A new study of nearly 70,000 Covid patients in California demonstrates that Omicron causes less severe disease than other coronavirus variants.
The new research, posted online Tuesday, aligns with similar findings from South Africa, Britain and Denmark, as well as a host of experiments on animals. "It's truly a viral factor that accounts for reduced severity," said Joseph Lewnard, an epidemiologist at the University of California, Berkeley, and an author of the study, which has not yet been published in a scientific journal.
Compared with Delta, Omicron infections were half as likely to send people to the hospital. Out of more than 52,000 Omicron patients identified from electronic medical records of Kaiser Permanente of Southern California, a large health system, Dr. Lewnard and his colleagues found that not a single patient went on a ventilator during that time.

A UC Berkeley study has found several surprising insights on how COVID-19 is affecting India, a country of 1.3 billion people. The median hospital stay before death from the virus was five days, compared with two weeks in the United States, possibly because of limited access to health care. The trend in increasing deaths with age seemed to drop off after age 65, perhaps because Indians who live past that age tend to be relatively wealthy and have access to good health care. The study also found that children of all ages can become infected and spread the virus to others. An overwhelming majority of coronavirus cases globally have occurred in resource-poor countries, noted Joseph Lewnard, an epidemiologist at the University of California, Berkeley, who led the study. But most of the data has come from high-income countries. "It still surprises me that it took until this point for a lot of data to come out of a low- or middle-income country about the epidemiology of Covid," he said.

COVID-19 patients treated at Kaiser facilities in California and Washington have been requiring longer hospital stays and are more likely to need intensive care than patients in China, according to a new analysis conducted by Berkeley researchers and Kaiser Permanente. The findings indicate that the burden the crisis has placed on U.S. hospitals may have been higher. "The hospital resources needed to meet the needs of severely ill patients are substantial," says assistant public health and epidemiology professor Joseph Lewnard, the paper's lead author. "We found that observations from China may not provide a sufficient basis for anticipating the U.S. health care demand." For more on this, see our press release at Berkeley News. Stories on this topic have appeared in dozens of sources, including CBS Bay Area Online, News Medical, California EPeak.