In addition, chronic arthritis secondary to " S . flexneri " infection, called reactive arthritis, may be caused by a bacterial antigen; the occurrence of this syndrome is strongly linked to HLA-B27 genotype, but the immunologic basis of this reaction is not understood.
42.
When the National Vaccine Advisory Committee of the Food and Drug Administration certified the drug in December for people 16 to 70 years old, members appended a list of concerns about the long-term effect of the vaccine, especially among those with chronic arthritis or heart conditions.
