A third outbreak of Trichinella britovi with 140 people involved, occurred in Granada Spain (December 1998). The source of infection was sausage made from uninspected wild boar meat. Fifty-two patients agreed to participated in this study. An elevated eosinophil level (> 5%) was detected in 59.6% of patients, and persisted in most of these cases for two months. A moderate IgG response was observed. At the onset of symptoms, Western blot (WB) test detected more positive cases than Enzyme linked immunosorbent assay (ELISA) and indirect immunofluorescence (IIF). Six months from infection, ELISA revealed fewer positive cases than the other two tests. It would appear that the response to somatic antigens starts earlier than those to cuticular and excretory/secretory (ES) antigens and that the response to ES antigens is the first to decrease.