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What do you need to know about the Covid-19 booster jab?

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Why do we need another dose of the Covid-19 vaccine, who should get it and how will our bodies react? Dr Annette Alaeus, Livi’s Head of Infectious Diseases, answers your questions

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With the Covid-19 vaccine rollout largely a success across Europe, experts are now recommending a third booster dose to protect us all.

Reassuringly, the idea behind booster jabs has been around for a long time. We also get boosters for diseases like tetanus and polio to keep our immunity strong. Here, we answer your biggest questions about the booster.

Why should I get the booster?

Immunity against Covid-19 gradually decreases over time. ‘The more time passes since you were vaccinated or infected with the virus, the higher your risk of catching Covid-19,’ says Dr Annette Alaeus, Livi’s Head of Infectious Diseases.

‘Over time, our levels of neutralising antibodies against Covid-19 decrease. The decline is especially sharp in older people and those with underlying conditions.’

A Swedish study, which evaluated data from over 800,000 fully vaccinated and unvaccinated people, found that protection against severe Covid-19 infections drops significantly over time (from 89% initially to 42% after 6 months). The risk of breakthrough infections also increases over time.

Getting a third coronavirus vaccine reactivates the body’s immune response and improves the effectiveness of the protection. According to an Israelian study, which included more than 700,000 vaccinated people, having a booster vaccine provides good protection against both being infected in the first place and having a severe case if you do get infected.

The booster vaccine can also reduce your viral load and how infectious you are. If you have Covid-19, your risk of infecting the people around you is lower if you’ve been vaccinated. That’s why vaccines are a crucial way to protect vulnerable groups of people.

Who should get the booster?

The NHS recommends having a booster if you’ve had your second dose of the Covid-19 vaccine at least 3 months ago and you’re in one of these groups:

  • You’re aged 18 or over
  • You’re aged 16 or over and you’ve got a health condition that makes you vulnerable to severe Covid-19
  • You’re a frontline health or social care worker
  • You live or work in a care home
  • You’re aged 16 or over and are a caretaker for a vulnerable person
  • You’re aged 16 or over and live with someone who has a weakened immune system (such as someone who has HIV, has had a transplant or is having certain treatments for cancer, lupus or rheumatoid arthritis)

If you’re pregnant and in one of the eligible groups, you can also get a booster dose.

If you received a Johnson & Johnson vaccine originally, you should get a booster jab with an mRNA vaccine. People who’ve had this vaccine may be more prone to breakthrough Covid-19 infections.

Do boosters work against the Omicron variant?

While we still have a lot of unanswered questions about Omicron, experts agree that a booster shot should give you added protection against the variant. ‘There’s data that suggests the vaccine might be a little less effective against Omicron, but it’s still working,’ assures Dr Alaeus.

It helps to remember that the vaccines were more effective than expected in the first place. ‘The vaccines we started with have shown excellent – even amazing – protection. Even if there is a slight decline in protection, the booster will still protect you against serious disease,’ says Dr Alaeus.

Will there be a new vaccine developed against Omicron?

‘While we have the ability to create mRNA vaccines against specific variants, it takes time to produce and manufacture them,’ says Dr Alaeus.

‘There are discussions around producing a “cocktail” vaccine that targets multiple variants, including Omicron. But it’s too soon to know if we’ll need it.’ For now, the booster we have available is still the best approach.

Do I need the booster to be considered fully vaccinated?

If you’ve had 2 vaccinations, you’re still considered fully vaccinated. But this may soon change, and your vaccination status may expire after a certain period if you don’t have a booster.

Which vaccine will I get?

Most people will receive the mRNA Pfizer/BioNTech or Moderna vaccines for their booster jabs. Even if you had a vector vaccine (AstraZeneca or Johnson & Johnson), you may be offered Pfizer/BioNTech or Moderna for your third vaccine. The AstraZeneca vaccine may be offered to some people who can’t have the mRNA vaccines.

Can the booster vaccine cause side effects?

A booster dose may cause side effects, just like the first or second dose. ‘If you do get any side effects, they’re likely to be milder or the same as with your first doses,’ says Dr Alaeus.

In the US, many people have already been vaccinated 3 times. According to the FDA, the most common reactions to the vaccine are:

  • Pain at the injection site
  • Fatigue
  • Muscle pain
  • Headaches
  • Fever

These symptoms usually last only 1-2 days. They’re part of the body’s normal immune response and can be a sign that the vaccine is working.

Symptoms that happen 4-16 days after you’ve been vaccinated are considered vaccine side effects. If you experience any side effects, seek medical assistance and report them through the YellowCard scheme.

Where can I get the third booster vaccine?

You can get your third coronavirus vaccination from your GP, a mobile vaccination team or at a vaccination centre. As demand for booster vaccines is already high, it’s worth making an appointment as soon as you can.

Where can I find out more?

You can find up-to-date and reliable information on the booster vaccine from the NHS website.

While there’s still a lot we don’t know about the pandemic, we do know that getting your booster is one of the most important ways to protect yourself. ‘When it becomes available to you, you should get it,’ urges Dr Alaeus.

This article has been medically approved by Dr Annette Alaeus, Livi’s Head of Infectious Diseases.

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