Evaluation of soluble-antigen fluorescent antibody test for antibodies to Trichinella spiralis in Experimentallly infected swine.

The soluble-antigen fluorescent antibody (SAFA) test was evaluated at intervals from 7 days to 1 year in 42 swine infected with 25, 100, 500, 2,500, 12,000, or 250,000 Trichinella spiralis larvae. Serums were test positive as early as 14 days after exposure in swine fed 25 larvae and as early as 7 days in swine fed 100 or 500 larvae. Serums of all swine fed larger numbers of larvae were test positive by day 17 and remained test positive for the duration of the experiment. Fluorescence obtained in tests of serums from noninfected, laboratory-raised swine varied significantly; field tests were not done. The test couldbe done with whole heparinized blood, dried blood, or serum eluted from paper disks. Time required for the test procedure was reduced to approximately 45 minutes. The SAFA test detected antibodies to T spiralis earlier in swine fed smaller numbers of larvae and for longer duration than any other serotest which has been evaluated in swine. The test, particularly if automated, seems adequate as a mass screening test for surveillance and control of trichinosis in swine.