Becker's Clinical Quality & Infection Control

11 INFECTION CONTROL Next variant could be more transmissible than omicron, WHO says By Erica Carbajal T he World Health Organization's COVID-19 technical lead dismissed the- ories that the next potential COVID-19 variant will be milder than earlier strains and explained why it will likely be more contagious than omicron. "Omicron will not be the last variant that you will hear us talking about," Maria Van Kerkhove, PhD, the WHO's technical lead on COVID-19, said Jan. 25. "e next variant of concern will be more fit, and what we mean by that is it will be more transmissible, because it will have to overtake what is currently circulating." What's more important, however, is whether future variants will cause more or less disease severity, Dr. Van Kerkhove said, adding that global health officials do expect there to be more immune escape with future variants, which means vaccines may be less effective against them. She emphasized the importance of inter- ventions, such as ramping up global vaccination coverage, to slow the current spread and prevent the emergence of new variants. e WHO official warned against assuming that the virus will become milder as it continues to mutate. "ere is no guarantee of that," Dr. Van Kerk- hove said. "We hope that is the case, but there is no guarantee of that and we can't bank on it." e bottom line is that "variants are a wild card," Dr. Van Kerkhove said, adding that officials are still learning about the virus and don't have a complete picture into its future trajectory. "What we do know is vaccines work. Vaccines prevent people from needing hospitalizations and prevent people from dying," she said. More than 21 million new COVID-19 cases were reported globally for the week ending Jan. 23 — a global record for new weekly cases, the WHO said in its epidemiological update. The WHO's Director-General, Tedros Adhanom Ghebreyesus, PhD, said global conditions are ripe for new variants to emerge during a Jan. 24 briefing. "It is dangerous to assume that omicron will be the last variant, or that we are in the end- game," he said. n Prior infection 56% effective at preventing omicron, researchers estimate By Mackenzie Bean A previous COVID-19 infection may offer less protection against fu- ture symptomatic infections from omicron compared to other vari- ants, according to research published Feb. 9 in The New England Journal of Medicine. Researchers from Weill Cornell Medicine-Qatar in Doha conducted the study. To estimate protection levels from past infection, they analyzed data on COVID-19 testing, vaccination, infections, hospitalizations, deaths and patient demographics collected in national databases since the start of the pandemic. A previous infection was 56 percent effective at preventing reinfection from omicron, compared to 92 percent for delta, 90.2 percent for alpha and 85.7 percent for beta, researchers estimated. "Such protection against reinfection with the omicron variant was lower (approximately 60 percent) but still considerable," they said. No reinfections caused critical or fatal COVID-19 cases. A previous infec- tion was 87.8 percent effective at preventing severe, critical or fatal cases against omicron, 69.4 percent against alpha, 88 percent against beta and 100 percent against delta. "The protection of previous infection against hospitalization or death caused by reinfection appeared to be robust, regardless of variant," re- searchers said. n What happened to contact tracing? By Mackenzie Bean O nce touted as a key strategy to prevent the coronavirus's spread, contact tracing has since taken a backseat to vaccinations and mask-wearing amid the pandemic. As of Jan. 28, more than a dozen states had scaled back contact tracing efforts, according to the National Academy for State Health Policy. Some states cited skyrocketing case numbers amid the omicron surge as the reason for ending or scaling back contact tracing. Virginia limited contact tracing efforts Jan. 25. The state no longer investi- gates every COVID-19 case and instead focuses contact tracing efforts on cases and outbreaks in high-risk settings, such as long-term care facilities. Massachusetts closed its contact tracing program in December 2021 to focus on COVID-19 testing and vaccine outreach, citing the omicron surge as the main reason. Nebraska also amended its contact tracing program last December, shifting focus to large clusters of infections versus individ- ual cases. Nationwide, omicron cases appeared to peak Jan. 14, with a seven-day case average of 806,795. During the delta surge, the seven-day case average hit 164,374 Sept. 2, according to data tracked by The New York Times. n

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