In 1997 people older than 60 years represented the 7,1% of the Costa Rican population.  In the past the majority of survey studies on intestinal parasites centered in pediatric or general populations.  We have conducted a survey of the previously overlooked elderly population. Fecal samples from 151 elderly patients (older than 60 years) from the outpatient clinics of the Raúl Blanco Cervantes Hospital were analyzed by means of direct smears, Kato and Baermann methods, cool Ziel-Neelsen and Giemsa stains. We found 8 samples positive for Giardia, 8 positive for Cryptosporidium, representing a prevalence of 5,3%, respectively.  We also found microsporidia (2,6%) and Entamoeba histolytical dispar (2%).  Forty patients had at least one parasite, including intestinal protozoa or helmints, showing a prevalence of 26,5%. The last national survey of intestinal parasites realizard in Costa Rica in 1996 showed a prevalence of 21%.  Ih this study we show a prevalence of 26,5%, including 5,3% of cases of Cryptosporidium, 2,6% of microsporidium, and 2% of S. stercoralls. These parasites were not investigated in the National survey.  In older patients, the presence of S. stercoralls is noteworthy, since it is related to chronic infection, sometimes spanning several decades.  Thus, we recomended the application of the more sensitive Baermann method in coproparasitologic studies, means in elderly oppulations.

elderly; intestinal parasitism; Strongyloides ; Baermann method