PfizerAlbert Bourla, the CEO of the company said Monday that the two doses of its vaccine might not offer strong protection from infection with the omicron Covid type. He also stated that the original shots may have lost some of their effectiveness at preventing hospitalization.

Bourla spoke out at J.P. Morgan’s Healthcare Conference to emphasize the need for an additional shot that can boost protection against omicron.

Bourla stated that the two doses are not sufficient for Omicron. The third dose of current vaccine provides good protection against death and decent protection against hospitalizations.

Bourla claimed that Omicron is more challenging than other variants. Omicron has multiple mutations and can bypass some of the protection offered by Pfizer’s initial two shots.

Bourla explained that the “first thing we lost” was protection from infections. This is what happened with Bourla’s second dosage. But then, two months later what was very strong in hospitalization also fell. This, I believe is what everyone should be concerned about.”

According to the U.K. Health Security Agency, real-world data has shown that 2 vaccines can prevent hospitalizations by 52% in the United Kingdom. This is based on data collected from 25 weeks ago.

According to data from the U.K., two doses of Moderna or Pfizer vaccines only 10% are effective in preventing infection by omicron for 20 weeks.

According to data, a booster dose is effective in preventing symptoms and hospitalization by up to 75%.

Bourla stated that it is not clear how long the booster will protect against Covid. According to the U.K. Health Security Agency, boosters only have a 40%- 50% chance of preventing infection after 10 weeks.

Bourla explained that “the question mark” is whether the protection will last for three doses.

U.S. Centers for Disease Control and Prevention recommends that people suffering from compromised immunity systems get four shots. This includes three booster doses and three primary doses. For people older than 60, Israel now offers fourth doses of Pfizer. Israel has found that four doses of Pfizer increase the protective antibodies five-fold.

Bourla stated to CNBC Monday earlier that Pfizer will make a vaccine targeting the omicron in March. He said however that it is not yet clear if this will be necessary.

Bourla said that CNBC needs to conduct more tests to see if fourth doses are required.