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You haven’t been spreading the omicron variant without knowing it with no information

Omicron rates show that almost 1 out of 2 infected people didn’t know they had omicron.

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Even though omicron subvariant BA.5 has emerged as the COVID-19 variant that is now most infectious and immune-evasive, researchers have long recognized that many COVID-19 cases, regardless of variant, are absolutely asymptomatic. But it was difficult to say with any degree of accuracy how frequently the average person contracted COVID without realizing it.

The extent to which people may unknowingly be transmitting the COVID-19 omicron strain is been revealed by a new study. It was long believed that because omicron infections are typically asymptomatic, those who have them would unintentionally spread the virus because they were unaware of their infection.

More than half of those who got the omicron strain of COVID-19 were asymptomatic, according to a recent study published in the medical journal JAMA Network Open. As a result, they were likely unaware that they had ever been infected.

Related The widespread use of at-home testing may render the upcoming COVID-19 wave “invisible.”

Blood samples provided by 2,479 individuals and healthcare professionals were examined by Cedars-Sinai Hospital researchers during the time just before and during the initial omicron spike. Based on the presence of SARS-CoV-2 antibodies in their blood, scientists discovered 210 people in that cohort who appeared to have recently acquired the omicron version of the disease. They were asked to give regular updates on their health state. It was soon discovered that only 44% of the affected volunteers knew they carried the SARS-CoV-2 virus.

A crucial figure makes it clear why 56% of infected people were unaware: Only 10% reported experiencing any negative symptoms, and they typically attributed those to a cold or other ailment.

To learn more about how unsuspecting omicron carriers have contributed to the escalating pandemic, Salon contacted Susan Cheng, MD, MPH, a corresponding author of the paper and the head of the Institute for Research on Healthy Aging at the Smidt Heart Institute at Cedars-Sinai.

In an email to Salon, Cheng responded, “It is tough to say,” pointing out that in order to “measure how quickly a virus is spreading and what proportion of the spread is across or between people who were unaware,” “it is hard to capture complete or comprehensive data on infection status across a given community or population at a given point in time, and then at multiple points over a period of time.” The data from our study and others, however, “indicate that undetected infections have likely played a key role in the propagation of virus throughout the epidemic,” Cheng noted.

In a statement regarding their study, Sandy Y. Joung, MHDS, a researcher at Cedars-Sinai and the study’s primary author, shared a similar viewpoint.

More than half of those who acquired the COVID-19 omicron strain were asymptomatic, making it likely that they were never infected.

The results of our study “add to evidence that undetected illnesses can boost virus spread,” said Joung. “The rapid spread of omicron has probably been facilitated by a low degree of infection awareness.”

The doctor called this a “good question” and said that based on other studies as well as their own, “it is very reasonable to do rapid antigen testing in situations after there has been a known or strongly suspected exposure to someone with COVID.” Cheng was asked if, based on their research, she believes people should try to get tested for omicron even if they are asymptomatic.

The authors of the study stated that they would need to investigate a more diversified group of patients than those who participated in this study who were recruited solely from a single occupational field in order to learn more about omicron infections (in this case, health care).

To enroll large and diverse groups of people in a study, Cheng said, “it does often require a large health organization or an organization of a large number of people through some kind of structured effort.” She added that this would need to involve “not just a single point of engagement but continuing repeated engagement to follow how they are doing with antibody measures and health status over time.”

The medical professionals at Cedars-Sinai are not the only ones to issue a warning that the public is at risk due to a quiet wave of omicron infections. Philadelphia’s health commissioner, Dr. Cheryl Bettigole, expressed worry about this earlier this week while announcing that Philadelphia would be the first sizable American city to reinstate an indoor mask requirement.

If we wait much longer, Bettigole said, “it will be too late for many of our citizens since every previous wave of infections has been followed by a wave of hospitalizations, and finally a wave of deaths.” This is our opportunity to prepare for the pandemic and put on our masks until we have more details on how serious this new variant is.