RELATED: These 9 States Are Seeing the Worst COVID Surges Right Now. According to data released by the CDC, the Omicron variant still only makes up a fraction of COVID-19 cases nationally in the U.S. as Delta remains dominant. However, during the week that ended on Dec. 11, the variant’s share jumped to 2.9 percent of cases from 0.4 percent the previous week. And in region 2—an area comprised of New York and New Jersey, as well as Puerto Rico and the U.S. Virgin Islands—Omicron cases had already jumped to 13.1 percent overall, making its spread four times faster there than anywhere else.ae0fcc31ae342fd3a1346ebb1f342fcb The news of the fast initial spread of Omicron in New York and New Jersey comes as officials from the CDC warn that the variant could create a surge of cases across the U.S. in the coming weeks. In a call on Dec. 14, officials warned that a spike could develop as early as next month, likely coinciding with a rise in Delta infections and cases of the flu. “The early signals say there are going to be waves coming,” Scott Becker, chief executive officer of the Association of Public Health Laboratories, said during a call with reporters on Dec. 14, according to The New York Times. “We are already expecting an uptick, just because we have seen a lot of respiratory viruses already this fall, including R.S.V. [respiratory syncytial virus, or the common cold], which was extensive.” For more pandemic news sent right to your inbox, sign up for our daily newsletter. Health officials have expressed concerns that the latest version of the virus is more transmissible than previous variants, with some recent spikes seeming to confirm their fears. “Omicron is spreading at a rate we have not seen with any previous variant,” Tedros Adhanom Ghebreyesus, MD, the director-general of the World Health Organization, said in a news briefing on Dec. 14. A recently released study conducted by Discovery Health—the largest private health insurer in South Africa—also appeared to provide evidence about initial concerns over how the variant interacts with vaccines. Data collected from more than 211,000 people who tested positive for the virus showed that the 90 percent effectiveness provided by two shots of the Pfizer vaccine against symptomatic infection drops to 33 percent against Omicron, USA Today reported. Protection against severe COVID was still found to be around 70 percent in patients who are fully vaccinated, however, even though this number began to diminish in patients above age 60 and even more so above age 70. The study’s authors pointed out that questions remain about the effectiveness of boosters against Omicron and warned that the highly transmissible variant could still lead to surges that may overwhelm healthcare systems. “The Omicron-driven fourth [wave] has a significantly steeper trajectory of new infections relative to prior waves,” Ryan Noach, MD, CEO of Discovery Health, said in a statement. “National data show an exponential increase in both new infections and test positivity rates during the first three weeks of this wave, indicating a highly transmissible variant with rapid community spread of infection.” Fortunately, other officials have said that while the variant is spreading quickly, there may be some good news in recent discoveries about Omicron. During the call with members of the press, CDC Director Rochelle Walensky, MD, said that the latest version of the virus “is demonstrating some decreased severity, shorter lengths of stay, fewer people on oxygen, fewer people in the ICU,” adding that “we have the tools now” to fight the variant. However, Walensky also tempered her optimistic outlook. “You still have a lot of people who are getting sick,” she said, warning that those who are especially vulnerable to COVID could still see a severe outcome from the virus. She also emphasized that the highly transmissible nature of the variant made getting as many people vaccinated as possible even more important. RELATED: These Are the Symptoms of the Omicron Variant, South African Doctor Says.