The new form of the inoculation is known as bivalent booster. According to the US FDA website, COVID-19 vaccines include a component of the original virus strain to provide broad protection against COVID-19 and a component of the omicron variant to provide better protection against COVID-19 caused by the omicron variant. These are called bivalent COVID-19 vaccines because they contain these two components. A bivalent COVID-19 vaccine may also be referred to as “updated” COVID-19 vaccine booster dose.
The original data from the first vaccines didn’t test for protection against infection, but was focusing on symptomatic disease, and they protected well against that. It’s still too early to know exactly how the bivalent booster will work in the longer term. So far, the main effect of the bivalent booster compared to the regular inoculation against COVID-19 has been to reduce hospitalization rates rather than rates of infection.