Purpose. To develop a mathematical model that describes the dynamics of transmission and progression of trachoma in hyperendemic areas. Methods. Trachoma, caused by repeated eye infections with Chlamydia, is the leading infectious cause of blindness worldwide, with an estimated 500 million affected and 7-9 million blind. The disease encompassses a broad range of symptoms from inflammation associated with infection (Active Trachoma), to later stages involving scarring of the eye lid, trichiasis and corneal opacities (Progression). Different trachoma control strategies have been indentified, including a health education approach to decrease transmission, mass or selective treatment with antibiotics, and surgical intervention for trichiasis, a potentially blinding sequela of the disease. An epidemiological model for the transmission and progression of trachoma has been developed. For the transmission component, the basic structure is SIS (susceptible-infective-susceptible) in which people repeatedly acquire and clear infection with a time scale of weeks; in addition, the basis structure distinguishes between presence of clinically active disease and presence of infection. The progression component characterizes the incidence of later stages of the disease with a time scale of years. Results. Comparisons between the predictions from the model and the observed effects of interventions in several hyperendemic communities in Tanzania are used to validate this approach. Conclusions. This modeling approach provides valuable information for the planning of optimal strategies for trachoma control in hyperendemic areas.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience