Here's why AstraZeneca's coronavirus vaccine has an edge over Moderna's and Pfizer's

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Vaccine news has been such a rollercoaster that it’s hard to stay excited about constantly changing developments. But new research conducted in the U.K. suggests that a vaccine developed as a collaboration between the University of Oxford and pharmaceutical company AstraZeneca may have one very important difference from the vaccines currently available to us: It could significantly reduce transmission of COVID-19 . Here’s what we know about how AstraZeneca’s vaccine could curb the pandemic.

The study, which was conducted at Oxford University in London, was released this morning as a pre-print in medical journal The Lancet. Researchers followed 17,000 individuals, some of whom received AstraZeneca’s COVID-19 vaccine and some of whom got a placebo for over 12 weeks. Yes, that is standard operating procedure for vaccine trials, but this study did something that none of the other vaccine research trials have done, CBS reported. Instead of only testing participants who showed symptoms of COVID-19 for infection, they tested every participant on a weekly basis.

In people who had been vaccinated, scientists found that 67% fewer of them tested positive for COVID-19 than those who received the placebo. What that means is that 67% of participants not only didn’t have symptoms, they had no trace of the virus and therefore could not transmit it to anyone else.

This is a really big deal because one of the problems we’ve seen with the vaccines is that, while they protect the people who get them, they don’t prevent those same people from asymptomatically spreading the disease, which is thought to be one of the biggest drivers of the pandemic.

Also, the study supports the idea of giving a longer gap between doses, at least with this particular vaccine. According to the research, the first shot of the vaccine stayed 72% effective for up to 90 days, and leaving at least three months between the shots boosted its effectiveness to over 82%. That’s not as high as some of the other vaccines — which boast 90-95% efficacy — but, personally, I will take a 13% increase in personal risk if it means that I am less likely to spread the virus to others. AstraZeneca’s vaccine has been approved for emergency use in the U.K. and is in Phase 3 trials in the U.S., and the company is currently updating it so that it will be effective against the new variants.

This study could be really really good news because — if nothing else — it shows that we have vaccine choices. Unfortunately, it hasn’t been peer reviewed so — as usual — we need to temper our enthusiasm, but health experts say that this research should give us hope even if not all the findings turn out to be perfect. When asked about the AstraZeneca vaccine study, Anthony Fauci said, “If that’s true, it’s good news. We’re going to have multiple candidates in the mix,” NBC reported. Yes. I have all my fingers and toes crossed that this vaccine is the one, but if it’s not, at least it shows that we have choices.