What we currently know about the prolonged risk of COVID-19

In a study published on August 6, lancetresearchers asked more than 76,000 adults to regularly complete a digital questionnaire asking about 23 symptoms commonly associated with long-term COVID.

Surveys were sent between March 2020 and August 2021. Distributed in the Netherlandsa variant of Delta appeared domestically at the end of this period.

Too few people were vaccinated for the researchers during this period to see if vaccination affected long-term risk of developing COVID.

Over 4,200 participants contracted COVID-19 during the study. This was indicated by a positive test or doctor’s diagnosis. These people were matched to a control group of over 8,400 similar but uninfected people.

By looking at the symptoms people experienced before and after infection, as well as those in people who had never been infected with the coronavirus, researchers were able to identify a core group of long-term symptoms of COVID.

These include chest pain, difficulty breathing, pain while breathing, muscle pain, loss of taste and/or smell, tingling in the hands and feet, lumps in the throat, alternating heat and cold, heavy arms and legs, and / Or general fatigue.

The mean severity of these symptoms plateaued 3 months after infection and did not decline during the study period.

Several other symptoms developed in people infected with COVID-19, but the severity of symptoms did not worsen 3-5 months after infection: headache, itchy eyes, dizziness, back. pain, nausea.

Based on the difference in the incidence of symptoms between COVID-19 patients and controls, the researchers estimate that 12.7% of the COVID-19 patients in the study had long-term symptoms due to coronavirus infection.

The study suggests that at the time of the study, 12.7% of the general population infected with SARS-CoV-2, or about 1 in 8 people, were at risk of experiencing long-term COVID. .

Because the authors examined pre- and post-onset symptoms of COVID-19 and included a control group, this study provides a stronger estimate of how common COVID is.

However, this study was conducted before the emergence of the highly infectious Omicron subspecies and before the widespread use of the COVID-19 vaccine, so the results may not apply to the current situation.

Research suggests that vaccination reduces long-term risk of developing COVID.

in one study Italian health workers infected with COVID-19 who received two or three doses of the vaccine had a lower long-term risk of COVID-19 than unvaccinated people, published in July 2022. rice field. This study was conducted between He March 2020 and He April 2022, so it included the period during which Delta and Omicron were in circulation.

other research A paper published in June 2022 suggests that the risk of developing long-term COVID is lower with Omicron than with Delta.

However, as the authors of this paper point out, the actual number of people who develop long-lasting COVID may still be significantly higher, even if the variant caused the spike in cases to lower the risk of omicron. there is.

Additionally, some people can have severe and long COVID even if they have Omicron.

“There’s no question that post-COVID cases are as severe as they were a year ago, so it’s not that cases are less severe in general,” said Dr. Aaron FriedbergClinical Assistant Professor of Internal Medicine, Ohio State Wexner Medical Center, Columbus.

The medical center’s post-COVID recovery program sees patients whose symptoms have lasted at least four weeks, and some have lasted three months to two years.

Previous coronavirus infections may also influence the risk of developing COVID over time. This, along with immunizations and other factors, willimmune wall”

Currently, “the population has a very high baseline level of protection,” Friedberg said. is very rare at the moment.”

Another limitation of the new study is the additional symptoms Since then, “brain fog”, worsening symptoms after physical or mental exercise (a.k.a. “post-exercise fatigue”), depression or anxiety have been added to the long list of COVID.

1 study A paper published in July 2022 found that more than half of hospitalized COVID-19 patients had some cognitive impairment one year after discharge.

Future studies should examine the prevalence of these other symptoms after coronavirus infection and the prevalence of long-term COVID in children and teens. People with potentially long-lasting symptoms.

There are no treatments specifically approved to treat long-lived COVID, but Friedberg said through research and clinical experience, doctors are “tremendous” in finding ways to address specific symptoms of long-lived COVID. said to have been successful.

This includes physical therapy and rehabilitation, treatments such as targeted breathing, and treatments to manage neurological symptoms such as chronic pain and numbness, and cognitive symptoms such as brain fog.

He recommends that long-term COVID patients seek out professionals to help manage their symptoms, ideally working as part of a multidisciplinary clinic.

Other long-term COVID treatments are in development, including those specific to aspects of the condition.

Axcella Therapeutics is a biotechnology company located in Cambridge, Massachusetts. release Preliminary results from a Phase 2a clinical trial for the treatment of long-term COVID-related fatigue were announced on August 2nd.

In this study, a group of 41 patients received the company’s special combination of six amino acids and derivatives twice daily for 28 days or an inactive placebo on the same schedule.

Those who took the amino acids showed improvements in self-reported mental and physical fatigue compared to those who took the placebo.The researchers found that the treatment was also well tolerated. did.

Additional clinical trials, including a larger Phase 3 trial, are needed to find out how this treatment might affect long-term patients with COVID before regulators approve the treatment. Is required.

Axcella’s trial focused on people who had had COVID symptoms for at least three months, in this case fatigue.

Doctor Margaret KozielAxcella’s Chief Medical Officer explained why this cutoff was chosen: In other words, there is little natural resolution of symptoms. ”

This is consistent with the plateauing of symptoms seen in the study. lancet at the same time.

But Koziel said some patients in the trial had symptoms lasting much longer, including those who were sick when the pandemic first hit in the UK and are still feeling fatigued.

As for prevalence, Koziel said, based on recent estimates, more than 26 million Americans are likely infected with COVID over the long term. American Society of Physical Therapy and Rehabilitation.

Not all of those people will have severe symptoms, but Koziel believes they’ve had enough of the severe fatigue from prolonged COVID to have a negative impact on society.

“Some people can’t go back to work, and even if they do, they’re less productive because they have to reschedule so they don’t feel sick,” she said.