There are more than 200 symptoms associated with long Covid spanning 10 organ systems —including memory loss, hallucinations, tremors and fatigue—according to a new study published Thursday, providing one of the most comprehensive insights yet into the lingering and debilitating illness that can affect patients for months or years after infection.

KEY FACTS
Covid long haulers reported a total of 203 different symptoms in the seven months between Dec. 2019 and May 2020, ranging from rashes, peeling skin and digestive issues to muscle spasms, hearing loss and tinnitus, according to research published in the Lancet’s E Clinical Medicine journal.

The study, based on surveys from nearly 4,000 people from 56 countries, identified fatigue, brain fog and post-exertional malaise (where symptoms worsen after physical or mental effort) as the most common symptoms.

On average, patients suffered from 56 different symptoms and those still suffering after six months—nearly two-thirds of participants taking the survey—were still experiencing an average of 14 symptoms.

Almost half (45%) of the study’s participants reported needing a reduced work schedule on account of their illness and around one-fifth (22%) were unable to work at all.

Dr. Athena Akrami, a neuroscientist at University College London and senior author of the study, said it highlights “a clear need to widen medical guidelines” to assess a wider range of symptoms than respiratory and cardiovascular issues for long Covid.”

SURPRISING FACT
The researchers noted that patients reported experiencing symptoms that are “not commonly mentioned in public discussion of long Covid,” like seizures, suicidality, facial paralysis, new allergies and changes in sensitivities to medication.

KEY BACKGROUND
The findings reinforce the understanding that Covid-19 is far more than a respiratory illness and has an effect on the entire body. It also highlights that some symptoms may only emerge after months or weeks of the initial infection. Severity of the initial infection does not appear to be strongly linked to the chances of getting long Covid, making children and young people—along with the unvaccinated—especially vulnerable. Given that the majority of early research only covered hospitalized patients and the continued lack of consistent diagnostic criteria, it’s not yet known how common long Covid might be. Studies suggest around 10% to 30% of Covid-19 patients may go on to become these “long haulers,” though this figure is likely to change as more research is conducted.

WHAT WE DON’T KNOW
There’s also no sense yet of the duration of long Covid. The researchers estimated more than 90% of the cohort studied to still experience symptoms after six months. Other post-infection syndromes can vary from weeks to decades in duration, some only manifesting long after the initial infection is cleared. Dr. David Strain, a senior clinical lecturer at the University of Exeter, told Forbes the nearest illness to long Covid is probably chronic fatigue syndrome (also known as ME), which can last decades.

BIG NUMBER
33.9 million. That’s how many people in the U.S. have had Covid-19, according to data from Johns Hopkins University. Using a conservative estimate of 10% for how many people go on to develop long Covid and subtracting how many have died from Covid-19, that’s 3.3 million Americans who could be living with persistent, debilitating symptoms.

WHAT TO WATCH FOR
Akrami says the prevalence and often hidden nature of long Covid justify a national network of dedicated clinics to identify and treat patients suffering from the condition. There are already at least 41 hospitals offering post-Covid clinics across the U.S., according to Becker’s Hospital Review.

FORBES