Detection of toxoplasmic immunity by multipuncture skin test with excretory-secretory antigen.

In 414 volunteers the sensitivity and specificity of a multipuncture skin test with excretory-secretory (ES) toxoplasma antigen was compared with serological detection by an indirect fluorescent antibody (IFA) test. The ES antigen was extracted from supernatants of cell cultures infected with Toxoplasma gondii, purified, and standardised, and the antigen used met current safety standards. The correlation between the skin test and IFA result was 94.2% (97.8% when the skin test was repeated 30 days later). No false-positive skin tests were noted. The skin test did not transform an originally negative serological test into a positive one. In programmes to prevent congenital toxoplasmosis, this sensitive, specific, and inexpensive skin test can be widely used for the detection of immunity to toxoplasma in women before their first pregnancy.