How Coronavirus Testing Varies by Country and State, in Charts

Without adequate testing, it's challenging for public health officials to know the extent of the outbreak's spread

A chart showing the number of coronavirus cases past 100 by day by counrtry.
Amy O'Kruk/NBC

COVID-19, the disease caused by the coronavirus, has spread much quicker and farther than MERS and SARs and any other epidemic that has caused panic in recent memory. 

The outbreak emerged in Wuhan, China, in December, and has spread around the world. President Donald Trump declared a national emergency on March 13, and almost every state has followed suit as the U.S. death toll passed 700 and the number of those infected passed 50,000. Amid a country-wide testing shortage, the actual number of COVID-19 carriers is likely much higher.  

How leadership at the country and state level have tackled the emerging public health crisis differs widely. The most successful countries have shown that aggressive testing is the best way to pinpoint and isolate the disease, halting its spread. 

The chart below shows the virus’s trajectory in different places. While some countries, such as Italy, have been ravaged by the coronavirus, others such as South Korea and Singapore have managed to slow its spread.

South Korea in particular has been lauded for its robust testing program and extensive efforts to isolate infected people and swiftly quarantine their contacts. The government has implemented creative measures, harnessing the power of cell phone data to create a publicly available map that people can use to determine if they have come into contact with someone who has tested positive.

Coronavirus Cases in the United States Are Accelerating

Total number of cases following each day with more than 100.

Source: Johns Hopkins University, Mar. 23.
Credit: Amy O’Kruk/NBC

Without adequate testing, it's challenging for public health officials to know the extent of the outbreak's spread and to determine how deadly it is.

Models published by academics around the world paint a grim picture if nothing is done: case levels quickly overwhelm what many countries’ critical-care infrastructures can handle. In a highly populated place like the U.S., that could translate to millions dead from either the virus itself or hospitals that are too overwhelmed to sufficiently treat inevitable cases of heart failure, injuries or cancer crises.

Testing Varies Wildly Across Countries

Recent data shows that about 1,079 people per million have been tested in the United States, a smaller proportion than most other countries where data is available.

Source: COVID Tracking Project, reports from country health departments, Mar. 25
Credit: Amy O’Kruk/NBC

Across the U.S., states, have responded in radically different ways to this new threat. An increasing number of states, including California, New York and Illinois, have issued shelter in place orders, requiring millions of residents to stay in their homes with the exception of essential activities, such as trips to the grocery store or pharmacy.

On the other hand, in Florida, Gov. Ron DeSantis has faced criticism for refusing to issue a shelter in place order and being slow to shut down places that attract big groups, with large crowds gathering on Florida’s beaches as recently as last weekend. Trump said Tuesday he hopes to reopen the country for business by Easter.

Public health officials have stressed the dire need for better containment strategies and testing. Dr. Scott Gottlieb, former head of the Food and Drug Administration, has been direct about the steps the U.S. must take, pointing to mitigation — things like closing public spaces, work from home and shelter in place — and widespread testing to diagnose even mild and asymptomatic cases. 

“As we slowly take our foot off the break of mitigation we’ll have to gradually rely on case containment strategies to keep sparks of infection from turning into brush fires,” Gottlieb said in a tweet on Saturday.

New York is Leading the Effort to Identify Virus Carriers

Source: COVID Tracking Project, Mar. 23.
Credit: Shelly Cheng/NBC, Amy O’Kruk/NBC

While some places such as New York City, the epicenter of the outbreak in the U.S. with 25,000 positive tests, are past the window for containment, advocates say it remains doable in other cities and towns. 

Overall, the United States will know within weeks whether its curve and future looks more like South Korea’s or Italy’s.

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