An outbreak of Hemophylus influenzae infection among residents in an insurance care facility for the elderly

Aim: To study the epidemics of the hemophilus influenzae (HI) infection in the summer, 2005 among 46 residents in the second floor of our insurance care facility, Mam Cuore. Methods: The spreading pattern of HI infection, antibiotic susceptibility and serological identification of HI isolated from sputum culture were investigated, and underlying diseases, functional disorders, body weight, age, sex, ADL- and dementia-scores were compared among patients with the non-symptomatic group, HI infection and severe HI pneumonia groups. Results: Lower ADL and body weight were noted to suffer significantly more HI infection and severe pneumonia. Furthermore, stroke patients tended to suffer more HI infection. Dementia patients suffered significantly more severe pneumonia. Residents of rooms close to the room of original patient showed symptoms earlier than patients in more distant rooms. While the numbers of patients with HI infection were 15 (60%) and 10 (40%) before and after the first isolation of HI, 5 out of 15 patients (33%) and one out of 10 patients (10%) progressed to severe pneumonia, respectively. Although these results did not have statistical significance, they suggests that rapid assessment and therapy of HI infection tended to prevent aggravation. Non-typeable strains were detected and were all β-lactamase nonproducing ampicillin resistant (BLNAR) without susceptibilities to cefaclor (CCL) and cefdinir (CFDN). Preceding the epidemic, an outbreak of the common cold syndrome was recognized. Conclusion: Assessing elderly patients suspected of the HI infection, and organized management for treatment are essential to improving outcome.