How soon is the Covid vaccine effective?


The Pfizer BioNtech vaccine was approved in early December, with the Moderna and AstraZeneca jabs following suit some weeks later. The Pfizer jab uses a weakened, harmless version of a common virus which was found to be giving a cold to chimpanzees. The virus in question has previously been used to produce vaccines against the flu, Zika virus and Middle Eastern respiratory syndrome (MERS).

Both the Pfizer and Moderna jabs are messenger RNA vaccines (MRNA), which differs from a conventional vaccine in that it only uses the disease’s genetic code instead of a weakened form.

The vaccine is injected into the body, entering cells and instructing them to create antigens.

The antigens are then recognised by the immune system in order to prepare itself to fight off the virus.

Because no actual virus is needed to produce this vaccine, the production time can be much quicker, which explains why they were developed in under one year while others can take up to a decade.

READ MORE: Mark Drakeford blasted by BBC host over Wales vaccination plan

How soon is the Covid vaccine effective?

In general, protection from the virus starts seven to 10 days after the day you were immunised.

The Pfizer/BioNtech and Moderna vaccines need to be given out in two doses, and immunity starts seven to ten days after the second dose is administered.

One dose vaccines are thought to take about 29 days to prepare your body to build immunity against Covid-19.

Infectious disease doctor at Yale Medicine Onyema Ogbuagu said: “When you get a vaccine, usually there is a lag time between when you get the vaccine and when you are protected against the virus.

While that’s undoubtedly impressive considering the short timeframe in which it has been created, it still leaves five percent of people who won’t become immune to Covid.

Dr Ogbuagu said: “That still means hundreds of thousands, depending on what [population] scale you’re looking at, could receive the vaccine and not be protected.”

If and when you receive the second dose also affects how long it will take for you to be protected.

Vaccine researchers and health experts recommend getting it about three to four weeks following the first dose, depending on which vaccine you are given.

If you skip a dose, you won’t be fully protected and could still be at significant risk of contracting the Covid virus.

On the other side of the coin, however, some people may be fully protected after just one dose, but regardless, everyone should plan to have the full course.

Furthermore, different factors, including age, influence how quickly a person’s immune system can respond to the jab.

Vaccination doesn’t mean you can flout the rules, and even if you’ve been immunised you are urged to keep sticking to social distancing and other protective measures which ultimately, is the safest course of action while the country continues to battle the pandemic.




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