CDC Approach To Breakthrough Infections Sparks Concerns

CDC Approach To Breakthrough Infections Sparks Concerns

8:14pm May 27, 2021

<<INTRO>> The Centers for Disease Control and Prevention has stopped tracking every case that occurs when a COVID-19 vaccine fails to protect someone. Instead, the CDC is focusing on people who get very sick or die. But critics say that's not enough. NPR Health Correspondent Rob Stein has the story.

<<SCRIPT>> The COVID-19 vaccines are very effective. But they're not perfect. People can still sometimes get infected. It's rare. But the CDC says more than 10,000 fully vaccinated people have still caught the virus. So the CDC's been tracking these so-called breakthrough infections. To try to find out more about them. But the CDC recently decided to concentrate on people who get so sick they end up in the hospital or die.

Here's CDC Director Rochelle Walensky at a recent briefing:

<<You know these vaccines were studied to prevent severe illness, hospitalization and deaths. And as we look at these breakthrough infections these are the ones we're most concerned about.>> [Duration: 00:08]

Because in the other cases, people don't get very sick or don't even know they've been infected.

<<Before we started only studying breakthrough infections in only hospitalized patients, we were studying all breakthrough infections. What we were starting to find is a large portion of them were fully asymptomatic and in fact when we went to study them and sequence them there was inadequate virus to even do so.>> [Duration: 00:17]

And if scientists can't sequence genes from the virus, there's little chance these people are contagious... and there's not much researchers can learn by studying them.

But some think the CDC should be casting a much wider net.

<<Just looking at hospitalizations or cases from people who die is really keeping I believe blindfolds on your eyes and not fully understanding what's happening with this virus.>> [Duration: 00:12]

Rick Bright is a former federal health official who's now with the Rockefeller Foundation.

<<It puts us at a disadvantage of better understanding this virus and how to end the pandemic.>> [Duration: 00:05]

Because... Bright says... investigating the full spectrum of breakthrough infections could provide crucial information about all sorts of things. Are some vaccines working better than others? Are breakthroughs happening more in some people than others? Are the variants breaking through the vaccines more than they expected? Have more dangerous new mutants evolved?

<<These variants are spreading and if you're just looking at the small percentage then you're really missing the big picture. You're missing the big story of where the virus is and how it's changing.>> [Duration: 00:10]

Others agree. Saad Omer is a vaccine researcher at Yale. At the very least, Omer thinks the CDC should be randomly sequencing virus from all breakthroughs.

<<If there is a new variant or there is a change in frequency in a variant you might want to find out earlier than wait for it to appear in severe and hospitalized cases. That gives you the ability to be ahead of the outbreak rather than follow it.>> [Duration: 00:20]

<<Others agree. Dr. Alexander Greninger is studying vaccine breakthroughs at the University of Washington.

<<We want to understand: All right, when these breakthrough infections do occur you know what populations are they occurring in so we can potentially have extra protection, you know develop laboratory tests that allow us to predict this, develop epidemiological sort of profiles of people that this might happen in. And also how to make our vaccines as good as possible, right? We got these great vaccines, but how can we do better?22>>

Now, CDC officials say the agency isn't ignoring other breakthroughs entirely. The agency's studying how well the vaccines are working in specific groups like health care workers and nursing homes.

Doctor Marc Fisher is leading the CDC's vaccine breakthrough team.

<<CDC will continue to look at vaccine effectiveness in all populations including people with mild infections and that's being done through special studies, vaccine effectiveness studies and other monitoring in different populations and settings.>> [Duration: 00:16]

In addition, some individual states and independent scientists are investigating all breakthrough infections more closely.

Doctor Carlos Del Rio is an infectious disease researcher at Emory University. He agrees with the CDC's strategy.

<<I just think from a strategy and prioritizing standpoint they are doing the right thing. They're they're really focusing on on what matters.>> [Duration: 00:07]

But critics still worry that CDC's approach could leave the country vulnerable to getting blind-sided once again by whatever new threats the virus may pose.

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