Linda Timmer wanted to practice what she preached.
While working at a domestic violence nonprofit in Arizona during the height of the Covid-19 summer wave in 2020, Timmer wrote pandemic policies for her workplace, encouraging her colleagues to wear masks and, if they had been exposed to the coronavirus or had symptoms, get tested.
Timmer herself was not aware of being exposed or having any Covid-19 symptoms, such as cough or fever, but she started experiencing some unusual moments when she felt fatigued or forgetful, along with several episodes of confusion.
“They weren’t really putting that in the list of symptoms to go get tested for,” said Timmer, now 64.
That August, “the brain confusion was so unusual for me that I just thought, ‘I’m telling everyone to wear masks and follow these policies; I better go get tested, too,’ ” Timmer said. She decided to get tested for Covid-19 at a drive-up site.
“I never expected to be positive,” she said, adding that she was “devastated,” because she did not want to miss work.
Not only did she test positive, that was just the beginning of a long battle.
Emerging research suggests that a small portion of people who now live with long Covid may have showed no Covid-19 symptoms at all when they were initially infected – or their symptoms were mild or unusual, similar to what Timmer had.
‘This was my most terrifying time in my life’
Within about two weeks, Timmer had recovered from acute Covid-19 infection. But as she returned to work, she still felt unusual, with problems like overheating, confusion, loss of taste, sound hallucinations and breathlessness.
“I realized the more I tried to walk or return to normal, my symptoms worsened severely, and I would end up in bed with pain and fatigue for weeks,” Timmer said.
“This was my most terrifying time in my life,” she said.
Timmer retired early – before her illness, she had not made plans to retire – and moved to New Mexico in November 2020 to live with her sister while she sought treatment for her ongoing symptoms. In February 2021, she moved to Michigan to live with her son.
Some people with long Covid have said that they noticed their symptoms ease after they got vaccinated against Covid-19. Research also shows that vaccines not only reduce the risk of severe disease and hospitalization, they can lower the odds of long-term Covid-19 symptoms.
Timmer was originally diagnosed with Covid-19 before vaccines became available in the United States. Once they were authorized for her age group, she got vaccinated – and boosted. She felt good after the first vaccine dose, but her long Covid symptoms persisted.
Timmer still has “debilitating” symptoms from long Covid, and she is not alone.
One preprint paper, posted last year to the server MedRxiv, featured an analysis of more than 1,400 medical records in California for people who tested positive for Covid-19. It found that roughly 32% of those reporting long-haul symptoms more than 60 days following a Covid-19 diagnosis had no symptoms at the time of their initial Covid-19 test.
“I’ve seen similar stuff in clinic, as well. Patients coming in with either no symptoms or some very mild symptoms like sore throat, cough, maybe some sneezing, and a few weeks later, debilitating headaches, inability to get up in the morning or just unrelenting fatigue and weakness. And before we knew that long Covid was really a phenomenon, we didn’t know what to do,” said Dr. Ali Khan, who specializes in internal medicine at Oak Street Health in Chicago.
In some people, “we are seeing the coronavirus itself interact with almost every single part of the human body, which is just so atypical for most diseases, particularly most viruses. So we see that in some people – even in people whose initial infections were silent – it can work in the bloodstream to cause you to be more likely to get a blood clot,” he said. “For other people, that coronavirus is attacking the nerves, and it’s causing nerve pain; it’s causing headaches; it’s causing longstanding sciatica that many of my patients are dealing with.”
‘Even people who did not have COVID-19 symptoms … can have post-COVID conditions’
The US Centers for Disease Control and Prevention describes long Covid, or “post-Covid” conditions, as a wide range of new, returning or ongoing health problems four or more weeks after acute Covid-19 infection.
“Even people who did not have COVID-19 symptoms in the days or weeks after they were infected can have post-COVID conditions,” according to the CDC. “These conditions can present as different types and combinations of health problems for different lengths of time.”
The consensus in the medical field is that Covid-19 is an “acute illness” and long Covid is a “subacute chronic illness,” said Dr. Adupa Rao, a pulmonologist with the University of Southern California’s Keck Medicine who sees long Covid patients through Keck Medicine’s COVID Recovery Clinic.
“In the medical world, acute illnesses usually mean a week to two weeks of illness. Subacute means anywhere from two to four weeks and chronic means anything from four to six weeks on that is persistent,” Rao said. “So, the chronic long Covid symptoms are usually people that don’t return to their baseline or close to their baseline after the initial infection – and being able to diagnose long Covid is quite difficult.”
