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April 9, 2020

Experts Warn High Rates of Positive COVID-19 Tests Show U.S. Not Ready to Relax Restrictions; Also Note Signs in Africa of “Silent” Spread of Disease

Johns Hopkins Bloomberg School of Public Health and Bloomberg Philanthropies experts brief media on domestic and global COVID-19 state of play

The high percentage of positive results from COVID-19 tests indicates the United States has “not yet found the edges of the outbreak” and is not ready to transition from a stay-at-home strategy to a cautious return to normalcy, said Dr. Caitlin Rivers, a senior scholar at the Johns Hopkins Center for Health Security at the Johns Hopkins Bloomberg School of Public Health.

Rivers spoke at a virtual media briefing Thursday alongside Dr. Kelly Henning, who leads public health programs at Bloomberg Philanthropies, where they answered questions about a roadmap for fighting the pandemic and the capacity around the world to do so.

Rivers said one indicator that the United States needs to stay the course with stay-at-home efforts is that currently 20 to 40 percent of COVID-19 tests are coming back positive—a much higher number than in places where the outbreak seems to be ebbing.

“In South Korea…about 2 percent of their tests come back positive, and in Germany, as of a couple of weeks ago, only about 7 percent of their tests were coming back positive,” she said. “So when you are seeing 20, 30, 40 percent of tests coming back positive in the U.S., it shows we need to keep expanding capacity, expanding testing and finding more cases.”

Rivers is co-author of a report that envisions a four-phase endgame to winning the battle against COVID-19. But she emphasized that experts recommend a focus on capabilities, “not a timeline.” And right now, she said, the capabilities required to move from the current focus on slowing transmission—like sufficient testing and health care systems equipped to safely treat everyone who is sick—are not yet in place.

Henning agreed, adding that “we really need public health teams in each locality…to move us forward in understanding when it’s safe to begin relaxing physical distancing.” And she said that when that transition finally begins, businesses in particular will “need additional resources” to support a safe return to work.

“Businesses will need to think about the distance between their employees, ensuring hand sanitizer and hand washing is very available, and other elements that will come into play as we slowly move forward to restart the economy,” she said.

Meanwhile, alongside its efforts to support COVID-19 response in U.S. cities, Henning said Bloomberg Philanthropies has committed $40 million to accelerate the fight in places like sub-Saharan Africa. She said there are worrisome signs that “this outbreak is silently moving forward in lower- and middle-income countries.” While in much of the developing world a lack of testing has made it difficult to assess the status of COVID-19 infections, Henning said in sub-Saharan Africa, recent reports of an increase in pneumonia-like diseases could be an indicator of rising cases of COVID-19.

Henning said the key concerns she is hearing from low and middle-income countries involve the lack of personal protection equipment for health care workers and lack of testing. She said one positive development is that the recent experience with Ebola has given some countries in Africa experience and capacity that could be critical for slowing the spread of COVID-19.

“Their ability to do things like contact tracing, where one goes out to find all those in close contact with a case, is fairly good considering their limited resources,” Henning said.

Rivers was asked about any guidelines for allowing professional athletes to start playing again. For example, there are reports that Major League Baseball is considering a plan that would allow games to resume in empty stadiums—no fans allowed—around the Phoenix area as soon as early May.

She said there are a number of distinctions that have to be considered, such as contact versus non-contact sports, indoor versus outdoor sports, and allowing fans versus players only. But she said that she did not have a “blanket recommendation.”

"Certainly in April we're all staying home," she said. "That's the right thing to do and we should stay focused on that for now."

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Media contacts for the Johns Hopkins Bloomberg School of Public Health: Barbara Benham at 410-614-6029 or and Robin Scullin at 410-955-7619 or

For more information on the novel coronavirus and COVID-19, visit our COVID-19 Expert Insights site.