Wis. (WLAX/WEUX) – Pfizer is tweaking its COVID-19 booster for infants and young children.

The pharmaceutical company asked the FDA Monday to replace its third vaccine dose with an updated one that targets two omicron variants, B-A-4 and B-A-5.

Kids under five would still receive two doses of the original Pfizer vaccine before receiving the updated third shot. According to the CDC, fewer than five percent of children younger than five have been fully vaccinated against COVID.

So far, this winter season has been particularly rough for young kids with RSV cases surging, causing hospitals to quickly fill up. While no vaccine exists for RSV, medical professionals are reminding the public to get their annual flu shot and keep up to date with their COVID boosters.