[Outbreak of follicular conjunctivitis caused by adenovirus in a geriatric centre]

Adenovirus serotype 4a is a respiratory virus that occasionally causes conjunctivitis. This paper describes an outbreak of follicular conjunctivitis that occurred in a geriatric centre.

Outbreak description and epidemiological research through a survey. For the microbiological study conjunctival swabs were collected using viral and bacterial transport media. Adenovirus was detected by real-time polymerase chain reaction. The serotype was determined by sequencing of a fragment of the hexon and E1 genes.

In autumn 2008 an outbreak of follicular conjunctivitis caused by adenovirus serotype 4a was detected. Twenty three percent 23% (69/300) of residents and 5% (9/180) of workers in a geriatric centre in Gipuzkoa were affected. The clinical symptoms were of prolonged duration (11±5 days). The temporal association of the cases suggested transmission from person to person. The sanitary measures established (asepsis and frequent hand washing, cleaning and disinfection of objects and surfaces) were effective, interrupting the transmission of the disease within a short period of time.

Rapid detection, identification of the causative agent and implementing appropriate control measures can significantly reduce the impact on both health and economic costs of these outbreaks.