The most recent covid-19 outbreak, driven by a fluctuating mix of rapidly developing omicron subvariants, looks to be decreasing, with cases and hospitalizations beginning to decline. Long covid, an ill-defined catchall phrase for a combination of symptoms that can include excruciating exhaustion, difficulty breathing, chest discomfort, and cognitive fog, will continue like previous covid waves.

Although omicron infections are generally milder than those produced by last summer's delta variety, omicron has also been shown to cause long-term symptoms and organ damage. However, whether omicron causes long covid symptoms as frequently — and as severely — as prior variations is still being researched.

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Director of the University of Minnesota's Center for Infectious Disease Research and Policy, the considerably increased proportion of omicron infections compared to earlier variations indicates the need to prepare for a significant increase in people with long covid, according to Michael Osterholm.

As omicron has swept the country, the United States has registered nearly 38 million covid infections this year. According to the Johns Hopkins University Coronavirus Research Center, this represents almost 40% of all infections reported since the epidemic began.

What is long covid?

Long covid “is a parallel pandemic that most people aren’t even thinking about,” said Akiko Iwasaki, a professor of immunobiology at Yale University. “I suspect there will be millions of people who acquire long covid after omicron infection.”

Scientists have just recently begun to compare variants head to head, with mixed findings. While one recent study in The Lancet indicated that omicron is less likely to develop long covid, another found that both omicron and delta infections resulted in the same rate of neurological disorders.

Based on population disparities, estimates of the number of patients affected by extended covid range from 4% to 5% in triple-vaccinated individuals to up to 50% in the unvaccinated.

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One reason for the large range is that extended covid has been defined in widely varying ways in different studies, ranging from self-reported fogginess for a few months after infection to a severely impaired inability to control pulse and blood pressure that can last years.

Even if those forecasts are conservative, the sheer number of omicron infections this year would significantly increase long-covid caseloads. “That’s exactly what we did find in the UK,” said Claire Steves, a professor of aging and health at King’s College in London and author of The Lancet study, which found that patients have been 24% to 50% less likely to develop long covid during the omicron wave than during the delta wave.

“Even though the risk of long covid is lower because so many people have caught omicron, the absolute numbers with long covid went up,” Steves said.

Reinfections

A new study that examined a Veterans Health Administration patient database discovered that reinfections significantly raised the chance of serious health problems, even in persons with mild symptoms.

The research of over 5.4 million VA patients, including over 560,000 women, discovered that persons who were reinfected with covid were twice as likely to die or suffer a heart attack as people who were only infected once. They were also considerably more likely to have health difficulties of any kind six months later, including issues with their lungs, kidneys, and digestive tract.

“We’re not saying a second infection is going to feel worse; we’re saying it adds to your risk,” said Dr. Ziyad Al-Aly, chief of research and education service at the Veterans Affairs St. Louis Health Care System.

Are all studies accurate? 

Researchers revealed that the study, published online, should be interpreted with caution. Some noted that VA patients have unique characteristics and tend to be older men with high rates of chronic conditions that increase the risks of long covid. There were warnings regarding the study's findings that can't be extrapolated to the general population, which is younger and healthier. 

“We need to validate these findings with other studies,” said Dr. Harlan Krumholz, director of the Yale New Haven Hospital Center for Outcomes Research and Evaluation. Still, he added, the VA study has some “disturbing implications".

As fears mounted over the newly identified coronavirus variant #Omicron, here's a list of some of history’s most deadly pandemics 👇.#COVID19 #CovidVariant pic.twitter.com/wn2IqRG4N1

— Al Mayadeen English (@MayadeenEnglish) November 29, 2021

With an estimated 82% of Americans infected at least once with the coronavirus as of mid-July, the majority of new cases are now reinfections, according to Justin Lessler, an epidemiology professor at the University of North Carolina Gillings School of Global Public Health.

People's risk of reinfection is, of course, dependent not only on their immune system, but also on the precautions they take, such as masking, getting booster shots, and avoiding crowds.