Investigation and management of an outbreak of ocular adenovirus infections: a New Zealand experience

Abstract

Nosocomial ocular infections are uncommon (Durand et al, 2004), though they do occur both as sporadic cases and as outbreaks. A common viral cause of these cases and outbreaks is adenovirus, which has also caused epidemics of keratoconjunctivitis. Adenovirus has been shown to remain viable on environmental surfaces for extended periods and thus can be transmitted by hospital equipment. Many patients presenting to ophthalmology clinics require contact with the specialised equipment used for examinations within the department. As with all hospital equipment and surfaces, thorough cleaning and disinfection is essential between patients. Following an unexpected increase in the number of adenovirus type 19 isolates from eye swabs taken from patients being seen on the second or subsequent appointment in the eye outpatient's department of the Canterbury District Health Board in New Zealand, the infection control service undertook a review of the area and practices, including the cleaning and disinfecting processes, within the department. As this was the first such outbreak within the organisation, the investigation included a literature review of ocular adenovirus infections and outbreaks worldwide. Recommendations made included an enhanced cleaning protocol for tonometer tips, better cleaning of the environment and improvements in the implementation of standard precautions by staff. Following the introduction of these changes, rates of adenoviral eye infections returned to pre-outbreak levels.