Three new studies on Wednesday suggested that the omicron variant is less severe than previous Covid variants, The New York Times reports.
A South African study found that omicron has a 70% lower risk of hospitalization than previous variants.
The study suggests that people who have already had Covid may be more likely to reinfection due to omicron but also tend to have a strong immune response after people are infected.
South Africa estimates that about 70% of its population already had Covid, which may contribute to the lower severity. About 30% of the country has been vaccinated.
Among people who were hospitalized for omicron, patients had a similar risk of severe illness whether they had previous immunity or not.
“Given that this is everywhere and given that it’s going to be so transmissible, anything that would lower severity is going to be better,” Natalie Dean, a biostatistician at Emory University, told the Times.
Fewer hospitalizations than Delta:
A Scottish study found that the risk of hospitalization from omicron is about two-thirds lower compared to the Delta variant.
But Mark Woolhouse, a co-author of the study and an infection disease expert at the University of Edinburgh, cautioned that despite the lower hospitalization risk, hospitals may still fill up quickly due to the rapid spread of infections.
“So this is a qualified good-news story,” said Jim McMenamin, another co-author and the national Covid-19 incident director at Public Health Scotland.
UK study less optimistic:
Another study from researchers at Imperial College London also found a reduced risk of hospitalization but a smaller one than the other studies.
The study estimates that individuals infected with omicron at 15 to 20% less likely to go to the hospital than those with Delta.
The study also found that individuals with omicron are 40 to 45% less likely to be hospitalized overnight.
The study suggests that acquired immunity helps reduce the severity of infections.
“If you are unvaccinated and you have never been infected, it is a little less severe than Delta,” Dr. Bill Hanage, an epidemiologist at Harvard, told the Times. “But that’s a bit like saying you’re being hit over the head with one hammer instead of two hammers. And the hammers are more likely to hit you now.”