Environmental sanitation measures to reduce trachoma transmission

Trachoma is the commonest cause of preventable vision loss and is common in poor communities. Repeated bouts of conjunctivitis caused by chlamydia infection lead to scarring and turning in of the eyelid. The lashes rub the cornea causing opacification and blindness. Environmental sanitation is a package of measures aimed at eliminating factors that encourage proliferation of flies and the spread of the disease. Some of these interventions include provision of water and latrines as well insecticide spray to control flies. Four studies involving 10,356 participants of all ages and both sexes were included in this review. The trials were conducted in The Gambia, Mali and Tanzania. Two studies looked at insecticide spray, one looked at insecticide spray and provision of latrines and another study looked at health education. Prevalence of active trachoma and fly count measures were two of the main outcomes assessed. Two studies conducted in the same area found insecticide spray effective in reducing active trachoma but one study in a different setting found the spray ineffective. A separate study found health education on personal and environmental hygiene to be effective in reducing active trachoma. However, more research is needed.