‘False dawn’ recovery haunts survivors who fall sick again
TOKYO — It had been more than a month since Mirabai NicholsonMcKellar was infected with the novel coronavirus, and the 35year-old filmmaker thought she was on her way to recovery. Then the shortness of breath came back, followed by chest pains.
A visit to the emergency room and a second test for COVID-19 gave another positive result. Just three days earlier, she’d been cleared by health authorities in Australia’s New South Wales state and was allowed to end her home quarantine after going 72 hours without symptoms.
“When is this going to end? I think about that constantly,” she said of the twists and turns in her health. “Am I still contagious? How do I know if I’m not contagious?”
Her experience adds to a growing number of reports of patients appearing to have a reactivation of symptoms, testing positive again or even potentially being reinfected. Such incidents don’t align with the generally accepted understanding of how virus infections work and spread.
This so-called false-dawn phenomenon is puzzling health experts as they try to come to grips with the mysterious pathogen that emerged five months ago. Solving the puzzle will inform a broad range of challenges, from the development of an effective vaccine to how soon governments may be able to safely end lockdowns and allow normal life to resume.
So far, there hasn’t been enough research to conclude why symptoms seem to re-emerge in some people, and whether they experience reinfection or if the virus persists for weeks. One possibility is that COVID-19 causes blood clots that may cause potentially dangerous complications unless treated with anticoagulant medications, said Edwin J.R. van Beek, chair of clinical radiology at the University of Edinburgh’s Queens Medical Research Institute.
South Korean researchers also offered some clues this week when they reported that so-called nucleic acid tests might be positive based on the detection of dead viral particles that could give the false impression that a patient is still infectious when they’re not.
“Everyone’s trying to figure this out,” said Yvonne Maldonado, an infectious diseases professor at Stanford Medical School. “What happens when people have been sick and infected — are we going to consider them immune and, therefore, not susceptible at all? Or are they immune and serve as potential points of infection for other people?”
As the number of recovered patients expands, the burden will begin to shift down the medical practice chain, said Michelle Biehl, a critical care pulmonary doctor at Cleveland Clinic in Ohio. More primary care doctors, mental health specialists and physical therapists will be seeing survivors.
“You send them home and what happens then?” asked Maldonado. “From the outpatient side, we’re just starting to get to that point where we’re seeing people in the longer term.”
There’s consensus that so-called herd immunity is key to ending the pandemic, but with a vaccine unlikely to be widely available this year, it will depend on factors such as how long people who’ve recovered have immunity and what percentage of people must be immune to protect the “herd.”
There are “a lot of unknowns and uncertainty in the development of individual immunity,” said Kentaro Iwata, a professor of infectious diseases at Japan’s Kobe University. “Development of antibody inside the body is not necessarily development of immunity against this disease.”
The unknowns concerning infectiousness, immunity and lingering symptoms create frustrating dilemmas for patients such as Daniela Alves. The London resident paid 200 pounds ($251) for a private test that told her she was positive. Like Nicholson-McKellar, she was never hospitalized but had coughs, shortness of breath and aches that came and went for weeks, never in a straight path toward recuperating, leaving her uncertain of the state of her health.
“I don’t know when I’m going to be negative so I can go outside,” she said. “Do I have to pay another 200 pounds so I know I’m safe to others?”