The Centers for Disease Control and Prevention issued a national Health Alert Network advisory on Aug. 11 warning that patients taking B cell-depleting or B cell-modulating medications, particularly the anti-CD20 monoclonal antibodies used for lymphoma, multiple sclerosis, and several autoimmune conditions, face unusually severe outcomes if they contract a mosquito- or tick-borne virus that reaches the brain.
The figure at the center of the advisory is stark. Among published case reports of arboviral neuroinvasive disease in patients on anti-CD20 monoclonal antibodies, overall mortality was approximately 40 percent, and most survivors experienced long-term neurologic damage, the CDC said. West Nile virus was the most commonly reported virus.
