[Simultaneous presence of HB-s and anti-HB-s antibody with different specificity in serum].

By means of counterelectrophoresis (CEP) HBs-Ag and anti-HBs were found in the serum of a patient with a third episode of virus hepatitis. Presence of HBs-Ag was confirmed by complement fixation (CF) and immunodiffusion (AGD) but the antibody was not demonstrated by these methods. The subtype of HBsAg in this case was ayw and the antibody was monospecific anti-HBs/d. The presence of HBsAg and anti-HBs differing in specificity was due, probably, to double infection with HB viruses of different subtypes--ayw and adw in this case.