Boyden's tannic acid hemagglutination test (HA) and a bentonite flocculation test (BF) were evaluated for the detection of echinococcus disease in sera from 30 clinically diagnosed patients. In addition, the sensitivity of the test was evaluated with 246 sera from nonechinococcus individuals.
The HA test was slightly more sensitive (96.6% of 30 sera) than the BF test (90.0% of 30 sera) in the detection of positive clinical echinococcus infections. In the titration of 246 nonechinococcus sera 14.2 per cent gave positive results with the HA test (titers of 1:50 or 1:100 in most instances). With the BF test 10.1 per cent of these sera were positive. The CF test was positive in only 36.3 per cent of 22 sera from patients with active infections of echinococcosis but showed no cross reactions with the nonechinococcus sera tested.
A positive HA test and a positive BF test given by a serum from a case clinically diagnosed as echinococcosus, constitute presumptive evidence for the presence of echinococcus disease.