The clear bias toward IgA and the fact that MTB‐specific IgA and IgG memory B cells can be isolated from the peripheral blood of healthy TB‐exposed HCW—as demonstrated for anti‐HBHA memory B cells—suggests that the anti‐MTB B‐cell response spreads from the lung to the periphery independently of active TB disease. The gene discussed is CD79A; the disease is tuberculosis.