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Severely immunosuppressed people can battle #SARSCoV2 for months. Some virologists are convinced the #variants emerged in this setting. My latest for @JAMA_current deals with how to care for these vulnerable patients, who may not respond to vaccines. https://bit.ly/2RE5xB2
Their long infections and suboptimal therapies can provide the time + evolutionary pressure for variants to emerge. The fear: These changes could produce a more transmissible virus, like B.1.1.7, or one that resists therapies or vaccines, as may be true for B.1.351 and P.1.
Case reports with genomic sequencing show the virus evolving within severely immunocompromised hosts. An apparent factor: convalescent plasma, which may keep patients alive without knocking out the virus.
Meanwhile, all signs indicate these patients can be contagious for months. So! How can docs best treat their #COVID19 without encouraging treatment-resistant variants to emerge? And how long must these folks be isolated?
One lesson: IF used, convalescent plasma should be high titer and given early in the course of infection, when the antibodies it contains are more likely to fully block viral replication and evolution. “Don’t just give it because it’s available” or as “a Hail Mary pass.”
Researchers are interested in using monoclonal antibodies prophylactically in these patients. Regardless, family members and caregivers MUST be vaccinated to create a “bubble” around people with severely weakened immune systems.
Some case reports... A man in his 70s w/marginal B-cell lymphoma actively infected for more than 100 days. 23 samples, starting with the first positive swab, showed the virus evolving + adapting to treatment. Patient developed a double mutant variant. https://go.nature.com/2RDELIH
A man in his 70s w/ CAR-T therapy for treatment–resistant multiple myeloma. Infectious virus in endotracheal aspirate 72 days after #COVID19 diagnosis. Sequencing found that 5 variants emerged after his initial infection. https://bit.ly/3nW5nRk
60-year-old man w/ refractory mantle cell lymphoma. Hospitalized 3 times for #COVID19 and was infectious for at least 119 days. https://bit.ly/3b8ObCU
Links to more case reports in my story. Featuring @GuptaR_lab @Cambridge_Uni, John Mellors + @cleverwebber @UPMC @PittTweet, @DocSaimaAslam @UCSanDiego, @JoshuaHillMD @fredhutch, @LauringLab @UMich, and the late @FranciscoMarty_ @BrighamWomens.
Related from @JAMA_current this week: 46% of 658 solid organ transplant recipients had no antibody response after both #COVID19 mRNA vaccine doses. https://bit.ly/3utv0eZ
