Just as access to COVID-19 tests was ramping up in many areas across the country, some testing sites have been forced to suspend operations because of violence and protests in recent days.
The temporary closures — from California to Florida — are sure to hamper efforts to control the spread of the coronavirus, particularly as social distancing has given way to mass gatherings of potentially contagious people who don't know they're infected.
"The way we move forward with this pandemic is to have testing be as widely available as possible," said Dr. Amesh Adalja, an infectious-disease physician with the Johns Hopkins Center for Health Security.
"Any disruption to testing is going to make it harder to find cases," he said.
Some testing centers, such as one in Lee County, Florida, were closed for a short time because the Florida National Guard personnel who ran the site were sent to help law enforcement elsewhere in the state.
Other sites were forced to close early or shut temporarily because of safety concerns, or where mandatory curfews were in place.
"Los Angeles County is in the midst of fighting an unprecedented pandemic while also facing a state of emergency that impacts public safety," Christina Ghaly, the director for the L.A. County Department of Health Services, said in a statement on the department's website, which lists testing locations that were closed or had limited hours Tuesday. "We need to ensure our testing sites are safe for both patients and staff."
COVID-19 testing was also limited in Illinois Tuesday afternoon. The head of the Illinois Emergency Management Agency ordered the state's community-based testing sites to close for 24 hours "out of an abundance of caution to protect the staff and those utilizing the services," according to a statement from the Illinois Department of Public Health.
Pennsylvania, too, had testing outages.
"We are aware that some COVID-19 testing locations may be temporarily closed due to the situation affecting our country," Pennsylvania's secretary of health, Dr. Rachel Levine, said in an email to NBC News.
Levine encouraged citizens to "take steps to protect one another," including wearing masks and remaining socially distant when possible. Indeed, research published Monday shows how keeping physical distance of at least 3 to 6 feet is the most effective way to slow the spread of the coronavirus.
But that advice continues to be ignored, even in peaceful displays of solidarity, increasing the risk of COVID-19 transmission.
And now those groups, in some cases, have more limited access to testing. "These are all converging factors that are going to magnify the impact" of the virus, said Adalja, especially in communities of color already disproportionately affected by COVID-19.
An April report from the Centers for Disease Control and Prevention found pre-existing conditions, such as diabetes, high blood pressure, obesity and asthma, were associated with worse outcomes of the coronavirus. Those underlying conditions tend to be more prevalent in African American communities, a disparity that's been documented repeatedly in recent years.
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Political leaders in Georgia and Minnesota urged protesters get tested for COVID-19 within the coming days and weeks, as well as work to keep one another safe.
Minneapolis, where George Floyd died in police custody last week, sparking the nationwide protests, remains a "hotspot for COVID-19 spread," said Jan Malcolm, Minnesota's health commissioner, in a statement. "We are also concerned about the continued disproportionate impacts of COVID-19 on people of color in our state."
"We need the help of everyone involved to prevent additional suffering and preventable death by following the public health guidelines to limit COVID-19 spread," Malcolm added.