The message seemed so obvious. Yet it was being blared constantly from truck loudspeakers and pasted on billboards and even printed on T-shirts throughout Sierra Leone’s capital city in the summer of 2014:

“Ebola is real!”

The world’s worst outbreak of the dreaded hemorrhagic fever was burning through West Africa at that very moment. Thousands already were sick and dying. To doubt the viral threat seemed bizarre. Superstitious.

To a reporter sent to cover the outbreak, the “Ebola is real!” message was confusing. How can they not know the virus is real?

But now it seems some Americans need to hear a similar message: Coronavirus is real!

Vice President Pence even said at a coronavirus task force news conference Tuesday that the threat of the virus “can be very significant and very real.”

The novel coronavirus — SARS-CoV-2 — is real. But many people are not acting like it.

You can sense the exasperation of public health officials as they plead for people to stay home as much as possible and to practice social distancing.

The rule of thumb among doctors and journalists during the Ebola outbreak when I was there was to act as though everyone in public was contagious. Because you didn’t know.

That applies to the coronavirus pandemic, too.

Any other argument — that it’s just the flu or it’s not so bad — is just a version of doubting whether the virus is real.

I never imagined that an outbreak in the United States would so closely resemble what I witnessed in Sierra Leone six years ago.

But the parallels are everywhere.

The fear is familiar.

So is the complacency.

Schools were closed and large gatherings banned in both countries to slow the virus’s spread.

There is the same anger about the government’s response, the same cries that the hospitals are not prepared, that masks and gloves are in short supply.

Both outbreaks delivered crushing blows by killing doctors who were viewed as public heroes — Li Wenliang, an ophthalmologist in Wuhan, China, who was among the first to sound the alarm about the novel coronavirus and last month died of it, and Sheik Umar Khan, a virologist in Sierra Leone who led his country’s fight against Ebola until it killed him in July 2014.

The viruses are different in important ways: The coronavirus is more contagious than Ebola. It is also less deadly.

But no one underestimated Ebola.

The pathogen has haunted the world since it was discovered in the 1970s.

That respect led to fear — which probably saved lives.

Preparing to travel to Sierra Leone, I’d followed the advice of a collection of infectious-disease doctors and other journalists. It was ad hoc and probably over the top. But it was not insufficient.

I buzzed my hair, shaved my face clean and trimmed my fingernails to eliminate places where the virus could build up.

I probably didn’t need to do that.

My suitcase carried full-body Tyvek suits, the kind of white protective coveralls that hospital staff members wear now. I had ample supplies of disposable exam gloves, splash goggles, rubber boots and N95 respirator surgical masks — versions of the ones suddenly gone from U.S. store shelves. I also had a giant tub of Clorox Healthcare bleach germicidal wipes along with “super disinfectant wipes,” plus three large bottles of hand sanitizer.

I never wore the Tyvek suits on my two-week reporting trip.

I donned a face mask just once — when we conducted interviews outside an Ebola hospital ward.

Moving through the streets of Freetown, Sierra Leone’s crowded capital city, I quickly discovered that I didn’t really need most of the protective gear.

What I needed was much simpler — distance and clean hands.

Fear was a good instructor.

It was the only way to keep safe. Being courageous against a virus got you sick.

And it wasn’t just me. Everyone seemed on edge. There were stories of researchers who studied Ebola in the lab who declined the opportunity to chase the virus up close. And there were the doctors who came from around the world to work in the Ebola treatment centers, stressed out by the danger but driven by their mission to help.

During the outbreak, every shop kept outside its doors a small tub filled with diluted bleach water. Everyone turned the spigot and rinsed their hands. Anyone who skipped hand-washing was called out, castigated.

It was a rudimentary mitigation method.

But it served another purpose, too. The sight of the colorful water bins was confirmation that everyone was in this together and taking it seriously.

I frequently used my own sanitizer gels and wipes. I wiped down everything I might touch. Pens. Silverware. Doorknobs.

It felt insane. But it was also reassuring. I was doing what I could.

No one shook hands. Interviews were conducted at a distance of about six feet. It felt odd. And it wasn’t perfect. I remember sidling up to talk into someone’s ear on a busy road. Curious nurses leaned in to see what I was writing.

During an interview with a group of young men, one of them accidentally spat a tiny amount as he talked, despite the distance.

I can still feel that tiny speck landing on my eyelid. Panic soared. I kept taking notes, but my mind had moved on.

I hoped I would be fine. But like the coronavirus, Ebola has a long incubation period. I wouldn’t know for certain if I was okay for a couple of weeks.

When I returned home, I spent the next two weeks in the basement, away from my family, in self-quarantine. It was voluntary. No one had screened me at the U.S. airport. No local health authority checked on my whereabouts.

I simply didn’t want to get anyone sick.

Now, the novel coronavirus has shown what it can do.

It’s real.