And the Pfizer covid vaccine is approved as a booster dose for 16-17-year-olds.
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31 January
- Having a different booster to the primary dose is associated with increased neutralising antibody levels, study finds.
- Pfizer vaccine approved as booster for 16-17-year-olds.
- Son of Omicron rears its head in Australia.
- Antiviral combination therapy recommended for unvaccinated people at risk of severe disease.
Having a different vaccine for the booster dose compared to the primary doses may achieve a stronger immune response, research suggests.
A study published in the New England Journal of Medicine looked at neutralising antibody and T-cell responses in 457 people who received boosters that were either the same as their primary dose or a different vaccine.
Overall, boosters increased levels of neutralising antibodies 4-73-fold higher than for double-vaccination. Among those who were boosted with the same vaccine as their primary dose neutralising antibody titres increased 4-20-fold, but among those boosted with a different vaccine, the titres increased by a factor of six to 73.
However there were no significant differences in adverse events between any of the boosters, regardless of the primary vaccine used.
The Pfizer covid vaccine is now approved for use as a booster dose in people aged 16 and 17 years but ATAGI is yet to make a recommendation on boosters in this age group.
The Therapeutic Goods Administration has granted provisional approval for Pfizer boosters, following in the footsteps of health authorities in the US, UK and Israel.
Omicron has generated its first significant offspring in the form of the variant lineage BA.2, which has now been detected around Australia and has become the dominant strain in countries such as Denmark.
Despite some key mutations that could affect how antibodies bind to the virus, the variant is not yet listed as a variant of concern and experts say it’s too early to know whether it poses a significant threat.
Most of the samples of this variant have come from Denmark, the UK and India. Early patterns suggest it may be more transmissible than its parent variant, but so far there is no evidence of increased severity.
