Outbreak of human adenovirus type 3 infection in a pediatric long-term care facility--Illinois, 2005.

BACKGROUND

Human adenovirus type 3 (HAdV-3) causes severe respiratory illness in children, but outbreaks in long-term care facilities have not been frequently reported. We describe an outbreak of HAdV-3 infection in a long-term care facility for children with severe neurologic impairment, where only 3 of 63 residents were ambulatory.

METHODS

A clinical case of HAdV-3 was defined as fever (temperature, > or = 38.0 degrees C) and either a worsening of respiratory symptoms or conjunctivitis in a resident, with illness onset from June through August 2005. We reviewed medical records; conducted surveillance for fever, conjunctivitis, and respiratory symptoms; and collected nasopharyngeal and conjunctival specimens from symptomatic residents. Specimens were cultured in HAdV-permissive cell lines or were analyzed by HAdV-specific polymerase chain reaction assay.

RESULTS

Thirty-five (56%) of 63 residents had illnesses that met the case definition; 17 patients (49%) were admitted to intensive care units, and 2 (6%) died. Patients were hospitalized in the intensive care unit for a total of 233 patient-days. Illness onset dates ranged from 1 June through 24 August 2005. Thirty-two patients (91%) had respiratory infection, and 3 (9%) had conjunctivitis. HAdV was identified by culture or PCR in 20 patients. Nine isolates were characterized as HAdV-3 genome type a2.

CONCLUSIONS

Considering the limited mobility of residents and their reliance on respiratory care, transmission of HAdV-3 infection during this outbreak likely occurred through respiratory care provided by staff. In environments where patients with susceptible underlying conditions reside, HAdV infection should be considered when patients are identified with worsening respiratory disease, and rapid diagnostic tests for HAdV infection should be readily available to help identify and curtail the spread of this pathogen.