By Ethan Covey
More than half of people who are infected by the SARS-CoV-2 omicron variant may be unaware of their recent infection, according to a study conducted by researchers at Cedars-Sinai Health System.
The study’s findings reveal low levels of awareness regarding infection status may result in rapid spread of the virus, leading to surges in cases (JAMA Netw Open 2022;5[8]:e2227241).
“Awareness will be key for allowing us to move beyond this pandemic,” said Susan Cheng, MD, MPH, the director of the Institute for Research on Healthy Aging in the Department of Cardiology of the Smidt Heart Institute at Cedars-Sinai, in Los Angeles.
The study focused on adult employees and patients of an academic medical center who were enrolled in a longitudinal COVID-19 serological study. Participants received two or more anti-nucleocapsid immunoglobulin G antibody measurements, conducted at least one month apart. The first antibody measurement took place after the end of a regional surge of the delta variant, and the second test was conducted following the start of a surge caused by the omicron variant.
Of 201 participants who had serological evidence of recent omicron infection, 56% reported no awareness of their infection status. The vast majority of those who were unaware of having been infected with COVID-19 experienced no symptoms. Only 10% reported having symptoms that they attributed to either the common cold or other non–COVID-19 illness.
Among the study’s participants, employees of Cedars-Sinai were more likely to be aware of omicron infection than nonemployees, a factor that may be explained by hospital-related daily health screening measures.
“Our study findings add to evidence that undiagnosed infections can increase transmission of the virus,” said Sandy Y. Joung, MHDS, a clinical investigator at Cedars-Sinai and first author of the study. “A low level of infection awareness has likely contributed to the fast spread of omicron.”
“We hope people will read these findings and think, ‘I was just at a gathering where someone tested positive,’ or ‘I just started to feel a little under the weather. Maybe I should get a quick test.’ The better we understand our own risks, the better we will be at protecting the health of the public as well as ourselves,” Dr. Cheng added.
Dr. Cheng reported a financial relationship with Zogenix outside the submitted work.