[Clinico-epidemiologic study of human listeriosis in Barcelona (1990-1991)]

The aim of this study was to determine the incidence of human listeriosis in Barcelona in addition to its clinical form of presentation, seasonability, risk groups and evolution.

A prospective study of the cases of listeriosis registered in the city of Barcelona, Spain (population of 1,643,542 inhabitants) over the period from January 1, 1990 to December 31, 1991 was carried out.

Fifty-five cases were reviewed with a global rate of incidence of listeriosis of 9.4 per one million inhabitants per year with predominance being observed in the summer months (39% in 1990, 42% in 1991). Ninety-one percent of the cases were observed in non pregnant adults, with 86% of the patients being immunosuppressed. Nosocomial listeriosis, diagnosed in 23 patients (42%), was predominant in the group with immunosuppressive treatment (p = 0.0005). The main site of isolation was blood in 45 cases (82%), in the form of primary listeriosis (p < 0.0005). Global mortality was 49%, being greater in the group of patients with nosocomial infection (p = 0.01) and with primary bacteremia (p < 0.001). No patients without known risk factors or pertaining to the perinatal group have died.

The use of an active system of registration of listeriosis facilitates better knowledge of its incidence, distribution and infection pattern thus allowing the early detection of epidemic outbreaks with the aim of controlling such an infection, given the social implications and morbidity of this disease.