Mapping Trachoma in Kaduna State, Nigeria: Results of 23 Local Government Area-Level, Population-Based Prevalence Surveys

Abstract

Introduction: To prepare for global elimination of trachoma by 2020, the World Health Organization (WHO) recommends mapping of trachoma at district-level to enable planning of elimination activities in affected populations. The aim of our study was to provide data on trachoma for each local government area (LGA) of Kaduna State, Nigeria, as such data were previously unavailable. Method: As part of the Global Trachoma Mapping Project (GTMP), a population-based cross-sectional trachoma survey was conducted in each of the 23 LGAs of Kaduna State, between May and June 2013. The protocols of the GTMP were used. Results: The prevalence of trachomatous inflammation – follicular (TF) in children aged 1–9 years was between 0.03% and 8% across the LGAs, with only one LGA (Igabi) having a TF prevalence ≥5%. The LGA-level prevalences of trichiasis in persons aged 15 years and older were between 0.00% and 0.78%. Eleven LGAs had trichiasis prevalences of 0.2% and over in adults; a threshold equivalent to 1 case per 1000 total population. The LGA-level proportion of households with access to improved water sources ranged from 9% to 96%, while household access to latrines ranged from 5% to 99%. Conclusion: Kaduna State has generally hypoendemic trachoma, but a few trichiasis surgeries are still required to attain the WHO elimination targets. Better access to improved water and sanitation is needed.

Impact Survey Results after SAFE Strategy Implementation in 15 Local Government Areas of Kebbi, Sokoto and Zamfara States, Nigeria

“…We controlled for age and gender of those examined, and the total number of people examined per cluster, using algorithms applied across all constituent projects of the GTMP. [18][19][20][21][22][23] For TF, the proportion of children aged 1-9 years who had that sign in each cluster was adjusted for age in 1-year age bands. For trichiasis and TT, the proportion of adults aged ≥15 years who had that sign in each cluster was adjusted for age and gender in 5-year age bands.…”

“…From the selected administrative unit, 25 households were selected using the random walk method. [18][19][20][21][22][23] Based on there being a mean of two children aged 1-9 years per household, this was expected to allow recruitment from a resident population of 1250 1-9-yearolds in each LGA, which would allow for partial nonresponse. In Arewa, we subdivided the LGA into four subunits and selected 25 clusters from each, in order to investigate how much additional information sub-district-level surveys would provide in this environment at the impact survey stage; thus a total of 100 clusters were selected in Arewa.…”

Prevalence of and risk factors for trachoma in Kwara state, Nigeria: Results of eight population-based surveys from the Global Trachoma Mapping Project

“…That is good news for Kwara and its people. Kogi State, which borders Kwara to the east, also enjoys prevalence of trachoma below those felt to represent a public health problem, 38 reinforcing the impression that deployment of the SAFE strategy for trachoma elimination may be required in the northern half of Nigeria, 24,25,[39][40][41][42][43][44][45][46] but not the southern half. Further trachoma mapping in Kwara State is not presently indicated.…”

Prevalence of Trachoma in Kogi State, Nigeria: Results of four Local Government Area-Level Surveys from the Global Trachoma Mapping Project

“…This sample size would be sufficient to allow an expected 10% prevalence of trachomatous inflammation-follicular (TF) to be estimated with absolute precision of 3%, assuming a design effect of 2.65 and inflating by a factor of 1.2 to adjust for non-response. [20][21][22][23][24][25][26]29 Team training…”

“…Nigeria has a high trachoma burden. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] Kogi State, located in central Nigeria, has a population of 3.3 million people 27 and had not previously been formally surveyed for the disease. To its north, Kogi borders currently or previously trachoma-endemic districts (Local Government Areas, LGAs) of Nasarawa 16 and Niger 24 States.…”