Four cases of trichinosis found in a family living in Iztapalapa, Mexico, D.F. are reported. The family reported to frequently eat raw sausage originally from Villanueva, Zacatecas from which Trichinella spiralis larvae were isolated. Diagnosis was difficult in the first case since no epidemiological history was associated with the patient, besides the fact that the patient showed no signs of eosinophilia and blood tests were negative. The diagnosis in this case was confirmed through muscular biopsy. The predominating symptomatology consisted in the trilogy of fever, eyelid edema and myalgias.