Maternal COVID-19 Vaccination Lowers risk of infection by omicron varient among infants: JAMA

In a recent population-based cohort study Orlanda Goh and colleagues unveiled crucial insights into the impact of maternal mRNA vaccination on the vulnerability of infants aged 6 months or younger to the Omicron variant, including the emerging XBB strain. The findings were published in the Journal of American Medical Association.

The study spanned from January 1, 2022, to March 31, 2023 and utilized Singapore's national dataset. It focused on infants born at more than 32 weeks of gestation. Out of the 21,609 infants studied, 33.7% had at least one parent with confirmed SARS-CoV-2 infection before the age of 7 months.

The findings brought out the importance of vaccination timing during pregnancy. Infants born to mothers who received the mRNA SARS-CoV-2 vaccine during pregnancy exhibited a significantly lower risk of Omicron infection, with an estimated vaccine effectiveness (VE) of 41.5%. Intriguingly, those whose mothers were vaccinated prior to pregnancy did not show a lower risk, with an estimated VE of 15.4%.

The study highlighted a distinctive advantage in the face of the Omicron XBB variant. Infants born to mothers vaccinated with the third (booster) dose during pregnancy showed a substantial reduction in the risk of XBB infection, with an estimated VE of 76.7%.

The study underscore the critical role of maternal mRNA vaccination in mitigating the risk of SARS-CoV-2 infection among newborns, particularly concerning the Omicron variant and its emerging strains. The research provides valuable inputs for public health strategies, emphasizing the potential benefits of antenatal vaccination to safeguard the vulnerable infant population.

While these results offer promising indications, they also highlight the necessity for continued research and vigilant monitoring. The study prompts some important discussion on the optimal timing of maternal vaccination to ensure the highest level of protection for infants, especially in the evolving landscape of SARS-CoV-2 variants.

Source:

Goh, O., Pang, D., Tan, J., Lye, D., Chong, C. Y., Ong, B., Tan, K. B., & Yung, C. F. (2023). mRNA SARS-CoV-2 Vaccination Before vs During Pregnancy and Omicron Infection Among Infants. In JAMA Network Open (Vol. 6, Issue 11, p. e2342475). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2023.42475