Prevalence of Trachoma in Niger State, North Central Nigeria: Results of 25 Population-Based Prevalence Surveys Carried Out with the Global Trachoma Mapping Project

Abstract

Purpose: To determine the prevalence of trachoma in each of the 25 local government areas (LGAs) of Niger State, Nigeria. Methods: A population-based cross-sectional survey was conducted in each Niger State LGA between March and April 2014, as part of the Global Trachoma Mapping Project (GTMP). GTMP protocols were used in planning and conduct of the surveys. Using probability proportional to size, 25 clusters were selected; in each of these clusters, 25 households were enrolled for the survey. All residents aged 1 year and older were examined by GTMP-certified graders for trachomatous inflammation – follicular (TF) and trichiasis using the World Health Organization simplified grading scheme. Additionally, we collected data on household water and sanitation facilities. Results: Only one LGA (Kontagora) had TF prevalence in 1–9-year-olds above 10%; one other LGA (Rafi) had TF prevalence between 5.0 and 9.9%. Six LGAs need trichiasis surgical services provided to achieve a prevalence of <1 case of trichiasis per 1000 total population. The proportion of households with access to improved water sources ranged from 23 to 100%, while household-level access to improved latrines ranged from 8 to 100% across the LGAs. Conclusion: The prevalence of trachoma is relatively low in most of Niger State. There is a need for community-based trichiasis surgical services in a small number of LGAs. The trachoma elimination program could engage water and sanitation agencies to augment access to improved water and sanitation facilities, for human rights reasons. Kontagora and Rafi need community-based interventions to reduce the prevalence of active trachoma.

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.…”

“…LGAs required 3 years of azithromycin mass drug administration (MDA, TF prevalence 10-29.9%) and 7 other LGAs required 5 years of azithromycin MDA (TF prevalence ≥30.0%), together with appropriate F & E interventions. The remaining 22 LGAs had TF prevalence estimates <10% and (according to thencurrent WHO guidance 12 ) did not qualify for district-wide antibiotic MDA. Based on the prevalence of trichiasis in persons aged ≥15 years, 40 LGAs surveyed required community-based trichiasis surgery to reach the trichiasis elimination threshold.…”

“…Based on the prevalence of trichiasis in persons aged ≥15 years, 40 LGAs surveyed required community-based trichiasis surgery to reach the trichiasis elimination threshold. The decision was made to implement various aspects of the SAFE strategy in 49 LGAs found to have trachoma of public health significance (27 LGAs with TF prevalence ≥10% and 40 LGAs with trichiasis prevalence ≥0.2%, of which 22 LGAs required public-health-level trichiasis interventions [S], 9…”

“…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.…”