It’s been six months since the United States reported its first coronavirus case, and getting a test can still take days. National labs are overwhelmed, leaving people to wait as much as two weeks for results. Every day that testing falls short is another day the virus can spread undetected, costing lives and delaying the reopening of our economy, schools and society.

As states try to control the virus and as Congress considers the fourth Covid-19 relief bill, New York offers important lessons on how to fix the testing mess.

Over the last 10 weeks, New York has used testing to not only flatten the curve, but actually reduce the rate of infection since our phased reopening started. We have kept our testing rates high through partnerships with federal and local governments. In February and early March, New York worked with the Food and Drug Administration to gain the necessary approvals to begin using our own coronavirus test and mobilize a network of hundreds of labs. In April, when our labs were struggling because of shortages of a necessary chemical ingredient, reagents, President Trump and I reached an agreement that helped double New York’s capacity.

Here’s what states should do to build a sustainable testing operation, and how Congress can help.

Mobilize smaller local labs. Almost all states are now using a handful of national testing companies, and they are overwhelmed. New York has managed to avoid the delays because more than 80 percent of our testing does not depend on the national laboratories experiencing long turnaround times for results.

In the early days of the pandemic, New York organized hundreds of local labs to conduct as many tests as possible. We moved equipment sitting idle to labs that could run them around the clock. Today, more than 250 labs in the state report results each day — some conducting 10 tests daily, some thousands. All together, New York can now conduct on average 65,000 tests a day.

And while any lag time is not ideal, over the past week, more than 85 percent of New York’s tests took a median of just two days (and an average of three days) from collection to result, and lags will continue to shorten as we move tests from labs with backlogs to labs without.

Each state should mobilize its own network of laboratories, which will take pressure off the major national labs, reduce reporting times and arm states with data that can help slow the spread of the virus. Congress should dedicate money to help develop the capacity of local laboratories and ensure federal agencies can provide speedy approvals and technical assistance to states.

Streamline the supply chain. In New York and other states, there are high-capacity labs running at partial capacity because they don’t have enough supplies.

How can it be, six months after America’s first case was reported, that the United States still doesn’t have an adequate supply chain? What labs need — reagents and plastic pipette tips — are not complicated to manufacture. They can, and should, be made in mass quantity, immediately, and here at home.

New York invested $750,000 in Rheonix, an Ithaca-based manufacturer, to build lab instruments and make reagent kits, which are now being used for thousands of tests daily. States should tap their local manufacturing companies to compensate for international shortages, and Congress should allocate funding for businesses that fill these needs.

Invest in innovative solutions. The Food and Drug Administration recently approved pooled testing, where multiple samples are run at once, increasing capacity and saving lab supplies. But for one national lab, the approved pool size is just four samples. In Wuhan, China, up to 10 specimens were pooled, allowing the city to increase its capacity to 1.5 million tests daily, up from 46,000 tests daily.

The federal government should direct research money so that labs can increase their pool size, while ensuring accuracy. With flu season on the way, Congress and federal agencies should also invest in developing widely available single tests that can detect multiple respiratory viruses, including the coronavirus and different types of influenza.

Congress should also invest in developing more tests that can give results in minutes and that can be administered at workplaces, not just labs. The F.D.A. has approved only a handful of these devices, and they are not widely available.

Fund all necessary testing. Currently, under federal rules, “medically necessary” testing is free for those with Covid-19 symptoms, as well as asymptomatic people who have been exposed to the virus.

But states should be able to conduct broad community screening — 40 percent of infected people are asymptomatic — to detect the virus and control its spread. For example, Congress should ensure testing is free for individuals who attend mass gatherings, regularly ride public transportation or interact with members of the public at work.

New York is proof that a real testing strategy can control Covid-19. But our future success depends on other states to do the same — a virus anywhere is a virus everywhere.

There can be no economic recovery without each state having a sustainable testing strategy. New York has already advised other cities, and we stand ready to help any state or local government replicate our success.