'A little bit of hope': COVID-curbing efforts may mean milder flu season

Experts have been raising the alarm about the coming flu season, warning that the combination of the seasonal virus plus COVID-19 could overwhelm the nation's health care system. But global efforts to curb the spread of the coronavirus may mean the U.S. is in for a milder flu season.

Indeed, it appears efforts to curtail the coronavirus have led to significantly fewer cases of influenza in the Southern Hemisphere, currently in the midst of its winter months, which is typically a precursor to the U.S.'s flu season.

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"If we look at what they've been seeing in Australia, and we use the Southern Hemisphere to predict what our next season is going to be, they've had a quieter flu season," Dr. Kristin Englund, an infectious diseases expert at the Cleveland Clinic, said. "We think that's because people have been using measures to prevent COVID-19."

Dr. Christopher Ohl, a professor of infectious diseases at Wake Forest Baptist Health in Winston-Salem, North Carolina, agreed that "there is a little bit of hope that the flu season will a little less severe this year."

If infection control measures — including travel restrictions, hand-washing, physical distancing and mask wearing — work for COVID-19, Ohl said, they're "going to work for flu, too."

That said, there are plenty of reasons experts remain concerned about the upcoming flu season. Unlike the coronavirus that hasn't shown seasonal patterns, influenza is sure to make a comeback as the weather turns colder. And it can have devastating effects on the nation's health care system, filling both emergency rooms and intensive care units.

The Centers for Disease Control and Prevention estimated that during the 2019-20 season, there were as many as 56 million flu illnesses in the U.S., resulting in up to 740,000 hospitalizations.

Coupled with COVID-19, the flu will "put significant strain on how many people are in emergency department, how many people are admitted to a hospital, how many people need a ventilator," said Dr. Marybeth Sexton, an assistant professor of infectious diseases at the Emory University School of Medicine in Atlanta.

"We really need to prevent having both of those illnesses hit at the same time."

One way to lower the risk of flu is to get a flu shot, and indeed, many pharmacies are already advertising flu vaccines for the upcoming season. Last week, Dr. Brett Giroir, who oversees coronavirus testing for the Trump administration, told NBC News that the federal government has ordered extra flu shots this year.

Some infectious disease experts maintain, however, that August is too early for most people to get the shot.

"We're recommending people wait until September or October," Englund said. "If people get the flu vaccine now, protection may not extend throughout the entire flu season."

Still, expect a major public health push for flu vaccines within the next few months, even though it does not prevent a majority of influenza illnesses. Studies have shown the vaccine can help lessen the severity of the flu.

"We're all scrambling and frantic to try and get a COVID-19 vaccine. Why not use the vaccine that we currently have available to protect ourselves?" Englund said.

Complicating matters for physicians is that symptoms of the flu and COVID-19 can overlap: fever, cough, shortness of breath, fatigue, body aches.

"It's very hard to tell them apart," Sexton said. "And they have different incubation periods, different recommendations about when it's safe to return to work or normal activity after you have them."

The coronavirus "is proving exceptionally difficult to stop. It's difficult to recognize; it's difficult to distinguish between it and other syndromes unless you have adequate and immediate testing," Dr. Mike Ryan, executive director of the World Health Organization's health emergencies program, said during a news conference Monday.

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That means quick and accurate testing for both flu and COVID-19 will be critical this fall. According to Giroir, point-of-care tests for the coronavirus, like rapid flu or strep tests, should be readily accessible within the coming months.

He added that he anticipates such tests would be administered in conjunction with flu tests, using the same samples.

Englund was not as optimistic. "What may happen is that you get ruled out in the doctor's office for influenza, and are told the sample will then be sent off for COVID testing," she said.

In addition to getting a flu vaccine within the next few months, Ohl said there are several things people can do now to slow the spread of all respiratory viruses: wear a mask, wash your hands and avoid large gatherings.

"If we do all of those things," Ohl said, "we can hopefully dampen down COVID, the flu and all of those other nasty cold viruses that you can get this time of year."

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