Chinese study suggests Omicron reinfection risk

New research suggests that individuals who have previously been infected with the Omicron variant of Covid-19 may still be at risk of reinfection by newly mutated sub-variants. The study emphasizes the limited effectiveness of vaccination boosters targeting the original Omicron variant. These emerging sub-variants, such as BA-4, BA-5, and BA-2-12-1, exhibit greater resistance to immunity and transmissibility. However, the incidence rates attributed to these strains are lower compared to the widespread Omicron outbreaks of 2021. Experts warn that the development of broad-spectrum vaccines capable of combating multiple Omicron variants remains challenging. Additionally, many monoclonal antibody treatments have weakened efficacy against these sub-variants due to recent mutations.

Medriva Newsroom
New Update



According to recent research published in the Nature journal, people who were infected with the variant of the Covid-19 omicron virus are susceptible to re-infection by subsequently mutated sub-variants, especially BA-4, BA-5, and the BA-2-12-1 variants.


The researchers cautioned that vaccination boosters centered on the original omicron variant might not provide broad spectrum safety against the emerging Omicron sub-variants.

The study revealed that the immunity gained by getting infected with the earlier variant of omicron does not deliver sufficient safety against the newer strains, debunking the hotly debated notion that the omicron version is a "Natural Vaccine" with minor symptoms and generally people should try and become infected in order to obtain immunity against newer strains of the virus.

BA-4, BA-5, and the BA-2-12-1 are novel strains of Omicron that outperform their predecessors in terms of immunity resistance and transmissibility. They have lately become the prevailing strain in the USA, South Africa, and a few European nations, but the overall incidence rates ascribed to these strains are less than the surge in Omicron outbreaks that swept the world towards the end of 2021.


Sunney Xie Xiaoliang, a biochemical professor at the Peking University, who is also one of the scientists associated with the study, informed that BA-4, BA-5, and BA-2.12.1 all have a mutation known as L-452, while BA-4 and BA-5 have an added mutation known as F-486V.

According to him, these mutations were critical in improving these sub-variants capability to evade antibodies from the primary Omicron strain, resulting in breakthrough infection.

According to Xie, booster vaccines which give broad spectrum defense against a variety of Omicron variants are still needed. This will necessitate advances in mRNA or protein vaccines, but building a vast-range vaccine is relatively hard, he warned.

In terms of treatments, Xie stated that, except for Evusheld and Bebtelovimab, most monoclonal anti-body medicines have lost their potency against the sub-variants of Omicron due to recent mutations.

Chat with Dr. Medriva !