Among the 100 million people around the world who have battled coronavirus infections, scientists are turning to the case of a 45-year-old COVID-19 patient in Boston to understand how the virus is able to outwit humans.
During his 154-day illness — one of the longest on record — the patient’s body became a crucible of riotous viral mutation. He offered the world one of the first sightings of a key mutation in the virus’ spike protein that set off alarm bells when it was later found in strains in the United Kingdom, South Africa and Brazil.
In the U.K. strain, the genetic change known as N501Y is thought to help enhance the virus’ transmissibility by about 50%. In the South Africa strain, it may reduce the effectiveness of COVID-19 vaccines and treatments. Tests of its effect on the Brazil variant are still in progress.
The Boston patient is now being viewed as an important harbinger of the coronavirus’ ability to spin off new and more dangerous versions of itself. Although he died over the summer, the medical file he left behind is helping experts anticipate the emergence of new strains by focusing on the role of a growing population of patients with compromised immune systems who battle the virus for months.
Among the sickest of COVID-19 patients, this population of “long haulers” appears to play a key role in incubating new variants of coronavirus, some of which could change the trajectory of the pandemic.
The mutations that arose from this single patient are “a microcosm of the viral evolution we’re seeing globally,” said Dr. Jonathan Z. Li, an infectious disease specialist at Brigham and Women’s Hospital in Boston who treated him. “He showed us what could happen” when a germ with a knack for genetic shape-shifting stumbles upon conditions that reward it for doing so.
Indeed, situations where patients can’t clear a viral infection are “the worst possible scenario for developing mutations,” said Dr. Bruce Walker, an immunologist and founding director of the Ragon Institute in Boston.