According to preliminary findings from Oxford University, just one dose of the AstraZeneca COVID-19 vaccine appears to prevent serious COVID-19 disease. It also reduces transmission of the coronavirus. The researchers found that no patients experienced severe COVID-19 or required hospitalization three weeks after receiving a first dose of that particular vaccine. It also cut virus transmission by two-thirds. And the protection appeared to last up to three months after one dose. Now, it’s not clear if these same results will be found with the Pfizer or Moderna vaccines used here in the U.S. But if these findings hold up, it might justify the British government’s controversial decision to delay the second shot for up to 12 weeks so more people could be given a first dose.