Recent trends in the diagnosis of toxoplasmosis

Toxoplasma gondii is one of the most widely prevalent cyst forming apicomplexan parasite present worldwide. Felines serve as definitive hosts, while all non-feline vertebrates including humans, act as intermediate hosts of the parasite. There are several serological tests available for the detection of T. gondii antibodies such as the dye test (DT), indirect haemagglutination test (IHA), complement fixation test (CFT), modified agglutination test (MAT), latex agglutination test (LAT), indirect immunofluorescent test (IFAT) and direct agglutination test (DAT). The dye test once considered as gold standard is seldom used nowadays, owing to potent hazardous effects because of involvement of live tachyzoites. Of late, enzyme linked immune sorbent assays (ELISA) have gained a lot of utility in diagnosing toxoplasmosis. Other than serological tests, bioassays, polymerase chain reaction (PCR) based assays and histopathologies are also used. The various tests used for diagnosis of toxoplasmosis, along with various molecules being employed, coupled with their advantages and limitations, are described and discussed in detail in the present review.   Key words: Toxoplasma gondii, diagnosis, enzyme linked immune sorbent assays (ELISA), molecular techniques, polymerase chain reaction (PCR).