Shortness of breath, loss of taste and smell, and other lingering Covid symptoms tend to ease over time and may be gone within a year, according to new research.

The findings may offer a bit of reassurance to people whose frustration increases as they continue to feel sick long after their initial Covid infection.

“For the vast majority of patients,” said study author Maytal Bivas-Benita, “this will get better.”

The new research, a collaboration between KI Research Institute and Maccabi Healthcare Services in Israel, was published Wednesday in The BMJ, a medical journal.

Bivas-Benita and her colleagues analyzed medical records, looking for documentation of symptoms lasting more than a month, for nearly 2 million people who sought Covid tests from the beginning of the pandemic through October 2021.

The study did not include patients who developed long Covid from omicron or its subvariants, but doctors in the U.S. say they do see new patients with long Covid symptoms following an omicron infection.

Patients included in the new study generally had mild Covid illnesses. That is, they were concerned enough about their symptoms to make a doctor’s appointment, but not sick enough to be hospitalized.

Most common long Covid symptoms

Three years into the pandemic, it remains unclear exactly how many people have long Covid. Estimates have ranged from 5% to more than 30% of Covid cases, largely because there is no standard definition of the condition.

But there are similarities among many patients.

The most common symptoms reported two months after the initial Covid infection included:

• Loss of taste and smell.
• Trouble breathing.
• Difficulty with concentration and memory.
• Fatigue and weakness.

Subsequent strep throat infections were also often reported, the study found.

Other symptoms — such as chest pain, cough, muscle aches and hair loss — tended to fade away within a year. Women were more likely than men to talk to their doctors about Covid-related hair loss.

Loss of taste and smell persists

No matter when they occur, all of these symptoms understandably leave patients “confused and worried,” Bivas-Benita said. Her research found, however, that “only a few symptoms persisted for a year after infection.”

One of those was the loss of smell and taste, she said, that seemed to “stick” for at least 12 months.

The findings are consistent with what long Covid experts in the U.S. have found.

“A lot of these patients will naturally get better over time,” said Dr. Ben Abramoff, director of the Post-Covid Assessment and Recovery Clinic at Penn Medicine. “One of the things we tell our patients is that sometimes the best medicine is time.”

Dr. Greg Vanichkachorn, an occupational medicine specialist who heads the Covid Activity Rehabilitation Program at the Mayo Clinic in Rochester, Minnesota, was not surprised by the findings.

Symptoms like muscle aches and shortness of breath, he said, do tend to get better over time, though they might not totally resolve.

“Improvement does not necessarily mean symptom resolution, and some folks are still suffering serious symptoms two years or more out from their infection,” Vanichkachorn said.

Because the Israeli study relied on medical records rather than hearing directly from patients, Abramoff and Vanichkachorn cautioned that the findings could underestimate long Covid symptoms. Not all symptoms are documented in doctors’ notes following a patient exam.

“We don’t really get a sense of how severe some of these symptoms are,” Abramoff said.

While the study found that many long Covid symptoms abate within a year, it remains clear that some patients continue to suffer long afterward.

“There is a group of patients and individuals who do not get better and continue to have symptoms over longer periods of time,” Abramoff said. “If you ask any long Covid clinic in the country, most of the patients we see — three, four or five months out — are continuing to have severe symptoms. Many of those patients are not better at one year.”