Comparison of three methods for detection of Giardia in dogs and cats

Abstract: Giardia is a parasite that causes disease in both humans and animals all around the world. Approximately 200 million people are infected each year. The parasite is spread mainly through contact with contaminated feces but can also be spread through food and water contaminated with infectious cysts. Symptoms that may occur during infection could be diarrhea and abdominal pain. Not all host organisms get symptoms and there are lots of asymptomatic carriers. The aim of this report was to compare and evaluate the performance of three different methods used to detect Giardia in dogs and cats. Today the gold standard is detecting cysts with immunofluorescence, which was one of the methods evaluated. One cyst visible was enough to say the test was positive. The other two methods were an ELISA and a rapid test, and both detected soluble Giardia antigen. For both methods, color development occurred in case of positive results. The ELISA wells were read spectrophotometrically at 450 nm. During this project, 294 tests from randomly chosen dogs and cats were analyzed. Of all these tests, 103 were analyzed with all three methods, whereas 191 tests were only analyzed with immunofluorescence and ELISA. When analyzing the results, the number of positive test results was very similar between the three methods and there was no statistically significant difference between them. Therefore, when price, time and results were taken into consideration, the method recommended was ELISA.