Australia’s Therapeutic Goods Administration (TGA) has recently approved a new COVID booster. The shot was developed by Pfizer and targets the JN.1 sub-variant of Omicron.
This is now the fifth iteration of the COVID vaccines, which have been updated regularly to keep up with the rapidly evolving virus, SARS-CoV-2. But nearly five years into the pandemic, you may be wondering, why do we need yet another type of COVID booster? And do we still need to be getting boosters at all? Here’s what to consider. Targeting the spike protein Pfizer’s JN.
1 booster (and Moderna’s, though the TGA has not approved this one at this stage) is based on mRNA technology. This technology instructs our cells to produce a specific protein – in this case SARS-CoV-2’s spike, a protein on the surface of the virus that allows it to attach to our cells. This helps the immune system produce antibodies that recognise the spike protein and interfere with the virus getting into our cells.
In response to our strengthened immune responses from vaccinations and previous infections (called immune pressure), SARS-CoV-2 has continued to evolve over the course of the pandemic, modifying the shape of its spike protein so our antibodies become less effective. Most recently we’ve faced a soup of Omicron sub-variants, including JN.1.
Since JN.1 was first detected in August 2023 , this Omicron sub-variant has spawned a variety of further sub-variants, such as KP.2 (known as FLiRT), KP.
3 ( known as FLuQE ) a.