The epidemiology of trachoma in rural Kenya. Variation in prevalence with lifestyle and environment. Study Survey Group.
OBJECTIVE
Ocular examination surveys were carried out in Kenya by the International Eye Foundation as a component of the Kenya Rural Blindness Prevention Project to determine the national prevalence of blindness and ocular morbidity and major causes. A goal of the surveys was to determine the overall geographic distribution and severity of trachoma throughout Kenya.


METHODS
Using a random cluster household sampling technique, 13,803 people of all ages and of diverse cultural and ethnic backgrounds were identified in eight regions of Kenya. A detailed examination for active and inactive trachoma was carried out on each person surveyed as part of the general ocular examination.


RESULTS
The prevalence rate of visual loss (< 20/60) due to trachoma in the better eye was 7.2/1000. Active trachoma was present in 19% of all persons examined, and 50% of all those with trachoma were found to have moderate to severe inflammation. Prevalence varied according to survey region from less than 1% in four regions where agriculture is the economic base, to 57% and 63% in two arid pastoral regions. Trachoma prevalence varied from 28% in children younger than 3 years of age to 11% in persons older than 60 years of age. Potentially blinding eyelid deformities secondary to chronic trachoma occurred in 5.0% of the rural population, and 1.2% of the rural population displayed associated corneal scarring. Lid scarring, corneal scarring, and lid deformities were greater in prevalence among females of all age groups when compared with males.


CONCLUSIONS
Trachoma prevalence in Kenya varies widely from region to region. High prevalence is associated with high climatic aridity, and lower prevalence is associated with areas of greater rainfall, sustainable agriculture, and a higher general standard of living. Within high-risk regions, there are wide variations in age-specific prevalence and severity of the disease. Potentially blinding sequelae of trachoma are more prevalent in females than in males.
Schwab
L
L
International Eye Foundation, Bethesda, MD 20814.
Whitfield
R
R
Ross-Degnan
D
D
Steinkuller
P
P
Swartwood
J
J
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001766:Blindness / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D004777:Environment; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007630:Kenya / Q000453:epidemiology; D008019:Life Style / Q000208:ethnology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014141:Trachoma / Q000150:complications / Q000453:epidemiology* / Q000208:ethnology