Mr. Trump’s new crown is a warning to the world that testing alone will not stop the virus from spreading.

Yesterday, U.S. President Donald Trump, 74, announced in a Twitter post that he and his wife Melania had contracted the new crown virus,media reported. Even with the White House’s extremely strict new crown controls, mr. Trump and others, like everyone else, are still at risk of contracting the virus — in fact, he has repeatedly ignored suggestions that could have reduced his risk of contracting the virus.

Mr. Trump's new crown is a warning to the world that testing alone will not stop the virus from spreading.

It’s clear that Trump has more virus-control resources than most people in the U.S.: he’ll be tested regularly for COVID-19, as will the people he regularly contacts. In defiance of other public health recommendations, testing was not enough to keep the virus out of his circle. Mr. Trump’s diagnosis is certainly a vivid reminder that testing does not organize the spread of the new coronavirus. It must be combined with other protective measures such as keeping a social distance, wearing a mask, washing your hands, etc. to truly protect people.

Since the beginning of this year, it has been known that the virus can spread rapidly and easily from person to person and is difficult to avoid. Most cases may be mild and many will be fine, but the virus will continue to exist. In crowds, in poorly ventilated rooms, when people stay together for long periods of time, when they do not take precautions such as wearing masks the virus can breed.

Mr. Trump has spent months playing down the effects of the deadly virus and minimize the importance of protections. He continued to hold and attend rallies, some indoors and often without a mask. The same is true of the people around him.

Mr. Trump's new crown is a warning to the world that testing alone will not stop the virus from spreading.

Frequent testing does not compensate for all those dangerous activities that can infect the virus. COVID-19 tests on the market, especially fast tests, may miss people who are in the early stages of infection and have few viruses in their bodies. Some people may have tested negative today, but the next day’s test was positive — they may have been contagious.

Testing can help control the spread of disease only if people act on the results. The CDC recommends that people isolate themselves from others when they learn that they have been exposed to the virus. Instead, Mr. Trump reportedly kept his schedule, including attending a fundraiser, after learning that he might have been infected with the virus. This may put many others, including service personnel, at higher risk of infection.

Like other 74-year-old male patients, President Trump is at high risk of developing severe cases of COVID-19 — a virus that is most dangerous to people over 65 and more likely for men than women. But once again, he will prove unique among those who have also tested positive: he will receive the highest quality of care.

This is a noteworthy case, but in many ways it is also a standard case for COVID-19 in the United States, which remains the world’s largest outbreak of COVID-19.