[Prevalence of the Epstein-Barr virus among different populations in the central area].

In order to estimate the seroprevalence of the Epstein-Barr virus in the centre area, a serological study is carried out using the indirect immunofluorescence technique on 759 supposed healthy people, from both sexes and with ages between 6 months and 50 years, 565 from which were living in urban areas (Madrid and Guadalajara city) and 194 in rural areas (Arganda del Rey, Madrid) and Chiloeches (Guadalajara). Global seroprevalence was of 81% in Madrid city, 90% in Guadalajara city and 85% in both rural populations. Comparing groups of the same age, we have not found any statistically significant differences between the urban (86%) and the rural (85%) areas. Neither we have found any relation between seropositivity and sex (74.7% for women and 81% for men). On the other hand, we observed that in our study group, seroprevalence was related to socioeconomic status--the higher the antibody percentages, the lower the socioeconomic status, both in the rural and in the urban areas (p less than 0.001)-- and age antibody percentages increased with age, with p less than 0.025 for urban areas and p less than 0.05 for rural areas.