Dangerous blood clots pose a perplexing coronavirus threat

First came a high fever, drenching sweats and muscle aches. Then, almost a month later, a weird numbness that spread down the right side of her body.

Darlene Gildersleeve thought she had recovered from COVID-19. Doctors said she just needed rest. And for several days, no one suspected her worsening symptoms were related — until a May 4 video call, when her physician heard her slurred speech and consulted a specialist.

“You’ve had two strokes,’’ a neurologist told her at the hospital. The Hopkinton, New Hampshire, mother of three is only 43.

Blood clots that can cause strokes, heart attacks and dangerous blockages in the legs and lungs are increasingly being found in COVID-19 patients, including some children. Even tiny clots that can damage tissue throughout the body have been seen in hospitalized patients and in autopsies, confounding doctors’ understanding of what was once considered mainly a respiratory infection.

“I have to be humble and say I don’t know what’s going on there, but boy we need to find that out because unless you know what the pathogenic (disease-causing) mechanism is, it’s going to be tough to do intervention,” Dr. Anthony Fauci, the nation’s top infectious disease expert, remarked during a medical journal interview last month.

Doctors and scientists at dozens of hospitals and universities around the globe are seeking answers while trying to measure virus patients’ risks for clots and testing drugs to treat or prevent them.

Gildersleeve said health authorities “need to put out an urgent warning about strokes” and coronavirus. Not knowing the possible link “made me doubt myself” when symptoms appeared, she said.

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