ABSTRACT
Taenia solium is endemic in the Andean region of Ecuador. The recent rediscovery of Taenia saginata in humans urges to reconsider some assumptions in relation to the epidemiology of the taeniosis/cysticercosis complex in this country.Therefore, data were compiled on the infection of both tapeworms in man and animals in Pichincha and Imbabura provinces in the Andean region, north of Quito. On post mortem inspection 3 out of 806 (0.37%) carcasses had T. saginata metacestodes, however, 35 sera out of 869 (4.03%) showed circulating antigen in a monoclonal antibody-based sandwich ELISA (Ag-ELISA). Porcine cysticercosis was detected in 15 out of 2896 (0.52%) carcasses and 93 out of 1032 serum samples (9.01%) were positive in Ag-ELISA. In humans, 4.99% (215 out of 4306) cases of antigen positives were found, whereas coprological examination of 1935 stools resulted in 30 positive cases (1.55%). The limited number of adult tapeworms (29) that were collected does not allow firm conclusions on the proportion of each species, but in total 21 specimen were identified as T. saginata and 8 as T. solium. These data have been discussed in view of the epidemiology of human cysticercosis.
Subject(s)
Cattle Diseases/epidemiology , Swine Diseases/epidemiology , Taenia saginata/isolation & purification , Taenia solium/isolation & purification , Taeniasis/epidemiology , Zoonoses/epidemiology , Animals , Antibodies, Helminth/blood , Antibodies, Monoclonal/blood , Antigens, Helminth/immunology , Cattle , Cattle Diseases/parasitology , Cysticercosis/epidemiology , Disease Reservoirs/veterinary , Ecuador/epidemiology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Public Health , Seroepidemiologic Studies , Swine , Swine Diseases/parasitology , Taenia saginata/immunology , Taenia solium/immunologyABSTRACT
Given the constraints of classical diagnostic methods, i.e., morphological and isoenzymatic studies of proglottids, a polymerase chain reaction test complemented with restriction enzyme analysis has been modified by redesigning one of the primers to reduce nonspecific amplifications experienced when using field samples. The use of these new, highly cestode-specific primers and the restriction enzyme Ddel led to the development of a diagnostic assay that clearly distinguishes between Taenia saginata and T. solium proglottids in field samples. This assay confirms the presence of T. saginata in Ecuador. DNA amplification of some of these taeniids showed different patterns, suggesting the possibility that strain differences exist. These results demonstrate the need for development of useful molecular assays as reliable tools for epidemiological studies on cestodes.