Fusarium and Acanthamoeba keratitis: can a single centre detect outbreaks?

The Centers for Disease Control (CDC) recently reported nationwide epidemics of Fusarium and Acanthamoeba keratitis. 1 2 These investigations were prompted by reports of increased cases at individual sites. 3 - 5 It can be difficult to detect outbreaks at a single centre due to changing diagnostic criteria, changing referral patterns, and the effects of chance. The reason for the recent increase in Acanthamoeba keratitis is unknown, but possibilities include contaminated tap water and the use of certain contact lens solutions. 2 3 5 It is possible for a single centre to detect an outbreak, but institutions need to be wary of changing referral patterns and diagnostic criteria.