A retrospective study was conducted to identify the epidemiologic characteristics of invasive pneumococcal infections among children <14 y of age in our geographic region. During a 5-y period, from 1995 to 1999, 590 cases of invasive pneumococcal infection were identified in Aghia Sophia Children's Hospital, Athens, Greece. The male to female ratio was 1.4:1 and 64% of patients were younger than 5 y of age. The overall annual incidence rate was estimated as 44/100,000 children <14y of age, whereas the incidence rate for children <5y of age was 100/100,000. The most common types of infections were pneumonia (472 cases; 133 definite and 339 probable), bacteraemia without focus (79 cases), and meningitis (33 cases). A seasonal variation of invasive pneumococcal infections was noted, with two peaks--one during spring and the other during autumn. Only two cases with meningitis died and one developed permanent neurological sequelae, representing a case-fatality rate for meningitis of 6%. Serogroups 14, 19, 6, 18, 23, 4 and 9 were the most prevalent, comprising 77% of 92 serotyped isolates.
Conclusion: Invasive pneumococcal infections cause considerable morbidity in the paediatric population in the Athens metropolitan area. Sixty-six percent of the serotypes causing invasive pneumococcal disease in our region are included in the 7-valent conjugate vaccine.