BA.4 and BA.5 subvariants of Omicron warrants 4th DoseBA.4 and BA.5 subvariants of Omicron warrants 4th Dose

Australia is now facing a surge in cases of the newer BA.4 and BA.5 Omicron subvariants of Covid and it needs to be grappled with fast. As part of the health experts’ strategy, the waning effectiveness of the Covid shots over time will soon get a boost, with a 4th dose. At present some limited categories of Australians under the age of 65 are eligible.

At the moment, ATAGI recommends an additional booster dose of COVID-19 vaccine to increase vaccine protection for selected population groups (see Table 1) who are at greatest risk of severe illness from COVID-19 and who have received their primary vaccination and first booster dose. These groups are:

  • Adults aged 65 years and older
  • Residents of aged care or disability care facilities
  • People aged 16 years and older with severe immunocompromise (as defined in the  ATAGI statement on the use of a 3rd primary dose of COVID-19 vaccine in individuals who are severely immunocompromised)
  • Aboriginal and Torres Strait Islander people aged 50 years and older.

The additional winter booster dose can be given from 4 months or longer after the person has received their first booster dose, or from 3 months after a confirmed SARS-CoV-2 infection, if infection occurred since the person’s first COVID-19 booster dose.

The additional winter booster dose is now available to coincide with the 2022 influenza vaccination program.

Influenza vaccine can be co-administered with the additional booster dose of COVID-19 vaccine. However, if a person is not yet eligible for their additional booster dose, influenza vaccine could be given ahead of the additional booster dose.

Comirnaty (Pfizer) or Spikevax (Moderna) are the preferred vaccines for COVID-19 booster doses including the additional winter booster dose. Vaxzevria (AstraZeneca) can be used when an mRNA vaccine is contraindicated or a person declines vaccination with an mRNA vaccine. Nuvaxovid (Novavax) can be used if no other COVID-19 vaccine is considered suitable for that person.

Also read: COVID numbers on the fall in Victoria

But that advice is likely to be updated soon.

People over the age of 30 will be able to get a 4th dose of coronavirus vaccine under the updated vaccination strategy being formulated while the recommendation will be only for Australians over 50.

The Australian Technical Advisory Group on Immunisation (ATAGI) may recommend the change to federal Health Minister Mark Butler any time now.

The Therapeutic Goods Administration (TGA) is likely to approve Moderna’s COVID-19 vaccine for children aged six months to six years.

Currently children under the age of five in Australia cannot be vaccinated although in the US the Moderna vaccine and a Pfizer vaccine have been allowed to be administered in that age group.

Pfizer’s new vaccine known as a “monovalent” contains only antigens for the Omicron variant. It also has a vaccine called “bivalent”, with antigens for both Omicron and the original COVID-19 strain.

The TGA, after granting a provisional determination for its bivalent vaccine in late April is considering data from Moderna’s Omicron-specific vaccine.

By Singh