[ad_1]
Another group, writing in The New England Journal of Medicine Earlier this month, he detailed the trajectory of the virus in a 45-year-old man with an autoimmune disorder for which he was receiving immunosuppressants. In this case, they found that there was an “accelerated” evolution of the virus in the individual, and many of the mutations were in the spike protein. Most immunosuppressed people clear SARS-CoV-2 infections without major complications, they wrote, but “this case highlights the potential for persistent infection and accelerated viral progression associated with an immunosuppressed state.”
The same phenomenon has been observed in other conditions where the immune system is hampered. HIV attacks immune function, allowing it to evolve at a staggeringly high rate, making it even more difficult for the body to keep producing antibodies that bind and neutralize the virus. By the same mechanism, HIV infections allow other viruses in the individual to last longer and transform. The herpes simplex virus can develop unusual drug resistance in AIDS patients, for example.
Still, we need a better understanding of exactly which immunosuppressed patients are most vulnerable to prolonged SARS-CoV-2 infection. The “immunosuppressed” category captures a wide range of different conditions, and not all may confer the same persistent Covid-19 risk. Brian Wasik, a virologist at Cornell University, notes that the term can include people born with rare disorders that decrease their ability to fight pathogens, as well as those who take immunosuppressants to allow a transplant or quell an autoimmune disease.
The evidence for links between immunosuppressed individuals and persistent SARS-CoV-2 infections, and between persistent infections and viral evolution, is compelling enough to be considered in discussions of vaccine priority. On Sunday, a panel from the US Centers for Disease Control and Prevention recommended that immunosuppressed people be placed in “Phase 1c,” the third wave, of vaccine launch. That means they must receive the injections at the same time as people with cancer, coronary heart disease or obesity, among other conditions. That decision was meant to address the particular risks that Covid-19 poses for people with immune system problems, but it set aside the possibility that vaccinating these people could help prevent the development of new variants of SARS-CoV- 2 that would make this pandemic even more serious. worse than it already is. For that reason, although there are only a handful of directly relevant case reports, public health officials should consult with virologists on whether it would be prudent to transfer immunosuppressed individuals to the previous Phase 1b group.
At the very least, we need better monitoring of possible changes in SARS-CoV-2. The United States government should do more to help organize viral sequencing efforts. The CDC has a program dubbed Spheres that has tried to capture sequence data during the pandemic, but is falling short: Where the UK has sequenced roughly 10 percent of its Covid-19 cases, the US has only managed 0. , 3 percent. “It’s a bit spotty,” says Adam Lauring of the University of Michigan School of Medicine, adding that his team has uploaded about 2 percent of the sequence variant data in the US “There are vast areas of the country where there are no people who dedicate a lot of time and effort ”to this task. Better tracking of viral evolution could also help clarify the question of where exactly, in which sick people, these changes are most likely to accumulate.
As we monitor for SARS-CoV-2 mutations, we must recognize that understanding their epidemiological and clinical importance requires more work. Meanwhile, the virus continues to proliferate, giving it more opportunities to mutate even as it spreads from person to person. But long-term infections in some immunosuppressed individuals, and the associated potential for viral evolution, should be a focus of attention.
More from WIRED in Covid-19
