The Omicron variant that is spreading is “almost certainly”  less severe than the virus’s Delta variant, but is highly transmissible, according to Dr. Anthony Fauci.

“Real-world evidence is accumulating rapidly—literally on a daily basis—to allow us to determine increase in cases, possible increase in reproductive number, and the rapid replacement of Delta by Omicron in certain situations,” Fauci said.

Dr. Fauci said that people who have had COVID-19 are more vulnerable to get the Omicron variant.

“There’s a study, again, from South Africa, which showed that there’s an increased propensity for reinfection among people who were previously infected with Beta or Delta to get reinfected more readily with Omicron rather than with Beta or Delta,” Fauci said.

The World Health Organization said Preliminary data suggests that there are increasing rates of hospitalization in South Africa, but this may be due to increasing overall numbers of people becoming infected, rather than a result of specific infection with Omicron.  There is currently no information to suggest that symptoms associated with Omicron are different from those from other variants. 

“It’s too early to be able to determine the precise severity of the disease, but inklings that we are getting — and we must remember these are still in the form of anecdotal, but hopefully in the next few weeks we’ll get a much clearer picture — but it appears that with the cases that are seen we are not seeing a very severe profile of disease,” Fauci said.

It will be several weeks until enough data is collected to determine the severity of the Omicron variant so it is very important to still wear a mask, social distance, and get vaccinated.

The World Health Organization also recommends opening windows to improve ventilation and avoid poorly ventilated or crowded spaces.

The Omicron variant has now been reported in 50 countries and 19 states and the numbers continue to rise, said Dr. Rochelle Walensky, the Director of the Centers for Disease Control and Prevention (CDC). 

According to the CDC, current vaccines are expected to protect against severe illness, hospitalizations, and deaths due to infection with the Omicron variant. However, breakthrough infections in people who are fully vaccinated are likely to occur. With other variants, like Delta, vaccines have remained effective at preventing severe illness, hospitalizations, and death. The recent emergence of Omicron further emphasizes the importance of vaccination and boosters.