Experts have said that the extra dose will help the most vulnerable stay protected against severe Covid-19 symptoms.
The Joint Committee on Vaccination and Immunisation said that vaccinating these groups was only a "precautionary" measure and did not mean there was any increase in danger to their wellbeing.
Until today (21 March) only people with weakened immune systems had been eligible for a second booster dose.
Below is everything you need to know about the fourth dose, or second booster, and who is eligible.
Who is eligible for a fourth dose of the vaccine?
Those now being offered a second booster from today are:
adults aged 75 years and over
residents in a care home for older adults
individuals aged 12 years and over who are immunosuppressed
What type of vaccine is the fourth booster dose?
Adults will be offered a Pfizer or Moderna vaccine, while children aged 12 to 18 will receive Pfizer.
The vaccine must be administered at least six months after the first booster dose.
Where can I get the fourth dose in Leeds?
If you're eligible, a GP or your hospital specialist should contact you to let you know you can get a 4th dose.
You may also get a letter from the NHS advising that you may be eligible and to discuss this with your doctor.
You'll usually get vaccinated at your local hospital or a local NHS service such as a GP surgery.
A full list of sites in Leeds offering vaccinations is available on the NHS website.
Can I book my fourth dose online?
If you're aged 12 or over, you can also book your 3rd dose or booster (4th dose) appointment online.You'll need to bring with you either:
* a letter from your GP or hospital specialist inviting you for a 3rd dose or booster (4th dose)
* a hospital letter that describes the condition or treatment that caused you to have a severely weakened immune system at the time of your 1st or 2nd dose
* a prescription or a medicine box with your name and the date showing when the medicine was prescribed – this must show that you had a severely weakened immune system at the time of your 1st or 2nd dose
If you think you’re eligible for a 3rd dose or booster (4th dose) but you do not have a suitable letter, prescription or medicine box, you may still be able to get your vaccination.
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