This week, a study from the University of Oxford found that the AstraZeneca vaccine can both protect people from serious illness and death, while also reducing the spread of COVID-19.
It's the first study to document this type of evidence, and Houston-area vaccine expert Dr. Peter Hotez is hopeful that other vaccines will be looking to find similar data in its studies.
WATCH: How many vaccines could be in rotation by summer?
"You want a COVID-19 vaccine to do two things," Hotez explained. "One you want it to keep you out of the hospital and the intensive care unit and I think all the vaccines will do that. They are all protecting against serious illness, which is terrific. But in addition, you'd like it to stop virus transmission. By that I mean, that people who get vaccinated and are exposed to the virus don't get the virus and are shedding it without symptoms. I don't think that happens very often but we haven't actually shown that from most of the vaccines."
There is some skepticism from a list of countries, including the United States, claiming there's not enough data yet to submit for FDA approval and the AstraZeneca vaccine is currently only recommended for people 55 years old or younger.
"To stop virus transmission, we need to vaccinate everyone," Hotez said. "We need to vaccinate, 25-year-olds and 35-year-olds and 45-year-olds and 55-year-olds. If you need to use the AstraZeneca vaccine for that group, fine, because what that will do is free up the mRNA vaccine to use for older populations."
Dr. Luis Ostrosky, an infectious disease specialist with UTHealth and UT Physicians said despite the skepticism this is a huge day for the development of vaccines.
"Very exciting results that were released today," Ostrosky said. "They're showing that longer intervals between vaccination, as long as 12 weeks, may be useful in preventing severe and [this] sort of disease that may require hospitalization. [It's] interesting as well, because for the first time, we are getting some data that the vaccine may have some efficacy in preventing asymptomatic disease."
Currently, Moderna and Pfizer are the two vaccines in the U.S. distribution.
The Houston and Harris County Health Department told ABC13 on Wednesday that both have been receiving shipments weekly, but do not know exactly when the shipments will arrive.
The Houston Health Department receives at least 8,000 to 9,000 doses every week and 9,000 doses are delivered weekly to Harris County Health Department.
Galveston Health Department told ABC13 it anticipates getting another shipment next week, but did not receive details on how many doses or when the shipment will arrive.
Hotez anticipates there could be six different vaccines available by the summer, which would help availability and access to the vaccines.
"We're going to need all six if we're serious about vaccinating more than 200 to 250 million people, three-quarters of the U.S. population," Hotez said. "Get whatever you can. It will save your life."
The discovery of new variants and the potential for more in the near future is adding more urgency to improve the U.S. vaccine rollout and to add more vaccines to the supply chain.
"Right now, we have kind of a difficult system, where you need to register and wait and then you get your appointment and somebody needs to take you to those specific places where it's being given," Ostrosky said. "Again, lots of logistics for freezing and refrigeration and timing for getting the vaccines, etc. When we have more vaccines that are sort of more user-friendly, you'll be able to get your vaccine anywhere."
Still have questions about the COVID-19 vaccine? Here are the answers to your most frequently asked questions.
How effective is AstraZeneca?
Data shows the vaccine, AstraZeneca is 90% effective with half of a dose administered first, followed by the full dose.
Does it stop the spread of COVID-19?
This week, a study from the University of Oxford found that the AstraZeneca vaccine can both protect people from serious illness and death, while also reducing the spread of COVID-19. It's the first study to document a vaccine slowing the transmission of the virus.
Who shouldn't take it?
The AstraZeneca vaccine is currently only recommended for people 55 years old or younger.
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