The fire is upon us. By now, the SARS-CoV-2 virus is either established or making itself at home in communities across the United States. This is a fact. We are all at risk of infection right now, some more than others, depending on where they live or the jobs they do. And it is only going to get worse.

If you don’t believe me, just wait for the report of the first case in your neighborhood. That’s coming, if it hasn’t happened already. Case counts are going to tick up across the country. While we expect the great majority to suffer only mildly, some people will get much sicker, and there will be deaths. Covid-19, the disease caused by the novel coronavirus, doesn’t seem to kill quickly, so it might take a while, but they are coming. Less than three weeks ago, Italy was reporting 121 cases. On Monday, authorities there put travel restrictions on the whole country, affecting 60 million people, until April 3.

So what we need to do now, before things get really bad, is think about how to protect the health-care systems we rely on and keep them from being overwhelmed by a surge of cases, as is already happening in Washington state.

And here’s the thing: You can help just by working from home, if your job allows it.

Viruses such as SARS-CoV-2 need to transmit. That’s obvious. If we could put every infected person in a sealed box and open it only once they were either immune or dead, we would have stopped the outbreak — but we would also have committed a hideous crime by denying the sick the care they need and deserve. Viruses spread on networks. They rely upon the ways in which we get together and allow infected folks to transmit unknowingly to everyone else. If we can stop that, we stop the epidemic. We just need to cut the links and suffocate the virus.

We know that the highways along which the virus spreads are human contacts. You are much more likely to be infected by someone you interact more closely with than by a stranger. To prevent members of their team from becoming infected, the recent World Health Organization mission to China conducted meetings in which participants sat a distance apart. At mealtimes, one person ate at each table. This is what is needed in a zone where covid-19 has run rampant.

We are not there yet in the United States, and we should not want to get there. Even though dropped balls at many levels have left us vulnerable to the risk of large covid-19 outbreaks and the social disruption that comes with them, there is still something that can be done. We need to set up roadblocks to the routes that would otherwise allow the virus to spread among co-workers and colleagues

That’s why many places are already setting up bans or restrictions on gatherings of large numbers of people. In my own community of Cambridge, Mass., transmission among workers attending a meeting at a local biotech firm has left several ill with the virus and dozens quarantined, and it probably ensured a local outbreak of unknown final size. If that meeting had happened remotely, this would not have happened.

This week, Boston was due to host the annual Conference on Retroviruses and Opportunistic Infections, an international meeting of doctors and scientists dedicated to caring for and researching HIV. At the last minute, the conference was switched to an online format, with talks viewed over the Internet. This must have been a difficult and expensive decision, and it was taken even after some attendees had already arrived in the city. But it was the right one.

Most offices outside California and Washington haven’t followed suit and ordered regular, daily work to be done at home. Switching to remote work for jobs that allow it would be less inconvenient and less costly than canceling big meetings, though, and it would also be a useful tool in fighting the outbreak. And we should do it as soon as possible. The virus has shown that it moves faster than expected. And changing behavior takes time, so getting started now will pay dividends.

It’s true that for many people, working from home is not an option. But if people who can work remotely sequester themselves at home, this helps protect workers who cannot. Vaccines work by immunizing folks who get them, while preventing them from becoming infected and transmitting diseases to others who did not get them. If enough people are vaccinated, we can completely drive the disease from our communities.

There is no vaccine for covid-19 yet, and there will not be one for some time, probably at least a year. Until then, we can still fight the virus by social distancing and denying it the opportunity to cause new infections.

It seems that most of the spread of the virus is by droplets or fomites, which means you need to be relatively close to an infected person for transmission — or to at least touch a surface soon after that person has touched it. Obviously, it can’t spread over the Internet (other things can, but not covid-19). Right now, it is hard to know what to recommend to people when it comes to social distancing in general, and you should follow local news closely to be alert to local transmission in your community.

Employers should realize that this is going to be with us for some time and prepare now. Managers can think creatively about how to transition the responsibilities of their staff to something that reduces opportunities for infection.

I want to be absolutely clear: Working from home is not guaranteed to stop you from getting the virus. It won’t. But it’s not about you. If you can work from home, it will delay your getting the virus. And that is a small but heroic act. Our communities have no population immunity to the virus, so it will spread like wildfire once it’s established. We probably have little choice about whether we are likely to get it. We can only do something about when. If all covid-19 patients show up to hospitals in a one-month period, the beds will fill up much more quickly than if some infections can be put off for another month or more.

Stopping the virus is what you try to do in the containment phase. We flunked that. Now the whole game is about ensuring that our medical system isn’t overwhelmed. In Wuhan, China, where the outbreak originated, nearly 30 percent of the infections in early case series were among health-care workers. The authorities built new hospitals to deal with the surge of seriously ill patients. One of the explanations for what seems to be an elevated case fatality rate in Wuhan relative to other places may be the burden on health care. And I’ve not even mentioned the consequences for people who require care for life-threatening conditions that are not caused by the virus: If the beds and respirators are all being used by covid-19 patients, what will happen to the people with other life-threatening illnesses who require breathing support?

Your friendly neighborhood doctor will tell you that a bad flu season can put a huge strain on the rest of the health-care network. At a minimum, we expect this to be like a really bad flu season, and it could easily be worse.

Not everyone will be able to take this advice. If you can, you should. If your supervisor grumbles about it, show them this article. They will have to listen to the virus soon enough. And they will wish they had listened to me instead.

Trump may think he can sugarcoat coronavirus, but media critic Erik Wemple says it is time for the government to speak with one clear voice about public health. (The Washington Post)

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