In what has become a familiar refrain amidst various Covid-19 variant surges, UCSF Chair of Medicine Dr. Bob Wachter began Grand Rounds by noting that “I probably threatened two or three months ago that we would stop doing these or slow them down, but that clearly was not the right call.”
This Thursday’s panel focused on the “firehose of new data related to omicron,” with a presentation on what we know about the omicron variant followed by a discussion on “what we should be doing in response to this new and rapidly evolving threat,” Wachter said.
Dr. Carlos del Rio, professor of medicine at Emory University’s medical school, said 82 percent of current cases are in Europe, “where the pandemic is very, very active right now,” said del Rio. Omicron, the new SARS-CoV-2 variant, was first detected in Botswana on Nov. 11 and has since “moved rapidly around the world.” It is most prevalent in Europe, with the United Kingdom “leading the charge” with more than 10,000 omicron cases.
Examining the spread across Denmark, the UK and France, there is a very rapid increase in cases but not yet a huge spike in the number of deaths, del Rio said, though deaths are beginning to go up in some of the countries.
Hospitalizations are starting to go up in South Africa, but not in intensive care units. Del Rio also noted that many people are in the hospital for another ailment and test positive during their time there, as opposed to being admitted to the hospital for covid symptoms.
Omicron is likely two to three times more transmissible than delta, del Rio said. The time it takes for the number of covid cases to double is two and a half to three days, “which is just incredibly, incredibly fast for cases to go up.” Three cases now could lead to 600 cases in two and a half days, and could keep growing exponentially.
Though there is no evidence that omicron causes more severe disease yet, del Rio cautioned that sample sizes are small and many of the sick individuals are young, “so we have to see.” He’s waiting to see omicron go through a nursing home or long-term care facility before talking about how severe it is, especially given the lag in boosters among care facility residents.
The good news is that those who have been previously sick and then get immunized have good protection, and that boosters seem to help.
Data shared by White House chief medical advisor Dr. Anthony Fauci on Wednesday showed that protection from infection against mRNA vaccines dropped from 80 percent before omicron down to 33 percent, but that doses are still effective at preventing 70 percent of hospitalizations in omicron patients in South Africa, and a study from the U.K. Health Security Agency showed that boosters increase protection against symptomatic disease to 75 percent.
Unlike other variants, previous infection is no guarantee against reinfection with omicron, as indicated by South Africa, where the reinfection rate has gone up.
Though there is no data regarding antivirals’ ability to fight data, del Rio said they “should be effective.” He and the other panelists were extremely excited by the impact of a new oral antiviral, Paxlovid, on treating severe illness and death. Paxlovid is also much easier to administer than other treatments that require intravenous drips.
Del Rio’s final advice was that we need to get vaccinated, boosted, and mentally prepared to be more cautious. Omicron will lead to a surge in the winter, but delta is our problem right now, he said. Over 55,000 people have been hospitalized, and the numbers are going up. If we superimpose omicron on top of that, “we may really be in big trouble,” he said.
Wachter then opened up the discussion to include two other panelists, who shared their thoughts
“What is most striking for me is the rapidity of spread,” Dr. Rachel Bystritsky, UCSF assistant professor of clinical medicine. “We were always concerned that something like this would happen, but this is beyond anything that I would have thought in terms of the doubling time of the number of infections and just how quickly things can change.”
“It’s been a really remarkable three- to four-week period,” said Dr. Paul Sax, professor of medicine at Harvard Medical School, who contrasted the excitement of new treatment and prevention drugs for covid with the omicron variant. “There is some thought that this is the pathway to endemicity faster.”
Endemic disease means that, instead of eliminating the covid, it will become more manageable on a societal level, like the flu. Sax said covid hospitalizations are still “way above” peak flu season, but “we may be heading” towards endemic covid.
Bystritsky also noted that, even though there may be 30 percent lower hospitalization rates (per South African data), hospitals may still be overwhelmed with the sheer number of cases induced by the high transmissibility rate.
Additionally, individuals who have not previously been ill or vaccinated may be just as likely to get omicron as they were the original strain of covid, Sax said. These individuals make up a “substantial fraction” of the United State’s population.
Del Rio also showed concern for the 40 percent of individuals in the United States who are not vaccinated, especially if previous illness doesn’t protect against omicron reinfection. Delta changed “a lot of people’s minds” about getting vaccinated, Bystritsky said, and she expects omicron will do the same.
Everyone, especially individuals who received the Johnson & Johnson vaccine, should receive an mRNA booster sooner rather than later, given the current surge.
For the holidays, Bystritsky recommends small gatherings, and rapid tests right before visiting, in addition to vaccines and boosters for attendees. The other panelists concurred with her recommendation, though Bystritsky said she would also wear masks in addition to the other precautions, and the other panelists did not. For those who are flying, del Rio recommended testing 24 hours before flying and 48 hours afterwards.
“While the current situation continues to be serious, we are in a much better place now than we were a year ago,” del Rio said. His final recommendations were to get vaccinated, boosted, continue wearing masks, and to be resilient.
See our previous Grand Rounds coverage here.