Prevalence of Trachoma in Four Local Government Areas of Jigawa State, Nigeria.

PURPOSE: To determine the prevalence of trachoma and water and sanitation coverage in four local government areas (LGAs) of Jigawa State, Nigeria: Birnin Kudu, Buji, Dutse and Kiyawa. METHODOLOGY: A population-based cross-sectional survey was conducted in each LGA using Global Trachoma Mapping Project (GTMP) protocols. From each LGA, 25 villages were selected using probability-proportional-to-population size sampling; in each village, 25 households were selected using the random walk technique. All residents aged ≥1 year in selected households were examined by GTMP-certified graders for trachomatous inflammation - follicular (TF) and trichiasis, defined according to the WHO simplified trachoma grading scheme definitions. Water, sanitation and hygiene data were also collected through questioning and direct observation. RESULTS: In 2458 households of four LGAs, 10,669 residents were enumerated. A total of 9779 people (92% of residents) were examined, with slightly more females examined (5012; 51%) than men. In children aged 1-9 years, the age-adjusted prevalence of TF ranged from 5.1% (95% CI 2.5-9.0%) in Birnin Kudu to 12.8% (95% CI 7.6-19.4%) in Kiyawa, while the age- and gender-adjusted trichiasis prevalence in persons aged ≥15 years ranged from 1.9% (95% CI 1.4-2.5%) in Birnin Kudu to 3.1% (95% CI 2.2-4.0) in Dutse. Access to improved water sources was above 80% in all LGAs surveyed but access to improved sanitation facilities was low, ranging from 23% in Buji to 50% in Kiyawa. CONCLUSION: Trachoma is a public health problem in all four LGAs surveyed. The full SAFE strategy needs to be implemented to achieve trachoma elimination.

Prevalence and risk factors for diabetes and diabetic retinopathy: results from the Nigeria national blindness and visual impairment survey.

BACKGROUND: In Nigeria, urbanisation and increasing life expectancy are likely to increase the incidence of non-communicable diseases. As the epidemic of diabetes matures, visual loss from diabetic retinopathy (DR) will increase unless mechanisms for early detection and treatment improve, and health systems respond to the growing burden of non-communicable diseases. METHODS: A nationally-representative population-based sample of 13,591 participants aged ≥40 years selected by multistage-stratified-cluster-random-sampling with probability-proportional-to-size procedures were examined in 305 clusters in Nigeria between January 2005 to June 2007. All were asked about history of diabetes and underwent basic eye examination. Visual acuity (VA) was measured using logMAR E-chart. Participants with VA<6/12 and/or DR detected underwent detailed eye examination including dilated retinal examination and retinal photography. Systematic sampling of 1-in-7 gave a subsample (n=1759) examined in detail regardless of VA; and had random blood glucose (RBG) testing. Images were graded by Moorfields Eye Hospital Reading Centre. Participants were defined as having diabetes if they were previously diagnosed or RBG>11.1mmol/l or had DR. Data in the subsample were used to estimate the prevalence and to analyse risk factors for diabetes and DR using multivariable logistic regression. Additional information on the types of DR was obtained from participants not in the subsample. RESULTS: In the subsample, 164 participants were excluded due to missing data; and 1,595 analysed. 52/1,595 had diabetes, a prevalence of 3.3% (95%CI 2.5-4.3%); and 25/52(48%) did not know. Media opacity in 8/52 precluded retinal examination. 9/44(20.5%) had DR. Higher prevalence of diabetes was associated with urban residence (Odds ratio [OR]1.87) and overweight/obesity (OR3.02/4.43 respectively). Although not statistically significant, DR was associated with hypertension (OR3.49) and RBG>15.0mmol/L (OR8.10). Persons with diabetes had 3 times greater odds of blindness. Of 11,832 other participants in the study sample, 175(1.5%) had history of diabetes; 28 had DR. Types of DR (total=37) included 10.8% proliferative, 51.4% macular oedema. CONCLUSION: The age-adjusted prevalence of diabetes in Nigeria was 3.25% (95%CI 2.50-4.30) and over 10% of people with diabetes aged ≥40 years had sight-threatening-DR. These data will enable the development of better public health strategies for the control of diabetes and planning services for DR to prevent vision loss.