Kelly Marcilliat realized that something was terribly wrong with her thinking while driving last summer.
He stopped at a four-way stop – a situation Marcilliat, 55, from Denver, had been to thousands of times before. This time, however, he couldn’t figure out when it would be his turn to go.
“I sat looking at the intersection,” said Marcilliat, “thinking, ‘What the hell do I do?'”
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Cognitive problems arose months after he first fell ill with Covid-19, leaving him blind.
“When I was at the height of the disease because of the virus, initially, I didn’t feel dizzy. I just felt exhausted, ”he said.
Marcilliat is not alone: new research suggests that long-term symptoms of Covid-19 may appear in a different pattern over weeks and months.
Natalie Lambert, associate professor and researcher at Indiana University School of Medicine, interviewed thousands of Covid-19 long-hauler patients, finding that specific symptoms tend to appear at regular intervals – usually a week or 10 days – resulting in what it calls “symptom waves.”
Further research is needed to confirm the results, which have not been published in a medical journal or posted on a prepress server. But the first findings, which were shared with NBC News, could give doctors insights on how to treat long-haulers more effectively and perhaps even prevent debilitating symptoms.
Dr. Richard Walker, president of emergency medicine at the University of Tennessee Health Sciences Center in Memphis, said Lambert’s work was “very important research”.
“Whenever we can predict the course of the disease, it gives us the ability to mitigate the problems,” said Walker, who was not involved in the research.
Lambert researched 5,163 long-haulers. Patients were contacted online through the Survivor Corps website, a website dedicated to long distance. Seventy-seven percent of respondents tested positive for Covid-19 or were diagnosed by doctors based on their symptoms and exposure.
In the survey, Lambert asked patients what symptoms they had and approximately how long after the onset of the disease.
Overall, patients reported more than 100 symptoms. Not everyone is necessarily connected to Covid-19 – it will take time for researchers to resolve this.
But long-haulers tend to take notes carefully. “They usually monitor their symptoms week by week so that they can report to the doctor to try to get help,” said Lambert.
When Lambert specifically looked at the onset of symptoms, distinct patterns emerged.
“The first wave is clearly the most flu-like symptoms,” like fatigue, headache, fever and chills, she said. “So it looks like diarrhea, nausea and vomiting are usually five days later.”
The new waves do not mean that the previous symptoms disappear; these symptoms may persist or may disappear and reappear later.
Ten days after getting sick, another wave breaks. This time, the new symptoms tend to be more neurological, including confusion, dizziness and difficulty concentrating. Patients can also develop joint pain and low back pain. Some report a pressure on the brain so intense that it looks like their heads are going to explode.
Fifteen days after getting sick, another wave of new symptoms: high or low blood pressure, heart palpitations, tendency to faint.
A week later – about 21 days in hospital – patients begin to experience problems such as mouth sores, muscle spasms, eye infections and a skin condition that is known as “covered toes”.
Covid-19’s symptoms are variable, but overall, the first waves of symptoms – flu-like illness, gastrointestinal problems and neurological symptoms – tend to reflect what a typical non-long-distance patient would experience, said Dr. Rebecca Keith , associate professor of pulmonary medicine and intensive care at National Jewish Health in Denver. Keith is co-director of the facility’s post-Covid-19 clinic.
That is, there is no way to know from the beginning if a patient can become a long-distance farmer. In fact, there is still no standard criterion for defining or diagnosing long-haulers. Symptoms can come and go or can last for months.
“Once they start having symptoms after, like, six to eight weeks, people start to get really worried,” said Keith, who was not involved in Lambert’s research.
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Dr. Michele Longo, an assistant professor of neurology at Tulane University in New Orleans who works with long-haulers, said the neurological symptoms listed in Lambert’s research are, in fact, “most commonly reported by patients” in her clinic.
“Why there seems to be a predilection for neurological symptoms in the post-acute sequelae of Covid’s infection remains unclear,” said Longo, who was not involved in the research. (“Sequelae” is a Latin word that refers to conditions that occur after an illness.)
Keith agreed. “If we can define the paths that are contributing to this from a scientific point of view,” she said, “we can think about how to talk about therapies and hope.”
Patients are also desperate for answers.
“It is extremely disturbing not to be able to tell yourself why something is going on with you,” said Marcilliat. “It gives you a feeling of total lack of control, as if you were a leaf in the wind.”
“Nobody wants to be like that,” he said.
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