The aim of this work was to evaluate a dot-enzyme-linked immunosorbent assay (dot-ELISA) using excretorysecretory
antigens from the larval stages of
Toxocara canis
for the diagnosis of toxocariasis. A secondary aim was
to establish the optimal conditions for its use in an area with a high prevalence of human
T. canis infection. The
dot-ELISA test was standardised using different concentrations of the antigen fixed on nitrocellulose paper strips
and increasing dilutions of the serum and conjugate. Both the dot-ELISA and standard ELISA methods were tested in
parallel with the same batch of sera from controls and from individuals living in the problem area. The best results
were obtained with 1.33 μg/mL of antigen, dilutions of 1/80 for the samples and controls and a dilution of 1/5,000
for the anti-human IgG-peroxidase conjugate. All steps of the procedure were performed at room temperature. The
coincidence between ELISA and dot-ELISA was 85% and the kappa index was 0.72. The dot-ELISA test described
here is rapid, easy to perform and does not require expensive equipment. Thus, this test is suitable for the serological
diagnosis of human
T. canis infection in field surveys and in the primary health care centres of endemic regions.
