RELATED: Don’t Get a Booster Shot Without Doing This First, Experts Warn. In a statement released on Nov. 29, the CDC announced that it was strengthening its recommendations for COVID boosters, saying that anyone who is 18 or older should receive the extra shot six months after their initial Pfizer or Moderna vaccines or two months after their initial Johnson & Johnson vaccine. This is a major change to the previous guidelines, which stipulated that adults “may” get the booster while people aged 50 or older or living in long-term care facilities “should” get the supplemental shot. “Today, CDC is strengthening its recommendation on booster doses for individuals who are 18 years and older,” CDC Director Rochelle Walensky, MD, said in the statement. “The recent emergence of the Omicron variant (B.1.1.529) further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19.“ae0fcc31ae342fd3a1346ebb1f342fcb The change to the agency’s guidelines comes days after the World Health Organization (WHO) named Omicron a “Variant of Concern” and just one day after the global health agency declared that the variant poses a “very high” global risk due to the possibility that it spreads more easily and could be resistant to vaccines or natural immunity. While data is still sparse, initial research shows that a significant number of physical changes to the virus’s spike protein “are concerning for their potential impact on the trajectory of the pandemic,” the agency wrote in a report it tweeted on Nov. 29. “Early data from South Africa suggest increased transmissibility of the Omicron variant, and scientists in the United States and around the world are urgently examining vaccine effectiveness related to this variant,” Walensky said in the statement. “I strongly encourage the 47 million adults who are not yet vaccinated to get vaccinated as soon as possible and to vaccinate the children and teens in their families as well because strong immunity will likely prevent serious illness.” RELATED: Moderna Just Made This Major Announcement About Its Booster. Even though no cases of Omicron have been reported yet in the U.S., Walensky urged the public to help stay ahead of the potential threat by using another familiar tactic. “I also want to encourage people to get a COVID-19 test if they are sick. Increased testing will help us identify Omicron quickly,” she emphasized. While news of the latest variant has caused concern among officials, vaccine makers appeared relatively optimistic in the face of Omicron. “I don’t think that the result will be the vaccines don’t protect,” Albert Bourla, CEO of vaccine manufacturer Pfizer told CNBC’s Squawk Box in a Nov. 29 interview. “I think the result could be, which we don’t know yet, the vaccines protect less.” RELATED: For more up-to-date information, sign up for our daily newsletter. In an address on Nov. 29, President Joe Biden echoed the CDC’s recommendations about getting the supplemental shot. “If you’re 18 years or over and got fully vaccinated before June the 1st, go get the booster shot today. They’re free, and they’re available at 80,000 locations coast to coast,” he urged. “A fully vaccinated boosted person is the most protected against COVID.” RELATED: These Are the Symptoms of the Omicron Variant, South African Doctor Says.