The European Medicines Agency (EMA) supports the use of additional COVID-19 vaccine doses, and Spain has already begun administering third doses as part of its vaccination campaign. But... do you know who will receive them?

WHO WILL RECEIVE THE THIRD DOSE?

Several high-risk groups were prioritised to receive a third dose of the COVID-19 vaccine, with the aim of vaccinating around 16 million people in Spain by the end of 2021.

• Adults aged 70 years and over: six months after completing the primary vaccination schedule.

• Adults aged 60–69 years: six months after completing the primary vaccination schedule.

• Healthcare and social care professionals.

• Individuals vaccinated with the single-dose Janssen vaccine.

• Residents of long-term care and nursing homes.

WHO SHOULD RECEIVE AN ADDITIONAL DOSE TO COMPLETE THEIR PRIMARY VACCINATION SCHEDULE?

Certain groups of people with a higher risk of severe COVID-19 were prioritised for an additional vaccine dose, including:

• Recipients of haematopoietic stem cell transplantation (HSCT) or CAR-T therapy within two years of treatment.

• People receiving immunosuppressive therapy.

• Patients with graft-versus-host disease (GVHD).

• Solid organ transplant recipients.

• Patients receiving anti-CD20 therapies.

• Individuals with haematological malignancies or solid organ cancers.

• Patients undergoing certain high-risk immunosuppressive treatments.

• Individuals receiving renal replacement therapy, including haemodialysis or peritoneal dialysis.

• People with cystic fibrosis.

• Individuals with Down syndrome aged 40 years or older.

WHAT IS THE DIFFERENCE BETWEEN AN ADDITIONAL DOSE AND A BOOSTER DOSE?

The doses approved by the Spanish Ministry of Health are additional doses, intended to complete the primary vaccination schedule. They are administered when additional doses are needed to achieve a strong and long-lasting immune response.

A booster dose, on the other hand, is given some time after completion of the primary vaccination schedule to reinforce the immune system's memory and improve protection against the virus. Booster doses are generally administered at least six months after the last vaccine dose.

WHICH VACCINE WILL THESE GROUPS RECEIVE?

The additional dose should be administered using the same mRNA vaccine received during the initial vaccination schedule, namely Pfizer-BioNTech or Moderna.

Booster doses are also administered using mRNA vaccines (Pfizer-BioNTech or Moderna), even if the person's original vaccination schedule was completed with another vaccine, such as AstraZeneca or Janssen.