Cuban Ocular Toxoplasmosis Epidemiology Study (COTES): incidence and prevalence of ocular toxoplasmosis in Central Cuba

Background Serological studies indicate that rates of ocular toxoplasmosis (OT) vary geographically, with higher rates in tropical regions. Little is known about population-based rates of active OT. We aimed to describe the epidemiology of OT in Central Cuba. Methods This large-population, cross-sectional cohort study used a prospective database at a large regional referral centre in Central Cuba. The patient database was searched for all patients who presented with OT during the 12-month study period from 1 April 2011 to 31 March 2012. Inclusion criteria were the clinical diagnosis of OT, characterised by focal retinochoroidal inflammation and a response to therapy as expected. Gender-stratified and age-stratified study population data from the 2012 Cuban Census were used to calculate incidence rates and prevalence ratios. Results Among 279 identified patients with OT, 158 presented with active OT. Of these, 122 new-onset and 36 prior-onset cases were confirmed. Based on the total population in the Sancti Spiritus province (466 106 persons), the overall incidence of active OT was 26.2 per 100 000 person-years (95% CI 21.7 to 31.3) with an annual prevalence ratio of 33.9 per 100 000 persons (95% CI 28.8 to 39.6). The incidence of active OT was lowest in the oldest age group and highest in patients aged 25-44 years (4.5 and 42.1 per 100 000 person-years, respectively). Conclusions This first report describing population-based rates of OT in the Cuban population highlights the importance of patient age as a likely risk factor for OT. Disease rates were found to be highest in females and young to middle-aged adults.