We Know More As To How The Vaccines Work

COVID-19 vaccines teach our immune systems how to recognize and fight the virus that causes COVID-19. It typically takes two weeks after vaccination for the body to build protection (immunity) against the virus that causes COVID-19. That means it is possible a person could still get COVID-19 before or just after vaccination and then get sick because the vaccine did not have enough time to provide protection.  People are considered fully protected two weeks after their second dose of the Pfizer-BioNTech or Moderna COVID-19 vaccine, or two weeks after the single-dose Johnson & Johnson’s Janssen COVID-19 vaccine, CDC has stated.

Studies have shown that several vaccines are highly effective in preventing people getting seriously ill from Covid-19. Now, early results from a survey in the UK suggest two commonly used vaccines — the Pfizer-BioNTech and AstraZeneca shots — can significantly reduce infections.

Twenty-one days after the first vaccine, odds of a new Covid-19 infection were reduced by 65%, according to results from the COVID-19 Infection Survey, coordinated by the University of Oxford, the Office of National Statistics and the Department for Health and Social Care. The largest reductions in odds were seen after a second dose, it said.

The numbers appeared more promising for the prevention of symptomatic infections. The odds of testing positive and self-reporting symptoms were reduced by 90% after the second dose. And vaccination was just as effective in the vulnerable over-75 age group as it was in younger people.

Two studies highlighting the results were posted as pre-prints and have not been peer-reviewed. They analysed 1.6 million test results from nose and throat swabs taken from more than 373,000 people between December and the start of April.

But experts advise people to continue with Covid prevention measures, as some infections will still be transmitted, particularly when large numbers of the population have had just one dose in a two-dose regimen or haven’t been vaccinated at all. Although infections are at a record high, lives are being saved in countries with effective immunization programs.

Although COVID-19 vaccines are effective at keeping you from getting sick, scientists are still learning how well vaccines prevent you from spreading the virus that causes COVID-19 to others, even if you do not have symptoms. Early data show the vaccines do help keep people with no symptoms from spreading COVID-19, but we are learning more as more people get vaccinated.

We’re also still learning how long COVID-19 vaccines protect people. For these reasons, people who have been fully vaccinated against COVID-19 should keep taking precautions in public places, until we know more, like wearing a mask, staying 6 feet apart from others, avoiding crowds and poorly ventilated spaces, and washing your hands often.