Use of in vivo challenge to assess rubella immunity determined by haemagglutination inhibition and latex agglutination.
In order to estimate the protection afforded by low levels of rubella antibody, pregnant women were tested by haemagglutination inhibition (HAI) and latex agglutination (LA). Fifty-nine women whose sera were HAI-negative (less than 25 IU/ml) or weakly positive (25 IU/ml) received rubella vaccine (RA 27/3) after delivery. Serum samples were collected one week and one month after immunization and tested for rubella total antibody and rubella IgM and IgA antibody. No patients found positive by HAI and LA showed any evidence of primary immunization. Furthermore, rubella IgM antibody was never detected after immunization in women who were HAI-negative and LA-positive during pregnancy. These results show that low antibody titres detected by LA are sufficient to protect individuals against infection with the attenuated virus. It is conceivable that such low titres also ensure protection against natural rubella infection.
Grangeot-Keros
L
L
Department of Microbiology and Immunology, Hôpital Antoine Béclère, Clamart, France.
Badur
S
S
Pons
J C
JC
Duthu
S
S
Pillot
J
J
D000914:Antibodies, Viral; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007841:Latex Fixation Tests; D011237:Predictive Value of Tests; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology*; D011933:Reagent Kits, Diagnostic; D012409:Rubella / Q000276:immunology*; D012412:Rubella virus / Q000276:immunology*
D000914:Antibodies, Viral; D007070:Immunoglobulin A; D007075:Immunoglobulin M; D011933:Reagent Kits, Diagnostic; C040901:rubella antibodies