My name is Erin, and I don't have Long COVID.

I'm not sure how I would know if I did.

Twenty-five years ago, in junior high, I came down with mono as it circulated through my social circle. Mononucleosis—known as the “kissing disease” because it can be spread by saliva—is an infection caused by the herpes virus Epstein-Barr. It can also be passed on via coughs and sneezes, and sharing drinks and food.

Not surprisingly, it’s common among teens and young adults.

More than anything, mono exhausted me, and kept exhausting me—long after the infection was over. Getting out of bed felt like a herculean task. Every morning I found myself sick, in pain, and burdened by some invisible weight I couldn’t quite describe. But I looked fine. And after the acute phase of mono, no one really believed me.

My friends with mono bounced back within days or weeks. But me? Flash forward to high school—usually a star student and teacher’s pet, I was failing and enrolled in night school with other so-called troublemakers because I was exhausted and couldn’t pry myself out of bed before 10 a.m.

The accusations of laziness and resulting shame were real. But the symptoms, as nebulous as they were, were even more so. I felt like I was living in an alternate reality, suffering in some invisible hell no one else could see or understand. My symptoms and character were regularly called into question.

Eventually I received a diagnosis of Chronic Fatigue Syndrome, a disorder involving extreme fatigue for six months or more that can’t be explained otherwise, and which rest doesn’t help. Other symptoms may involve aches and pains, temper lymph nodes, digestive issues, chills and sweats, muscle weakness, shortness of breath, brain fog, and an irregular heartbeat.

Sounds a little like Long COVID, huh?

There was no treatment, I was told, and left to soldier on as if nothing was happening, for fear I’d be accused of being slovenly yet again. Mentally, I struggled with the weight of others’ judgements. I was raised by Midwestern Boomers—lethargy was a sin, and so, I sloughed on. But as my friends ran track, played in the marching band, and attended parties, I felt like I was merely getting by, barely taking care of the basics while trudging through some foggy swamp filled with molasses.

Over time I learned to will myself out of bed—even when I felt like my body was on fire—and to mask my symptoms so others wouldn’t pretend to empathize with something they couldn’t understand.

As it turns out, what I went through—and am still going through—is quite similar to what some Long COVID patients are experiencing, says Dr. Alexandra Brugler Yonts, an infectious disease specialist at Children’s National Hospital in Washington, D.C. who runs its pediatric Long COVID clinic.

Chronic Fatigue Syndrome “is really the best parallel we have for Long COVID, mostly because the biggest factor they share are fatigue—this sort of push and crash, post-exertional malaise,” she says, adding that patients are often “a little better one day, normal the next day, and completely wiped out the next day.”

‘An unexplained chronic disability’

As researchers race to discover exactly what Long COVID is, some point out that sequelae—or consequences of a disease or injury—are by no means unique to COVID. Other viruses—like SARS, West Nile virus, polio, and H1N1 flu—have also been known to wreak long-term havoc, resulting in CFS and/or other maladies, experts pointed out this week at a Harvard Medical School-led Massachusetts Consortium on Pathogen Readiness media availability.

Such post-acute infection syndromes, or PAISs, have “long been associated with an unexplained chronic disability” and may share a common cause, the authors of a recent paper published in Nature, “Unexplained post-acute infections syndromes,” posit.

All such conditions are “characterized by a set of core symptoms centering on exertion intolerance, disproportionate levels of fatigue, neurocognitive and sensory impairment, flu-like symptoms, unrefreshing sleep, myalgia/arthralgia, and a plethora of nonspecific symptoms that are often present but variably pronounced,” they write.

“There’s a baseline level of fatigue, and as things progress, some may have more energy some days and less others,” Yont says. Exertion may cause fatigue sometimes, but not others—immediately, or the next day. The exertion doesn’t have to be physical—it could also be mental or emotional.

To make matters worse, sleep often fails to cure the fatigue.

As is the case with Long COVID, treatments can’t be developed until a cause is discovered—and as of yet, the cause of CFS is unknown. It’s currently a diagnosis of exclusion—labs typically show up normal, and only hypotheses exist as to what causes the condition.

One of the lessons emerging from Long COVID is the need for treatment clinics for complex conditions like CFS and Long COVID that require multiple specialists, Yonts says. Just because a direct treatment doesn’t exist doesn’t mean symptoms can’t be managed or that patients can’t benefit from seeing doctors from a variety of disciplines.

The condition is “too intense and time-consuming for a general physician,” she says. “I think it traditionally probably hasn’t had a lot of good follow-up, but I think it would benefit from it. Hopefully that’s the world we’re headed for.”

Nearly a quarter century and counting

Just how long might Long COVID linger in patients?

It’s the million-dollar question right now.

“There are definitely people who got infected [with COVID] in the beginning and are still having symptoms,” Yonts says. “There are Chronic Fatigue Syndrome patients who have had the condition for decades.”

“I think some people, somehow, are able to recover,” she says. But the widely accepted minimum duration for Long COVID “is six months—and on average, a lot longer than that.”

For me, it’s almost a quarter century and counting. While life is easier than it was in the days immediately following my mono infection, the condition has yet to resolve.

I don’t figure it ever will.

I have good days and bad. Feeling well is the exception, not the rule. Many mornings I feel as if I’ve come down with the flu until I heave myself out of bed and get going for the day. Often I eventually feel better—a common phenomenon, Yonts says. But some afternoons I struggle to keep my eyes open.

My son needs me; caring for him is what gets me out of bed every day. Yep, I had a kid—one is plenty exhausting, so I’ve kept it at that. I graduated high school, got a full-ride college scholarship, fell in love, left the full-ride scholarship, bought a house, married, divorced, fell in love again, bought another house—all the usual things. I finished my bachelor’s degree online, and these days, I often find myself with more energy. I’m currently working on four master’s degrees. I was one of 20 reporters chosen globally for a prestigious medical reporting fellowship last year.

I’m tired, but I’m still a workaholic.

Sometimes I wonder what it’s like to feel normal, to go to sleep and wake up refreshed.

I don’t think I’ll ever know.

But I know happiness. I know love. I know the satisfaction of a hard day’s work. I’ve accomplished all the common adult milestones and then some—more than most in my small-town high school class have accomplished, from what I’ve heard.

I wish I had some life-altering advice to share with those who are acclimating to the world of Chronic Fatigue Syndrome after COVID, or perhaps merely trying to survive it.

I don’t.

All I know is that nearly 25 years in, I’m still living with it. I can share that—and a reminder that humans are resilient.

There is life with CFS, even if we may never know a life after it.

This story was originally featured on Fortune.com