[Epidemiology of gastroenteritis by Salmonella (1983-1994)]

The incidence of Salmonella enteritidis infection has been study in order to determine their epidemic spread from 1983 to 1994, and the impact of the measures introduced to attempt its control.

Review of the stool cultures positives for enteric pathogens obtained in the Hospital de Navarra from 1983-1994.

Looking at the isolation rates of the different enteric pathogens from 1983 to 1994, a sharp increase of S. enteritidis was recorded on 1985 as a consequence of several outbreaks associated with the consumption of mayonnaise elaborated with row eggs. From 409 strains of Salmonella isolated that year, 302 were serotype enteritidis, this means a 7.5 fold rise since the preceding year in which the prevailing serotype was S typhimurium. From 1985 through 1991 the incidence of S. enteritidis stand high, and pick again on 1990. Since then, a decline has been observed, and in 1994 the number of Salmonella cases recorded were about those on 1984, however, S. enteritidis is now the prevailing serotype.

The egg-borne S. enteritidis epidemic emerged as a major public health problem in Navarra in 1995, associated to the consumption of home made mayonnaise. The measures introduced by local Public Health authorities to attempt control of non pasteurized mayonnaise were insufficient. Evidence from other places links human infections to vertical transmission from breeding flocks to layers. And makes of S. enteritidis infection an international challenge. The severity of the lived experience demands a time-temperature control of eggs in the interval from purchaser to consumer and a more generalized use of pasteurized egg products, no only in the industry but also in the household.