Introduction: Trichinellosis is a helminth infection having a wide geographical distribution. It is acquired by ingestion of raw or undercooked meat infected with Trichinella spp. The present work reviews the human trichinellosis outbreaks recorded in Spain during 1990-2001, taking into account both the geographical distribution and source of the infection.
Methods: The parasite was isolated from suspected meats with the digestion technique. Molecular characterization of Trichinella isolates was done by random amplified polymorphic DNA (RAPD) analysis and Western-blot with US5 and US9 monoclonal antibodies. Anti-Trichinella antibodies in the patients' sera were investigated by indirect immunofluorescence (IIF).
Results: A total of 49 trichinellosis outbreaks were detected in Spain during 1990-2001, 75.5% produced by ingestion of infected wild boar, 14.3% by infected domestic pig and 10.2% by an unknown source. Of the 49 outbreaks, 21 were followed up in our laboratory. We were able to perform molecular identification of the Trichinella species involved in 13 outbreaks, with 61.5% produced by T. britovi and 38.5% by T. spiralis. Serological diagnosis of the trichinellosis patients by IIF allowed confirmation of helminth infection.
Conclusions: With the use of molecular markers, T. spiralis and T. britovi were identified as the causative organisms in trichinellosis outbreaks detected in Spain during 1990-2001. These results reveal the importance of T. britovi in Spanish public health.