Table 2.

Advantages and limitations of indirect and sandwich ELISA methods in the immunodiagnosis of ruminant fascioliasis

	Indirect ELISAs (detection of antibodies)	Sandwich ELISA (detection of antigens)
Advantages	Demonstrates effective immunodiagnostic performance with high sensitivities and specificities (19, 23, 32) Recombinant CL ELISA is the most favourable antigen in serodiagnosis among other recombinant and native proteins evaluated (25) 100% sensitivity and specificity in prepatent serodiagnosis (16)	Excellent sensitivity and specificity Correlates with fluke burden (34) Accurately reflects the presence of ongoing infection Monoclonal antibodies shorten detection time (from day 1 of post-infection) (40) Monoclonal antibodies reduce variations common in polyclonal antibody ELISA
Limitations	Inability to distinguish active infection from past exposure to the parasite	Coproantigens detection is longer (from 6 weeks post-infection) Varying degree of cross-reactivity is seen