As infections with the Omicron variant of SARS-CoV-2 spread rapidly across the United States and the world, questions have come up about whether the new variant will cause cases of post-acute sequelae of SARS-CoV-2 (PASC).
While it may feel as though we’ve been facing COVID and its lasting effects for a very long time, experts say that it’s still too early to say whether the new variant will lead to more cases of the syndrome dubbed “long COVID.”
PASC is also called chronic COVID, long-haul COVID, or long COVID. It refers to cases where people who were infected with COVID went on to have lasting symptoms, some of which have disrupted their lives significantly. The condition has emerged over the course of the pandemic but was only recently given a clinical name.
Long COVID is happening to people all along the spectrum of COVID illness—from those who were hospitalized to people who never even knew they had been infected.
According to the Centers for Disease Control and Prevention, the symptoms of post-COVID can include:
Linda N. Geng, MD, PhD, a clinical assistant professor of medicine at Stanford School of Medicine with a clinical focus on long COVID, told Verywell that the percentage of people who have symptoms that last after they get COVID ranges from 10% “up to even 70% to 80%.”
According to Geng, it’s too early to tell if the Omicron variant will cause long COVID because it takes time for the symptoms to emerge after the initial infection.
Geng adds that “the definition of long COVID or post COVID condition is still evolving.” Some health authorities have said that long COVID occurs when a person has symptoms that last for more than 4 weeks beyond the initial infection. Others define it as symptoms that last longer than 3 months.
The Omicron variant has only been circulating since late November and early December. That means that any long COVID cases that might be linked to it haven’t had time to pop up.
Gregory Poland, MD, a professor of medicine and infectious diseases at the Mayo Clinic, the founder and director of Mayo Clinic’s Vaccine Research Group, editor-in-chief of the journal Vaccine, and a spokesperson for the Infectious Disease Society of America, told Verywell that in general, that time frame is about 30 days. That means that “in terms of what we would call long haul, by definition, we’re not really there yet.”
Even before COVID, Poland said that researchers knew that viral infections could cause lasting symptoms or lead to complications that did not seem to be related to the original infection.
Now, long COVID “has forced us as clinicians to understand that viruses and viral infections can have seemingly disconnected symptomatology that can be chronic in nature. The tendency of the medical profession is to ‘pooh-pooh’ that.”
Geng agreed, adding that they think it’s “safe to say it is a big public health problem and it will continue to be as we continue to have additional COVID cases and outbreaks.”
Geng said that the widely different rates in the reported incidence of long COVID are at least partly the result of the various definitions of the syndrome. For example, if long COVID is defined as when symptoms last at least four weeks after infection, there would be more cases than if the definition stated that a person must be debilitated by symptoms that have lasted more than three months.
That said, there are steps being taken to prevent long COVID cases from falling through the cracks.
The World Health Organization (WHO) added a code for post-acute sequelae of SARS-CoV-2 to the International Classification of Diseases (ICD) in October. ICD codes are used to document diagnoses of diseases and conditions. The system should ensure that healthcare professionals are using the same methods to diagnose long COVID. It also will assist in the collection of information on cases.
The National Institutes of Health has also launched a research initiative of long COVID called RECOVER. According to Geng, the study will recruit many patients and ask epidemiological questions in more detail, with the ultimate goal to “understand, prevent, and treat post-acute sequelae of SARS-CoV2.”
Earlier versions of the COVID virus have been associated with lasting symptoms that have become known as long COVID. We’re still learning about this syndrome, and experts say that it’s too early to tell if the new Omicron variant will lead to more long COVID cases.
The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.