For weeks now, we’ve watched the COVID-19 pandemic spread across the United States. During much of that time, it’s seemed like the only thing to do is hunker down, wait, and hope. We hope that a vaccine will arrive, even though we can’t be sure how long that might take, or whether an effective vaccine is even possible. We hope that those who have had the virus will be able to return to work—never mind that we have yet to see proof of durable immunity. Maybe wearing masks and sheltering in place will make the virus recede. Perhaps summer will kill it, even though it has spread in the year-round heat of Singapore and other places. We seem to be hoping that something miraculous will happen—that, somehow, the virus will leave of its own accord.

In the nineteen-nineties, as a co-founder of the global organization Partners in Health, I helped fight multi-drug-resistant tuberculosis in the developing world. In the early two-thousands, I led the World Health Organization’s H.I.V./AIDS department; afterward, as the president of the World Bank, I took on cholera in Haiti and Ebola in West Africa. I’ve been fighting pandemics for most of my adult life. That front-line experience has taught me that hope is a wonderful thing, essential to any difficult undertaking. But, especially when it comes to infectious disease, hope is of little use unless it’s accompanied by a bold and vigorous plan.

South Korea, which so far has managed the pandemic better than any other country, has pursued such a plan. There, people talk about COVID-19 as if it were a person. Leaders at the Korean Centers for Disease Control and Prevention have told me that the virus is sneaky, nasty, and durable—and that it has to be hunted down. In Singapore and China, large teams of public-health workers are on a war footing, confronting the virus like the mortal enemy it is. In the face of such an enemy, America’s passivity has been puzzling and unworthy of the best episodes in our history. The time has come for us to get into the fight. It’s not too late: we can still mobilize and start hunting down the virus. What’s needed is a decisive investment in a public-health initiative big enough to meet the challenge.

What weapons are available to us? Important insights come from a recent study of more than thirty-two thousand coronavirus patients in Wuhan, China, published in the prestigious Journal of the American Medical Association and conducted as a coöperative effort by the Harvard T. H. Chan School of Public Health, in Cambridge, and the Tongji School of Public Health, in Wuhan. The study outlines a strategy that has brought the coronavirus to heel, at least for now.

At first, the virus ran unchecked in Wuhan, and was highly transmissible. The authorities locked down the city, and the “flattening of the curve” began. The rate of transmission dropped dramatically. And yet this wasn’t good enough. The Chinese authorities worried that, if they lifted the lockdown, the virus would spread again as quickly as before. Enduring the pain of lockdown without a path to a virus-free future—that’s where we, across the U.S., find ourselves today.

And so the health officials in Wuhan adopted a more aggressive approach. They began widespread testing, finding the people who were infected. They found out whom those people had been with, got in touch with those individuals, and tested them. They quarantined people who they thought might have the virus and hospitalized those who were sick. And they scaled up their health-care system, building more than a dozen new hospitals dedicated to treating patients in the early stages of coronavirus infection. Five elements, five weapons: social distancing, contact tracing, testing, isolation, and treatment. After Wuhan began using these weapons simultaneously, the transmission rate dropped again, to the point where any single case led to less than one more. Once that happens, an epidemic dies.

South Korea, Singapore, Taiwan, Hong Kong—by using these five weapons, they, too, have gained control over the virus. Evidence from countries around the world, including Germany and Australia, strongly suggests that only this full, five-part response is capable of stopping COVID-19. Italy has yet to deploy the full arsenal; there, the virus’s spread has slowed, but not enough to stop the outbreak and allow a restart of the economy. Spain faces the same problem. In the United States, we are seeing a flattening of the curve in places where social distancing has been practiced rigorously. But we haven’t yet used the full arsenal, either. We’re not going on the offensive, taking the fight to the virus and stopping its transmission.

We need to change our strategy. Recent events in Massachusetts may signal a new beginning. The state’s governor, Charlie Baker, has embarked on a plan that includes full-scale, statewide testing and contact tracing, which will be linked to an effective quarantine-and-treatment system. A consortium—made up of state and local departments of health, the state’s health-insurance marketplace, and private companies, including Accenture and Salesforce—is working to build the system and hire hundreds of new employees by the end of this month. Partners in Health is drawing on its global disease-fighting experience to help coördinate the effort. It’s a true mobilization: the state is taking on the virus directly, using the five-element anti-pandemic arsenal. (I am a special adviser to the effort.)

Many people have the impression that it’s too late for contact tracing. It’s useful for keeping an infection out of the country, they say, but it’s too hard once the disease is widespread. As veterans of previous campaigns against epidemics, we can say with certainty that this is a misperception. We agree that it is late, but countries that have succeeded in suppressing COVID-19 have shown that contact tracing is effective even at the peak of an epidemic. In the fight against infection, you’re always late. Lateness just means that there’s no time to waste.

Tracing, of course, must go hand in hand with fast and accurate testing. We’ve all heard that no health authority in the United States currently has access to testing in the volume that’s needed. But many new kinds of tests are in the works or on the way. Using currently available technology, Massachusetts has already managed to dramatically increase the number of tests that it administers, from forty-one on March 9th to more than eight thousand on April 17th. The Broad Institute has pledged to use its massive, state-of-the-art laboratories to process many thousands of tests per day. Other states could achieve the same kind of results, and could also leverage labs at their local companies and universities.

We’ve been told that many Americans won’t put up with quarantine and isolation. But the truth is that most people, once they learn that they’ve been exposed to the virus and may get sick in the near future, understand why they need to stay home. What’s required is support. You can’t stay at home if you don’t have any food; you can’t answer a call from a contact tracer if you have no minutes left on your phone, or no phone at all. You might need help explaining what’s happening to your boss. You’ll need reassurance that you’ll be able to support your family. The countries in Asia that have succeeded in fighting the virus have provided just this kind of support. Helping people who are infected or at risk of infection stay home or at a designated facility requires money and staff. But there are many Americans who would leap at the opportunity to help their neighbors and their country. And, compared with the stimulus packages that we have passed and continue to contemplate, the cost of hiring them is a bargain.