Estimates of long Covid’s incidence range from about 30% to more than half of people who have recovered from acute Covid-19 infection. Women and older adults appear to be more likely to have it than men and younger adults.
Even though the risk of long Covid-19 appears to increase with the severity of acute Covid-19 infection, almost a third of people who had mild symptoms when they were originally diagnosed may still have symptoms months later, according to some estimates.
“We do know that even a mild or relatively asymptomatic acute infection with Covid can eventually cause long Covid,” said Dr. Gerald Harmon, a family medicine specialist and president of the American Medical Association.
“Anywhere from 10% to 30% of patients can experience symptoms of Covid after apparently recovering, even if they weren’t sick in the first place,” he said. “And it’s a wide range of new, returning or ongoing health problems that we typically have put into three different categories.”
The first category, Harmon said, includes people who have direct cell damage that was caused by the coronavirus during the initial infection and takes a long time to recover from. Examples include acute kidney damage, acute lung damage, a big infection of pneumonia in the lung or a blood clot in the brain.
The second category describes people hospitalized with Covid-19 who may have long-term complications from being bed-bound for weeks, such as neurological damage, lung damage or muscle weakness.
Experts are “probably more concerned with” the third category, Harmon said. It includes anyone who recovered from an initial Covid-19 infection that wasn’t severe but then had symptoms.
“And they’re thinking, ‘My goodness, is this a recurrence of the Covid infection? Is it delayed? Is it a new something that’s masquerading as Covid? Or is it Covid masquerading as something more common, such as pneumonia?’ ” Harmon said.
One review paper analyzed 11 studies published between December 2019 and September 2021 on people with asymptomatic or mild forms of Covid-19. The analysis suggests that long Covid develops on average in about 30% to 60% of patients, with fatigue, shortness of breath, cough, or loss of taste and smell as the most common symptoms.
Many studies on long Covid tend to lump together people who initially had asymptomatic or mild infections, Dr. Linda Geng, co-director of Stanford Health Care’s Post-Acute COVID-19 Syndrome Clinic, wrote in an email.
For instance, one of that review paper’s findings was that presence of anosmia, or loss of smell, during an asymptomatic or mild course of the disease can be “predictive factors” for the development of long Covid. If there is anosmia, then someone is not completely asymptomatic, Geng wrote.
In other studies, “some of the patients who were labeled ‘asymptomatic’ may have had some symptoms that were not brought to medical attention or captured” in their electronic health records, Geng wrote.
“Some patients didn’t think they had COVID until getting tested and thought instead that it was just some allergies or something else. All that to say it can be hard to make clear conclusions from studies due to certain limitations and complexities. We need further study in this area,” she said. “Regardless, it is clear that you do NOT need to have severe acute COVID to develop Long COVID.”
‘She didn’t want to live in a wheelchair’
Los Angeles-based filmmaker Nick Guthe says his wife, screenwriter Heidi Ferrer, was among those who did not initially have a severe Covid-19 infection but still developed debilitating long Covid symptoms.
In April 2020, Ferrer showed signs of Covid toes – which involves discoloration and swelling – “and that concerned her because she had been reading about Covid, and she had some very mild GI symptoms that were a slightly upset stomach for a day or two. That made her think that she should get tested,” Guthe said. “So she didn’t have the serious pulmonary issues that some people have, where their breathing is really messed up.”
Guthe and Ferrer visited a drive-through Covid-19 testing site at the University of California, Los Angeles. They both had their cheeks swabbed and tested negative.
But within six weeks, Ferrer’s Covid toes had worsened, making it excruciating to walk. The woman who used to walk for 90 minutes a day could barely go 100 feet without stabbing nerve pain in her feet – similar to diabetic neuropathy.
On May 28, 2020, “I remember her birthday at my mom’s house very distinctly because she had to sit with her feet on a pillow and she couldn’t wear sneakers anymore. They were too painful. She had to basically wear them just to walk on pavement and then take them off whenever she got in the house, and she put her feet on pillows,” Guthe said. “It was her 49th birthday.”
As Ferrer’s symptoms progressed, Guthe said, she had severe gastrointestinal issues, exhaustion, a racing heartbeat from just getting out of bed, brain fog, changes in vision, intense tremors and internal vibrations, which led to weeks of insomnia.
“She had tremors in her upper torso and shoulders and upper extremities, but they weren’t in the legs yet, but that’s where she thought she was going to end up,” Guthe said. “And she didn’t want to live in a wheelchair.”
