Former Vice President Joe Biden, US Sen. Bernie Sanders and even President Donald Trump need to dramatically change the way they are campaigning.

It’s time for them to declare a détente and end all large rallies with supporters as a way to help combat the spread of the coronavirus.

Both the Biden and Sanders campaigns announced Tuesday that they have canceled rallies in Ohio, citing public health concerns in that state. That’s a good start and I know it must have been a difficult decision to make with so much on the line in the race for the Democratic nomination.

But the campaigns — as well as others for state and local office — must change behavior or else they are likely to contribute to the spread of this new disease.

All three men are in their 70s, which puts them at greater risk of catching COVID-19 and suffering a severe case of the disease.

Democratic presidential candidate Sen. Bernie Sanders greets supporters after speaking during a campaign rally Monday in St. Louis. (AP Photo/Jeff Roberson)

I’m not suggesting that they curtail their events just for their own protection, although that’s important. They need to end the large rallies to protect their supporters and to protect the communities where they are campaigning.

This idea, best I can tell, was first proposed by former Democratic presidential candidate Pete Buttigieg and reported by Politico earlier this week. The Sanders and Biden campaign took limited action on Tuesday.

As of Tuesday afternoon, Maine has no confirmed cases of COVID-19, but it’s only a matter of time before testing catches up with reality. It’s almost certain that the disease is here and probably has been for sometime.

Other countries around the world, including Italy, Japan and China, have taken drastic steps in their efforts to control the spread of the virus.

The United States is reacting more slowly, but we are beginning to see the cancellation of large events and colleges and universities move to online teaching. Businesses in Maine and around the country are placing limits on non-essential travel and planning for disruptions in their workforce. Smart companies are putting in place contingencies for remote-work protocols.

There’s still a lot that we don’t know about the coronavirus. It’s unclear how quickly it can spread and how dangerous it is. So far, the mortality rate is high, but that’s potentially influenced by an underestimate of the number of people who are actually infected.

Each of us has a job right now. We must do everything that we can to slow the spread of the disease.

The reasons go beyond our personal health and the health of our families. If we can slow the spread of the disease — flatten the curve, as the medical community says, of infections — we can help our health care system prepare and limit a dangerous situation where the number of sick people overwhelm hospitals, doctors’ offices and clinics.

You’ve likely heard the drill by now: We all should be following better hygiene practices, including staying home if we’re sick, washing our hands frequently, keeping six feet away from others who might be ill and covering your cough or sneeze.

Given the circumstances, then, the men who are vying to lead our country need to recognize the situation for what it is and adjust their campaigns accordingly. That starts with no more big rallies, anywhere.

It’s a big ask. Trump and Sanders, particularly, thrive on large, boisterous crowds. They feed of the energy, and it’s a big part of their campaigns.

Trump for his part seems confused about coronavirus, how it spreads and why it posses such a risk. His administration has performed poorly and reacted slowly, increasing the threat to the country.

But for all the candidates remaining for president — and, in fact, candidates for local and state offices — it’s time to show that you take your leadership responsibility seriously.

As the list of big events, such as South by Southwest, are canceled, schools colleges and universities transition to remote learning, and businesses constrict travel, it’s time for politicians to follow suit.

I love political events and try to go with my kids as often as possible. On Sunday, I went to the Portland Democratic caucus, where between 250-300 people gathered to conduct party business and elect delegates to the state convention in May.

It was fun day filled with community activism, candidate speeches and catching up with other voters.

But as I look ahead, our politics have to match our time. And at this time, all of us — including Joe Biden, Bernie Sanders and Donald Trump — have a responsibility to the country and to our communities to do everything we can to slow the spread of this disease.

And that means changing the way we campaign. Leadership demands tough decisions and this is a test for all the candidates for president that they can’t afford to fail.