Unpacking the Asymptomatic Transmission Controversy
If you spent any time on the internet yesterday, you probably saw news stories with confusing headlines about the World Health Organization (WHO) declaring asymptomatic COVID-19 transmission “very rare.”
Wait, what? Haven't we been wearing masks and staying home for months because we can spread the virus even if we're not experiencing symptoms? And haven't studies shown asymptomatic spread is a major route of transmission? Comments from Maria Van Kerkhove, the WHO’s technical lead for COVID-19, seemed to suggest otherwise.
I was confused, too. So I spoke with Van Kerkhove after yesterday’s press conference, and she clarified a few points:
Asymptomatic transmission is possible. Van Kerkhove said she never meant to suggest otherwise—she only meant to say that people who have symptoms of COVID-19, like cough and fever, seem to be responsible for the bulk of viral spread.
The data are still very much coming together. There’s a lot the WHO doesn’t know about the virus, including how often asymptomatic people pass it on, and the agency is “not ruling anything out,” Van Kerkhove said. Her comments were based on a number of published studies (cited here), as well as some unpublished contact-tracing reports from WHO member states, including China.
There are tricky semantics at play when it comes to defining asymptomatic transmission. In the WHO’s eyes, an asymptomatic person is someone who is infected, but never develops symptoms; about 15% of cases fall into this category, Van Kerkhove said. Someone with mild symptoms—even so mild they don’t realize they have COVID-19—is not "asymptomatic." Neither is someone who’s been infected but hasn’t developed symptoms yet (they would be considered “presymptomatic”). For people who eventually show signs of illness, there’s usually a delay of around five days between when they’re infected and when symptoms begin appearing. This pre-symptomatic phase is difficult to distinguish from being asymptomatic, but it is categorized differently.
Some health experts criticized the WHO for failing to clarify these nuances. Others said there weren't great data to back up the WHO’s claims, and expressed concern that the organization’s comments could result in fewer people wearing masks or practicing social distancing. Given all the unknowns and caveats, the consensus in the health community is that we shouldn’t ease up on those measures yet.
Van Kerkhove said the same. She emphasized that individual precautions, like wearing masks and limiting social contact, remain important pieces of a broader COVID-19 containment strategy—one that must also include contact tracing and isolating sick people.
More than 7.1 million people around the world had been sickened by COVID-19 as of 11 PM eastern time last night, and more than 406,000 people had died.
Here is every country with over 100,000 confirmed cases:
People in countries around the world have joined many of those in the U.S. in protesting racism and police brutality. In Germany, officials are begging demonstrators to continue following social-distancing guidelines and wearing masks, the Associated Press reports. “Both things must be possible: to demonstrate peacefully, which is a fundamental right, and keep to the [social distancing] rules,” said Steffen Seibert, a spokesman for Chancellor Angela Merkel.
An editorial published in one of Brazil’s largest newspapers said the country’s government is trying to pull off a “statistical coup” by refusing to publish full and current COVID-19 data. Official data show that Brazil has one of the world’s most severe COVID-19 outbreaks, even with imperfect reporting practices and a president who routinely plays down the gravity of the crisis. Experts’ fears were stoked even further when the country’s health ministry late last week pulled down a webpage related to coronavirus data. The page is now live again (with some data missing), but critics remain concerned Brazil is trying to hide the extent of its outbreak.
Tanzania has also stopped publishing COVID-19 data, sparking concern from the WHO and other health authorities. President John Magufuli controversially declared the country coronavirus-free, crediting citizens' prayers for beating the virus. But the WHO is worried about the country’s hands-off containment strategy.
The Situation in the U.S.
The total number of COVID-19 diagnoses in the U.S. surpassed 1.9 million as of 11 PM eastern time yesterday, and the death toll neared 111,000.
On June 8, there were 17,250 new cases and 482 new deaths confirmed in the U.S.
Twenty-eight states are violating U.S. Centers for Disease Control and Prevention (CDC) guidance by not including probable but unconfirmed COVID-19 cases in their official data, CNN reports. Failing to tally these likely positives could leave officials without an accurate view of how prevalent COVID-19 remains within their borders, potentially leading them to reopen more quickly than they otherwise would.
That’s especially concerning as case counts continue climbing in many states. Fourteen states and Puerto Rico have recorded their highest seven-day averages for new coronavirus cases in June, according to a Washington Postanalysis.
In earlier stages of the pandemic, several cruise ships became floating coronavirus breeding grounds. Now, new lawsuits allege that cruise line Princess Cruises did not do enough to protect its passengers from the virus’ spread. COVID-19 spread widely on board two Princess ships, the Grand Princess and Ruby Princess.
All numbers unless otherwise specified are from the Johns Hopkins University Center for Systems Science and Engineering, and are accurate as of June 8, 11 PM eastern time. To see larger, interactive versions of these maps and charts, click here.
WHAT ELSE YOU SHOULD KNOW
How Refugee Workers Are Helping the U.S. Fight COVID-19
Some foreign-born doctors who live in the U.S. but do not have American medical licenses are finding creative ways to join the COVID-19 relief effort—even if they can’t treat patients directly. Read more here.
Most Nursing Home Workers Feel Their Lives Are at Risk
Despite the intense focus on nursing home safety following several deadly clusters of COVID-19 in long-term care facilities, many nursing home employees still feel their lives are at risk when they report for work. Read more here.
Minority-Owned Businesses Are Taking a Hit
By now, we know that COVID-19 disproportionately affects people of color in almost every way. As TIME political correspondent Alana Abramson reports, that includes a squeeze on small businesses. Read more here.
Feeding Crowds In a Crisis
As food banks scramble to keep up with coronavirus-related demand, community organizations could take a cue from gurdwaras, Sikh houses of worship. Gurdwaras have a long tradition of providing free meals to anyone in need, and they’re rising to meet the challenges presented by COVID-19, the New York Times reports. Read more here.
A Reckoning For the Medical Community
Protests driven by the killing of George Floyd have sparked conversations not only about police brutality, but about the myriad ways racism affects human health, STAT reports. Read more here.
Thanks for reading. We hope you find the Coronavirus Brief newsletter to be a helpful tool to navigate this very complex situation, and welcome feedback at coronavirus.brief@time.com.
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Today's newsletter was written by Jamie Ducharme and edited by Alex Fitzpatrick.
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