Even though Ferrer did not initially test positive for Covid-19, she had a cytokine panel done at a long Covid clinic in the San Francisco Bay area early last year to look for clues behind her symptoms, searching for inflammation and signs of long Covid.
When the results came back, Ferrer’s practitioner felt comfortable referring her to a long Covid clinic at Cedars-Sinai, Guthe said, but a mixup meant that referral letter arrived about 10 days later than intended.
It finally came on May 21, 2021 – a day before Ferrer took her life.
“I often wonder if it had arrived for her on the correct day – 10 days previous – would that have made a difference for her, because she would have felt some level of hope,” Guthe said. “But, I mean, hindsight is 20/20.”
Guthe hopes the medical community can learn from his wife’s story.
How to get help
In the ER, on the day Ferrer died, Guthe said the doctor asked, ” ‘How long has your wife been depressed?’ And I said, ‘She wasn’t depressed. She was in excruciating pain from long Covid.’ And he said, ‘What’s long Covid?’ I said, ‘You’re kidding, right?’ And he said, ‘No, I don’t know what it is.’ ”
Guthe told the doctor to “just Google it.”
“May 22nd will be the anniversary of my wife’s suicide, and in some ways, it’s been extremely frustrating to see how little changed this year,” Guthe said. “The only thing that has changed is the public’s awareness of long Covid.”
Pulling back the curtain on long Covid
Although physicians know more about Covid-19 now than they did two years ago in the early days of the pandemic, the medical community still doesn’t “have all the answers” when it comes to the disease – and especially long Covid, said the American Medical Association’s Harmon.
The association held a special meeting of its House of Delegates in June at which delegates adopted a policy to show support for the development of specific medical codes for doctors to use when diagnosing and treating “post-acute sequelae of Covid-19,” or long Covid.
In October, a diagnostic code was announced to specifically document post-acute sequelae of Covid-19 rather than active infection.
Currently, there is no lab test that can definitively distinguish long Covid symptoms from other medical problems. But specific medical codes for long Covid can help health care providers when diagnosing and treating someone with a history of Covid-19 who has long Covid symptoms – or a completely different medical concern.
“It may have zero to do with your recent Covid infection or remote Covid infection,” Harmon said. “So if you’re having some symptom that you’re not sure about, talk to your doctor. You might simply have a different infection. You could have a pneumonia infection; you could be having had a tick bite and have a tickborne illness. You could have strep throat. You could have the flu.”
After all, “many things can masquerade as Covid, and unfortunately, post-Covid can masquerade as many things,” he said. “Right now, there’s no diagnostic tests per se – say, ‘let’s do a strep throat test; let’s do a flu test to see if you’ve got long Covid or not.’ There is no one test, so it becomes what we would call a diagnosis of exclusion.”
In other words, “you need to exclude other potential conditions that can cause those symptoms before attributing it directly to COVID,” Stanford Health Care’s Geng wrote in her email.
It is still “very difficult” for doctors to confirm when people who initially had asymptomatic or mild Covid-19 develop long Covid symptoms, Dr. Zijian Chen, medical director for Mount Sinai’s Center for Post-COVID Care, wrote in an email.
“We definitely have patients who have mild to no symptoms during a patient’s acute infection who then go on to develop long covid,” Chen said.
“The best we do is to evaluate the patient, and look for occult causes that are not covid. If we do not find another cause, and the covid infection happens relative to when the symptoms begin, we can say that it is likely the infection led to the patient developing symptoms,” Chen wrote, adding that “we do comprehensive evaluation to make sure there is not another cause.”
‘No one should be left behind’
Even though there is now a diagnostic code in the United States to help identify post-Covid symptoms, long Covid remains a mystery in medicine.
While spending time with her son in Michigan, Timmer often thinks about long Covid and how it manifests in her body. Sometimes, the exhaustion becomes overwhelming, her body aches, short-term memory loss makes conversations difficult, gastrointestinal issues are unrelenting, and there has been a constant, disruptive ringing in her ears.
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There is still much to learn about Covid-19, and Timmer wants members of the medical community to know that they can and should listen to those with long Covid when seeking answers.
During her journey with Covid-19, she has “constantly” felt the need to defend her symptoms, and it’s “exhausting.”
“Long-haul asymptomatic people are unique in their awareness that these long haul symptoms are not normal and the fact medical procedures and tests do not reveal any issues for people,” Timmer said. “I hope the medical research continues and every long-haul survivor has the help needed to move forward, such as more clinics specializing in long-haul, medical insurance and transportation. No one should be left behind in the research of all things related to Covid-19.”