifically at protecting people ages 65 and older will protect against four strains of the flu this year, up from the vaccine's typical protection against three strains of influenza. The agency also is purchasing an additional 9.3 million doses of the adult influenza vaccine and an additional two million doses of the pediatric influenza vaccine this year when compared with previous years, Axios reports.

In a Morbidity and Mortality Weekly Report published Friday, CDC emphasized the importance of getting a flu shot this year, stating, "[p]revention of and reduction in the severity of influenza illness and reduction of outpatient illnesses, hospitalizations, and [ICU] admissions through influenza vaccination also could alleviate stress on the U.S. health care system."

In addition, CDC is strongly recommending that Americans ages 65 and older, as well as smokers ages 19 to 64, this year receive a vaccination that can protect against certain types of pneumonia.

Further, HHS Secretary Alex Azar last week issued a directive that will allow pharmacists in all 50 states to administer childhood vaccinations this fall, including flu shots, without needing a prescription from a physician. Azar said he issued the directive to help expand access to the vaccinations and prevent outbreaks of other preventable diseases amid America's coronavirus epidemic.

For their part, doctors say Americans shouldn't delay getting vaccinated against the flu, and the American Academy of Pediatrics has noted that children who receive the shot in September or October should be protected for the remainder of flu season.

It is "better to get [your flu shot] when you are thinking about it, otherwise you might wait too long or forget," Mark Sawyer, a pediatric infectious disease specialist at Rady Children's Hospital-San Diego and a professor at the University of California-San Diego, said. Sawyer also advised that, if your child receives a flu vaccination from a pharmacist, you should keep a record of when your child received it—particularly if they'll need to receive a second dose later.

And some states even are requiring certain people to get vaccinated against the flu this season. For instance, Massachusetts last week announced that it will require all students in the state—including children ages six months and older in child care centers and all other students up to age 30—to be vaccinated against the flu by Dec. 31. The requirements also apply to young students currently enrolled in remote learning, though it allows for exceptions for all students based on religious and medical reasons, students who are home-schooled full time, and students in colleges and universities who are enrolled in remote learning and do not visit campuses in person (Caron, New York Times, 8/25; O'Reilly, Axios, 8/20; Hoffman, New York Times, 8/20; Brown, Medscape, 8/21; Sun, Washington Post, 8/20; King, FierceHealthcare, 8/20; Stobbe, Associated Press, 8/19).