Transcript for What does the Johnson & Johnson vaccine pause mean in the fight against COVID-19?
Reporter: It's the covid vaccine that promises strong protection with a single dose, an important tool for public health officials around the world. But tonight the fda is telling everyone to hold off using the Johnson & Johnson vaccine. A very small number of women have come down with an extremely rare blood clot after getting the shot. This is a really rare event. If you look at what we know so far there have been 6 out of the 6.85 million doses, which is less than 1 in 1 million. Reporter: All 6 women between 18 and 48 years old. They got sick six to 13 days after getting vaccinated. The clots formed in veins of the sinus and prevented blood from draining out of the brain. One woman died. Another is in critical condition. There's no evidence showing the vaccine caused the condition, and to be super clear, your chances of getting struck by lightning are nearly twice as high, 1 in 500,000. With 6 patients that developed the rare type of blood clot out of 7 million Johnson & Johnson shots given, this is far less than the number of blood clots and even deaths we see among Americans who become infected with the covid-19 virus. So the pause not only allows us to take a look at cases and learn more, it is also a signal out there to help the physicians. Reporter: Health officials say these rare immune responses have only been seen in viral vector vaccines. Johnson & Johnson is one, astrazeneca is another. Pfizer and modern use another. The federal government put a pause on using the shot at mass vaccination sites and the states followed. The nation's governors are beyond frustrated. In a phone call with the white house, they question the wisdom of putting a hold on a vaccine over such a small number of The ability for governors to re-instill confidence after something like this is 100 times harder than putting the pause on in the first place. Reporter: Today pfizer announced they now expect to deliver some 300 million doses, about two weeks ahead of schedule. Moderna is announcing they're on track to deliver their 300 million doses by July. For "Nightline," I'm Steve osunsami. Joining me is ABC news chief medical correspondent, Dr. Jen Ashton. Doc, first question, help us put this in perspective. We know the clotting issue is very rare, but it's concerning. If you receive the j&j vaccine, are there specific symptoms people should be aware of? And when is it time to call your doctor? First thing that people need to remember, we have a saying in medicine, an increased risk of a rare event is still a rare event. So people need to keep that in mind. However, headache, abdominal pain, leg pain, all of those things, if you've been within three weeks of the j&j vaccine, should prompt a phone call to your physician or health care provider, or if very severe, the emergency room. We've also heard governors now complaining about the pause that it will hurt efforts to build confidence in these vaccines. What are your thoughts on that? This is our public health system, our science, and our medicine at work. It shows people very clearly that no safety corners will be cut. I think people need to be reassured that even when there's no definitive link or causality, that no chances will be taken when it comes to people's Doc, to follow that point, this can further erode trust in the overall vaccine efforts, especially in marginalized communities. How do you address that, people already anxious before this news? First of acknowledge it's appropriate to have concern. It's normal and understandable to have questions and even anxiety. We have to stay with the facts and the facts are that these vaccines are safe and effective, and if there is a safety concern, our fda, our CDC, will revoke them. Here at ABC news, you're our Dr. Fouchl Chee, we trust you above all others. Anything concern you at this or do you feel things are moving along well? In terms of the vaccine rollout, things are picking up. We need to get more people vaccinated for sure. It's a race against the vaccine versus the virus and the variants. And that is neck and neck right now. That's a race that we cannot afford to lose. There's also growing concern over the different emerging variants. Some states seeing a surge in infection and hospitalization rates. How will this impact vaccination efforts, do you think? Well, I've spoken to Dr. Anthony Fauci about this many times and he's been crystal clear. The way to slow the variants is to stop the spread of the virus in the community. And one important way that we will do that is with rapid vaccination of our population. But Byron, we cannot lose sight. It's not just about what goes on in this country, it's about the vaccination campaign world wide. It doesn't help us if we're vaccinated but other countries around the world are not. This is a global effort. Dr. Jen Ashton, thank you as always, good to see you. You bet, my friend.
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