Rotavirus infection among children with diarrhoea in Italy

Despite the absence of a nationwide surveillance system for rotavirus infec tion, relevant information concerning the epidemiology of this pathogen in Italy can be obtained from hospital-based studies carried out since the ear ly 1980s on patients with acute diarrhoea. A review of more than 50 papers and congress proceedings published in both international and national liter ature indicates that rotavirus is the most important cause of diarrhoea in Italy among young children requiring hospitalization, with a prevalence ran ging from approximately 20% to 40% in different studies. Infection is predo minant among children aged 6-24 months, although cases are also common in y ounger children and in children 2-3 y of age. Despite differences among stu dies in geographical area, years and age group under investigation, an incr ease in rotavirus cases is consistently reported in the winter months, with a peak in February through April. Although a few studies have been conduct ed in non-hospitalized patients, rotavirus infection is significantly less frequent among outpatients with enteritis than among inpatients. Most circu lating rotavirus strains typed from 1981 to 1992 belong to serotype 1 and, to a lesser extent, 4. However, untypable rotavirus strains have been found in these years, with prevalences up to 27%, suggesting a possible spread o f non-serotype 1 through 4 strains.