Working coronavirus test kits promised soon in all US states after faults found

The US Centers for Disease Control and Prevention (CDC) said it aimed to have tests for coronavirus out and working in every US state by the end of next week, after the first test kits distributed were found to be faulty.

Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, said in a call with reporters on Friday that the agency found a way to use the test kits without the faulty component and also would be sending more tests out around the country.

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Messonnier also confirmed that there is still only one person who tested positive for coronavirus without the CDC knowing how or where they contracted it.

“It’s possible this could be the first incident of community spread, meaning the illness might have been acquired through an unknown exposure in the community,” Messonnier said. “It’s also possible, however, that a thorough investigation may show that the patient had exposure through contact with a returned traveler who was infected.”

Messonnier disputed accusations that the CDC initially denied a request to test the person in California. She said the CDC’s first record of a call asking about the individual was on 23 February and the agency has not said no to any requests for testing.

There are concerns that the count of coronavirus cases in the US is an underestimate because of low testing rates. While South Korea has tested more than 35,000 people for coronavirus, the US has tested 426 people, excluding those returned on evacuation flights, according to the Washington Post.

Messonnier said the US’s low case count could be attributed to early, aggressive containment strategies, such as focusing surveillance on people who had the highest risk of contracting the illness. But she did not directly address how limited testing could affect the case count.

The kits initially sent out by the CDC were found to be faulty, but Messonnier said as of Friday, labs could use those kits with a modification. The agency is also sending out more kits across the country. “Our goal is to have every state and local health department online, doing their own testing, by the end of next week,” Messonier said.

After issuing a serious warning on Tuesday that the spread of coronavirus in the US was inevitable, Messonnier offered a less dire picture of the outbreak on Friday.

“There certainly is the possibility of additional cases and we will continue to work aggressively to keep that number low,” Messonnier said. “We hope that if there is spread, that spread will be limited, and that any disease in the US will be mild.”

The US has seen a dramatic drop in travelers from China, which may have helped slow the spread of coronavirus, according to an article published in the New England Journal of Medicine on Friday.

The article, written by officials at the National Institutes of Health and the CDC, said if it is assumed that the cases of people who have no or mild symptoms is several times as high as the number of reported cases, the case fatality rate may be “considerably less than 1%”.

The authors said the US should still be prepared for coronavirus to gain a foothold in the US, which might require isolation of ill people, closing schools and working from home.