Booster choices

With national booster coverage at around 60%, there remains a significant number of patients now due for their COVID-19 vaccine boosters. Adults now face a choice of 4 different vaccines in this country.

1. Pfizer Comirnaty has been the most requested vaccine locally, and probably around the world. By design the dosage strikes more of a balance between efficacy and adverse symptoms, when compared to the similar mRNA-based Moderna Spikevax. Patients who had 2 doses of this vaccine should mostly opt for a third dose of the same, to reduce their chance of adverse effects.

2. In contrast Moderna Spikevax aimed for the highest possible efficacy from inception. Data indicates it probably has the highest efficacy and durability of all vaccines already in use. Patients who had 2 doses of non-mRNA vaccines should consider this booster, since a switch in vaccine entails an increased chance of adverse effects regardless; but also to compensate for the shortfall in efficacy of the first doses.

3. Novavax Nuvaxovid has just been approved for use as a booster, but less recommended. Data indicates a significant boost in protection, but less than both of the mRNA competitors. Due to the repeated delays in rollout there remains a relative paucity of data.

4. Those seeking an alternative to mRNA technology may be tempted to have a third dose of AstraZeneca Vaxzevria as a booster. This is allowed but not recommended, as the viral vector will be attacked by the immune system before being able to unload the DNA cargo, resulting in only a slight boost in protection.

Collins GP now maintains mostly Pfizer Comirnaty, and a residual stock of AstraZeneca Vaxzevria. The other choices are available from the government’s vaccine hubs.