At this stage, there is no evidence to suggest that earlier booster doses of current COVID-19 vaccines will augment protection against the Omicron variant.
ATAGI will continue to closely monitor the epidemiology and emerging data on the likely impact of vaccination on this variant and update recommendations in the near future.
Background
Omicron was first reported in South Africa on 24 November 2021. The World Health Organization (WHO) declared Omicron to be a COVID-19 variant of concern.
At the current time, very little is known about the characteristics of this variant. Specifically, it is still to be determined whether it is more transmissible, causes more (or less) severe disease, and whether immunity following natural infection or immunisation has an impact on infection and severe disease following exposure to this variant.
Over the coming weeks, more evidence will emerge from laboratory studies, studies of virus transmission, age-specific case-hospitalisation and case-fatality ratios, and studies of breakthrough infections after previous infection and/or vaccination. These studies are underway globally and in Australia.
Vaccine manufacturers have also signalled they are examining the need for and potential development of COVID-19 vaccines that may be more effective against new variants.
A booster dose is currently available to anyone in Australia aged 18 years and over who has completed their primary course of vaccination at least six months ago.
At this stage, there is no evidence to suggest that earlier booster doses of current COVID-19 vaccines will augment protection against the Omicron variant.
ATAGI advises that in certain circumstances, the routine six-month interval for booster doses may be shortened to five months for logistical reasons, for example:
- for patients with a greater risk of severe COVID-19 in outbreak settings;
- if an individual is travelling overseas and will be away when their booster dose is due; or
- in outreach vaccination programs where access is limited.
