There's growing evidence that the coronavirus can affect different people in different ways. The length of the infection, severity of the symptoms and the recovery process all vary from patient to patient, and there is still much to learn about the disease. One woman in Canada says she's had the coronavirus for 50 days, and even though she's started feeling better, she still keeps testing positive.
Tracy Schofield, who is a nurse, told Canada's CTV News she started having on March 30. The next day she got her first COVID-19 test, which came back positive. It would be Schofield's first test of many — she's had eight more since.
She experienced chills, a headache, difficulty breathing and a fever, she told CTV. After 50 days, she still has some lingering symptoms and is now worried COVID-19 could cause long-term problems. "I still to this day have shortness of breath," Schofield told CTV. "COVID-19 has taken a lot out of me, and it continues every day."
Schofield was hoping she'd be fully recovered by now, nearly two months after her first symptoms, but she has taken a total of nine coronavirus tests and only one came back negative, according to CTV.
Some health care facilities require patients to get two consecutive negative test results at least 24 hours apart to confirm they have cleared the virus.
Schofield says Region of Waterloo Public Health officials released her from self-isolation after 14 days, and she's been cleared to go back to work, too. However, she is still worried she might be contagious.
For those who have had the coronavirus and are waiting to be in the clear, like Schofield, there are still many unknowns about the recovery process.
The CDC says it is possible the virus could be detectable in the upper or lower respiratory tract for weeks after illness onset. However, it says, the "duration of viral shedding and the period of infectiousness for COVID-19 are not yet known."
Schofield says she works in a long-term care setting and doesn't want to put anyone else at risk. The hardest part, she said, is that nobody has answers for her questions.
Dr. Amesh A. Adalja, a senior scholar at Johns Hopkins Center for Health Security, told CBS News that persistent positive coronavirus tests do not necessarily mean the virus is actively persisting inside of a person. "The test isn't detecting viable virus, the test is detecting genetic material from the virus," Adalja said.
"We do know that when people are infected, after they recover they may continue to cough up and excrete viral debris for some period of time," Adalja said. "And it's not necessarily something that reflects infectiousness or contagiousness, although many hospitals and nursing homes require a few negative tests after somebody has recovered in order to clear them."
Adalja said for this reason, there are two different ways recommended by the CDC to determine if a previously infected person can safely leave isolation.
One way is to conduct tests until there are two consecutive negative results, taken no less than 24 hours apart. "Not everybody needs to get this two-test type of protocol; it's usually used for someone being discharged to a nursing home," Adalja said.
The other way to determine recovery is symptom-based. If a patient is without symptoms for seven days and has not had a fever for three days (without relying on fever-reducing medications), then they can be considered recovered, the CDC says.
Adalja did not treat Schofield but said it's likely she doesn't have coronavirus at this point — she had coronavirus. "The test is going to remain positive because there's still viral remnants," Adalja said, adding the test could detect these remnants for weeks at a time for some patients.
As for the possibility of Schofield getting inaccurate test results, Adalja said these tests don't normally produce false positives, but could produce false negatives.
In Schofield's case, Adalja suspects her positive tests are not false. "I suspect she is having viral debris that's still in her nasal passages that's being picked up by the test," he said.
Schofield told CTV she is also concerned about her lingering shortness of breath, and wondering if she'll have to use an inhaler for the rest of her life.
As for her concern about permanent health damage, Adalja says she could be experiencing residual symptoms. "If someone has damage from the virus... their lung function is going to take time to recover, so they may have shortness of breath, but that's not a result of ongoing infection, that might just be the result of the damage the virus did to them earlier in their course of illness," Adalja said.