The flu is a far bigger threat to most people in the US than the Wuhan coronavirus. Here's why.

The virus has spread to nine other countries, including the US.
Patients experience fevers, headaches, and pneumonialike symptoms .
But according to health experts and the CDC, the flu is a far graver health threat in the US than the Wuhan coronavirus.
Since October, up to 20,000 Americans have died of the flu. During the severe 2018 flu season, 80,000 people in the US died.
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On Friday morning, the Centers for Disease Control and Prevention (CDC) announced that a second person in the US had been diagnosed with the Wuhan coronavirus.

The woman traveled to Wuhan, China, at the end of December and returned to Chicago on January 13. The announcement of her diagnosis came three days after a man in Washington state contracted the virus . Public-health officials in the US are monitoring at least 63 additional patients from 22 states.

Although the CDC considers this coronavirus (whose scientific name is 2019-nCoV) to be a serious public-health concern, the agency said in a statement Friday that "the immediate health risk from 2019-nCoV to the general American public is considered low at this time."

A graver health risk for Americans not just right now, but every year is the flu.

Since October, up to 20,000 people in the US have died of influenza. The coronavirus, meanwhile, has infected about 914 people worldwide and killed 26.

"When we think about the relative danger of this new coronavirus and influenza, there's just no comparison," William Schaffner, a vaccine expert at Vanderbilt University Medical Center, told Kaiser Health News (KHN) . "Coronavirus will be a blip on the horizon in comparison. The risk is trivial."

Flu season Ted S. Warren/AP Photo

Tens of thousands of Americans die of flu every year

At least 15 million Americans have caught the flu in the last four months; nearly a quarter million of them went to the hospital. Since flu season peaks between December and February , so the worst could be still to come.

"Influenza rarely gets this sort of attention, even though it kills more Americans each year than any other virus," Peter Hotez, a virologist at Baylor College of Medicine, told KHN.

In 2018, which brought the worst flu season in about 40 years, 80,000 people in the US died of the illness .

flu patient Scott Olson/Getty

The flu is not just a US problem, of course. According to the World Health Organization, seasonal influenza viruses infects between 3 million and 5 million people worldwide annually, and kills up to 650,000 per year.

Comparing the flu and the Wuhan coronavirus

Both the flu and the coronavirus can be transmitted from person to person via coughing and other close contact.

wuhan virus symptoms Samantha Lee/Business Insider

So far, experts report that the median age of those who have died from the Wuhan coronavirus is around 75. Many of these individuals had other health issues like high blood pressure, diabetes, and Parkinson's disease.

According to Adrian Hyzler, chief medical officer at Healix International, children, elderly people, pregnant women, and those who are immuno-compromised are more susceptible to the Wuhan coronavirus' severest complications.

"The people who are likely to die at first will be people who have other illnesses," he told Business Insider. "But as it spreads, it'll pick up more people like flu does people in their 30s, 40s, who are otherwise good and well but unfortunately get ill," Hyzler's added. His firm offers risk-management solutions for global travelers.

Health Officials in hazmat suits wait at the gate to check body temperatures of passengers arriving from the city of Wuhan Wednesday, Jan. 22, 2020, at the airport in Beijing, China. Nearly two decades after the disastrously-handled SARS epidemic, China's more-open response to a new virus signals its growing confidence and a greater awareness of the pitfalls of censorship, even while the government is as authoritarian as ever. (AP Photo Emily Wang) Emily Wang/AP

The CDC, meanwhile, is far more concerned about protecting people in the US from the flu.

Between 5% and 20% of nearly 400 million Americans get the flu every year.

"It is currently flu and respiratory disease season, and CDC recommends getting vaccinated, taking everyday preventive actions to stop the spread of germs, and taking flu antivirals if prescribed," the agency said in a statement Friday.

The coronavirus doesnt have a vaccine

A key difference between the flu and the coronavirus, however, is that the former has a vaccine.

Nurse flu shot Joe Raedle/Getty Images

"Simply having the choice about whether or not to receive a flu shot can give people an illusion of control," Schaffner told KHN. (The seasonal flu vaccine is never perfect, however. It was about 29% effective last year among Americans.)

Fewer than half of US adults got a flu shot during the 2018-19 season, according to the CDC. Only 62% of children received the vaccine.

Because the Wuhan virus is new, experts have not had time to develop a vaccine.

"If Wuhan were to explode, a vaccine best-case scenario is three-quarters of a year if not longer," Vincent Munster, a virologist at the Rocky Mountain Laboratories, told Business Insider.

Several companies, including Moderna, Novavax, and Inovio, have announced preliminary vaccine development plans . But vaccine development has historically been an arduous, multi-year process (the Ebola vaccine took 20 years to make). None of the companies provided expected timelines to get their vaccines to market.

The coronavirus outbreak isnt considered a pandemic

A policeman uses a digital thermometer to take a driver's temperature at a checkpoint at a highway toll gate in Wuhan in central China's Hubei Province, Thursday, Jan. 23, 2020. China closed off a city of more than 11 million people Thursday in an unprecedented effort to try to contain a deadly new viral illness that has sickened hundreds and spread to other cities and countries amid the Lunar New Year travel rush. (Chinatopix via AP) Chinatopix/AP

China has quarantined Wuhan and 11 other cities to stop the virus' spread, though cases have been reported in nine other countries, including the US, France, and Japan.

The outbreak isn't considered a pandemic, however. The World Health Organization has so far not declared it a global public-health emergency either.

"Familiarity breeds indifference," Schaffner said. "Because it's new, it's mysterious, and comes from an exotic place, the coronavirus creates anxiety."

Aria Bendix contributed reporting for this story.