Transcript for Reports of vaccine demand slowing down, continued vaccine hesitancy
and the concern growing when it comes to coronavirus here in the U.S. The demand for vaccines slowing down. Thousands of appointments apparently going ignored across the country. And they want to get the word out that there is available vaccine. This all comes after the CDC imposed that temporary pause on the Johnson & Johnson vaccine. Tonight, European regulators now supporting the one-shot vaccine as long as there is a warning that goes with it, saying that the benefits do outweigh the the CDC saying it could lift the pause here later this week. We know there's going to be another meeting. What they're reluctant tonight, what we're learning tonight. Here's ABC's Marcus Moore. Reporter: Growing reports tat demand for vaccine is slowing down, as thousands of appointments go unfilled across the country. How critical is it that people get vaccinated? It is absolutely critical, we are in a race against the virus, and against time to reach herd immunity before the virus mutates into something that can defeat our vaccines. Reporter: This site in Dallas can do 12,000 vaccinations a day. But on some days, they're doing as few as 4,000. 44% of counties in this country are battling high community spread of kroefts, coronavirus, but many rural areas are seeing lower turnout for the vaccine. Just like many other places across the United States, rural populations are just not coming out to get vaccinated. Reporter: And vaccine hesitancy is higher in underserved communities hit hardest by the virus. I'm just waiting more or less to see what is going on and then I can decide whether or not I want to take it. Reporter: A recent poll revealing a political divide, too. 45% of Republicans said they do not plan to get a covid-19 vaccine right now, compared to 27% of Americans overall. Doctor and Republican congressman Andy Harris giving shots in his home district in Maryland. You should be getting the vaccine because the benefits outweigh the risks, and we need to make sure we are protecting our most vulnerable people in the United States. Reporter: David, back to that news on the Johnson & Johnson vaccine. While European officials are recommending a warning, back here in the U.S., the CDC advisory panel is expected to meet again on Friday. David? All right, Marcus Moore tonight with us, as well. Thank you.
This transcript has been automatically generated and may not be 100% accurate.