CLEVELAND — It was the sound bite heard ‘round the world.
"From the data we have, it still seems to be very rare that an asymptomatic person actually transmits onward to a secondary individual,” Dr. Maria Van Kerkhove, of the World Health Organization, said on Monday.
That’s Dr. Maria Van Kerkhove basically telling us that months of government shutdown orders weren't necessary.
On Tuesday, she clarified her message saying that asymptomatic spread is a “really complex question” and much is still unknown.
“We don’t actually have that answer yet,” Dr. Van Kerkhove said on Tuesday. “I was responding to a question at the press conference. I wasn't stating a policy of WHO or anything like that. And in that, I used the phrase very rare. I think that was a misunderstanding to state that asymptomatic transmission globally is very rare. What I was referring to what a subset of studies. These are estimates, and there’s a big range from the different models. Some estimates of around 40 percent of transmission may be due to asymptomatic, but those are from models and so I didn’t include that in my answer yesterday."
Numerous experts worldwide and the Centers for Disease Control and Prevention have warned that people without coronavirus symptoms could still transmit the virus, which explains why the pandemic has been so hard to contain.
At the heart of this issue is whether or not someone without symptoms can transmit the disease. Dr. David Margolius with MetroHealth said the science at this point suggests the answer is yes.
“The reality is, there are a lot of people who could be feeling well that still have the risk of transmitting to others,” said Dr. David Margolius, Internal Medicine, at MetroHealth.
Dr. Van Kerkhove stressed that there's a big difference with asymptomatic spread, where a person never shows symptoms, and a person being "presymptomatic," where they transmit the virus before developing mild symptoms.
She also said her statement only reflected a small set of studies, and there are questions as to whether the same is true globally.
Dr. Margolius said those types of uncertainties only emphasize the importance of lockdown measures.
“Locking down in Cleveland and Ohio prevented what could have been a situation we saw in New York City and Italy,” said Dr. Margolius. “We're all learning so much day by day, week by week. I've certainly said some things in March and April and May which today, I have learned. And each week, I'm learning new things.”
Over the last few months, we've all learned so much about the coronavirus. And there's so much more to learn.
To be safe, doctors continue to urge people to wear masks, socially distance, and wash their hands.
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