A New Method to Predict the Epidemiology of Fungal Keratitis by Monitoring the Sales Distribution of Antifungal Eye Drops in Brazil

Abstract

PurposeFungi are a major cause of keratitis, although few medications are licensed for their treatment. The aim of this study is to observe the variation in commercialisation of antifungal eye drops, and to predict the seasonal distribution of fungal keratitis in Brazil.MethodsData from a retrospective study of antifungal eye drops sales from the only pharmaceutical ophthalmologic laboratory, authorized to dispense them in Brazil (Opthalmos) were gathered. These data were correlated with geographic and seasonal distribution of fungal keratitis in Brazil between July 2002 and June 2008.ResultsA total of 26,087 antifungal eye drop units were sold, with a mean of 2.3 per patient. There was significant variation in antifungal sales during the year (p<0.01). A linear regression model displayed a significant association between reduced relative humidity and antifungal drug sales (R2 = 0.17,p<0.01).ConclusionsAntifungal eye drops sales suggest that there is a seasonal distribution of fungal keratitis. A possible interpretation is that the third quarter of the year (a period when the climate is drier), when agricultural activity is more intense in Brazil, suggests a correlation with a higher incidence of fungal keratitis. A similar model could be applied to other diseases, that are managed with unique, or few, and monitorable medications to predict epidemiological aspects.

Is dry eye an environmental disease?

“…Those indicators are also monitored by national and international health and/or environmental agencies. They are then applied in health analysis studies to correlate diseases with epidemiology, governmental policy directives, and economic studies (12,96,97) . This approach supports analysis of the health status of individuals or groups exposed to the above-indicated environmental risk factors.…”

Distribuição das ceratites infecciosas em hospital terciário no Brasil

“…Ibrahim et al estudaram a sazonalidade de ceratites fúngicas no Brasil através da venda de colírios antifúngicos. Os autores observaram relação do aumento de vendas de antifúngicos nos meses de menor umidade do ar (7) . A determinação da sazonalidade permitiria, por exemplo, desenvolvimento de ações preventivas contra essa doença, que pode ser extremamente debilitante.…”

Epidemiology of fungal keratitis treated with penetrating keratoplasty by means of histopathologic findings

“…Ibrahim et al studied the epidemiology of fungal keratitis by monitoring the sales of anti-fungal eyedrops in Brazil, and found an increase in sales in the third quarter, which somehow is in line with the findings of our study. The third quarter of the year is the harvest season for many crops such as corn, soybeans, sugarcane, coffee, rice and orange (39) , which leads us to think of a possible relation between the increase in the number of cases of fungal keratitis and the harvest season. Our findings are also in line with the hypothesis that in the tropics, during the dry season when agricultural activities are more frequent, there are more cases of corneal fungal infections (39,40) .…”

“…The third quarter of the year is the harvest season for many crops such as corn, soybeans, sugarcane, coffee, rice and orange (39) , which leads us to think of a possible relation between the increase in the number of cases of fungal keratitis and the harvest season. Our findings are also in line with the hypothesis that in the tropics, during the dry season when agricultural activities are more frequent, there are more cases of corneal fungal infections (39,40) . Finally, we must mention that the number of cases in the present study could have been underestimated at times, but we emphasize those with previous surgery, with subsequent surgery, or those developing to evisceration.…”