Just one dose of the Pfizer and BioNTech’s COVID-19 vaccine reduces the number of asymptomatic infections. It can also reduce transmissions to a great extent, report some UK researchers.
Scientists analyzed the thousands of results of the tests being carried as part of the screening of healthcare professionals in Cambridge.
They found out that a single dose of Pfizer-BioNTech vaccine reduced the positive tests of asymptomatic staff among them. They separated the results of those vaccinated and those who were not.
A Single Dose of Pfizer-BioNTech Vaccine Reduces Transmission, Study Finds
The team of scientists discovered that 0.80% tested positive for the infection in the unvaccinated group. This when compared with the 0.37% positivity rate after less than 12 days of vaccination. As you know, this is the time when the effectiveness of the vaccine cannot be predicted. After 12 or more days, it became 0.20%.
Other scientists are yet to review the results. But these got published on an online platform.
The study shows a four-fold reduction in the risk of asymptomatic infection in health workers after more than 12 days of vaccination. It implies that the vaccine provides up to 75% protection, they said. The extent of asymptomatic infection too was reduced to half before 12 days of vaccination.
Two other studies, published in the British medical journal too showed the same result. According to it, a single dose of the Pfizer vaccine will protect those who had COVID 19 from getting it again.
And to add up to the excitement, the US Food and Drug Administration announced that they can keep the Pfizer vaccine in a regular refrigerator for 14 days. Originally, the vaccine required to be stored at ultra-cold temperatures.
The vaccine manufacturers had applied for approval after it concluded a study that it is safe even when stored in a regular refrigerator. This, according to experts makes the vaccine less expensive.
And it will be easier to store and distribute the same. Studies show that the vaccine works well for two weeks when stored in a -25°C to -15°C temperature. Moderna too revealed the same results for its two-dose vaccine against the B.1.35.1 virus variant.
Experts are of the view that more studies are required with regard to asymptomatic transmission. Still, the study is a step forward. Even Canadian researchers attest to these observations.
They, in a recent letter, had recommended that the country can delay the second dose. According to them, the first dose itself provides sufficient protection.
There are also experts who believe that this is not the end of it. Coronavirus always surprises scientists with its ability to outpace the defense mechanism the world has prepared for it.
Pfizer also announced that alternative doses are yet to be evaluated. A decision in this regard will depend on the health officials. Another issue that has surfaced is the objection that the people who took part in the trials were relatively healthy and young.
Britain has been vaccinating its people using both the Pfizer dose and the one from AstraZeneca from last December. According to scientists, this is good news. The Pfizer shot not only reduces infection, but also minimizes its transmission to others. But they have to know that the vaccine does not offer complete protection to everyone.
Israel, the leader in vaccinating its people, published the most significant real-world data about the shot. They say that the two doses of Pfizer vaccination cuts transmission of the infection to 5%. The same applies for severe infections, they said.
The finding is a landmark for a nation desperate to end the lockdown and to reopen its economy.