Covid-19 is not the flu. It’s worse.

It’s deadlier, more contagious, and more likely to severely disrupt our health care system.

 In early March, President Donald Trump tweeted a statistic he said we all should “think about.”

It was a comparison of the flu to the current coronavirus pandemic. The flu kills tens of thousands of people a year, he reminded us. At the time, only under a dozen or so people in the US had died of Covid-19, the disease caused by the novel coronavirus. The tweet read a lot like much of the rhetoric coming out of the White House, which, for weeks now, has been trying to downplay the severity of the situation.

A lot of people besides Trump have been comparing the coronavirus to flu. And it’s a question friends and family members who want to know how worried they should be keep asking me: Isn’t this like the flu?

So, a quick unambiguous answer: No, this is not like the seasonal flu. It is worse.

Put simply, while the exact death rate is not yet clear, this disease kills a larger proportion of people than the flu (and it’s particularly lethal for people older than 80).

It also has a higher potential to overwhelm our health care system and hurt people with other illnesses.

At present, there is also no vaccine to combat it, nor any approved therapeutics to slow the course of its toll on the human body. (Doctors can treat cytokine storm syndrome, an immune response that may in some cases be dealing the fatal blow to those dying of Covid-19.)

Sober-minded epidemiologists say, without exaggeration, that 20 to 60 percent of the world’s adult population could end up catching this virus.

Biologically, it behaves differently than the flu, although some symptoms are similar. It takes around five days for Covid-19 infection to develop symptoms (the most common are fever and a cough). For the flu, it’s two days. That potentially gives people more time to spread the illness asymptomatically before they know they are sick.

Around the country, health care providers are worried about their facilities being overrun with an influx of patients, and having to ration lifesaving medical supplies.

“We’re already overwhelmed here, in terms of patients coming in the middle of a terrible influenza season,” says Barbara North, the medical director of a small, rural clinic in Northern California. If the pandemic hits her community, her clinic is the only provider for miles. She fears they’d be overrun. “We are struggling to establish the isolation and infection precautions needed at the clinic.”

Three months ago, this virus was not known to science. No human immune system had seen it before January, so no unexposed human has any natural immunity to it. That means it’s more contagious than the flu — about twice as contagious, perhaps more; the numbers are still being worked out.

This is bad. It’s bad enough to roil our stock markets, put people out of work, potentially cause a recession, and infect millions, if not billions, of people around the world. It could also kill millions, both here and abroad.

It’s possible that Covid-19 will become endemic — meaning it will be a disease that regularly attacks humans and will not go away until there’s a treatment or a vaccine.

Yes, flu variants kill tens of thousands a year in the US. But imagine if there was another kind of flu, “except potentially with a higher case fatality rate,” Angela Rasmussen, a Columbia University virologist, told me recently. “Which is definitely a problem because the seasonal flu kills 30,000 to 60,000 Americans every year. And even if it’s the same case fatality rate of seasonal flu, that still presents a substantial public health burden.”

If that spooks you, now is the time to take a deep breath, and know that there are many things you can do to prepare (read more about them here). We can still avoid the worst-case scenario.

It’s okay to feel fearful of Covid-19. It’s just human.

I think I get why Trump is so eager to compare Covid-19 to the flu.

Flu is a regular occurrence, and its toll is something that we’ve grown numb to. Psychology teaches us a depressing lesson here: As we think about larger and larger numbers of people, our empathy and our ability to care and take action decreases. It’s called psychic numbing — and studies show our willingness to take action to protect others even decreases when the number of victims increases from one, to two.

By mentioning the flu numbers, Trump is hoping to get people thinking of big numbers, and induce numbing. He might want us to think: Tens of thousands of people die of the flu, this new disease isn’t a big deal.

Paul Slovic, one of the lead psychologists who has studied psychic numbing, says he doesn’t expect Americans to grow numb to this growing crisis. It hits on a lot of the psychological buttons that tell us to be fearful.

Slovic does call comparisons to the flu “misleading.” But he doesn’t think people are going to fall for it.

“People are not numb with regard to this new virus,” Slovic writes in an email. “This virus hits all the risk perception ‘hot buttons’ ... It is new, unfamiliar, and hard to control through individual or societal action. There is no vaccine and it spreads invisibly, adding to the difficulty of controlling it. It can be fatal and widespread (hence pandemic). All of these qualities ramp up the dread feelings that we have long known to be the major drivers of risk perception.”

It’s okay to be a bit scared in times like these. It’s natural, and extremely human. I can even understand why many people might be asking the flu comparison question themselves, in an attempt to maybe numb themselves to the stark reality we’re facing. (Trump, and other leaders, should know better, and not give people seeking psychological relief an easy out.)

But we can’t be numb. We can channel fear into useful tasks. The bigger concern is that people won’t act in the way they really need to. During a flu season, schools aren’t typically shut down; people don’t stop going to the movies. To fight Covid-19 requires a much larger disruption in our lives.

For what it’s worth, in his Oval Office address on March 11, Trump did outline the danger of the situation and gave basic, decent, public health advice. But it might not make up for the months of him trying to downplay the outbreak.

If you see people make the flu comparison, don’t be fooled into thinking that Covid-19 is an equivalent. It doesn’t look as bad as the flu in terms of raw numbers. But the top minds modeling this outbreak fear that will change. And, again, we really need to act differently than normal to prevent contagion and deaths.