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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Understanding the spatial distribution of trichiasis and its association with trachomatous inflammation—follicular
AU - Flueckiger, Rebecca Mann
AU - Giorgi, Emanuele
AU - Cano, Jorge
AU - Abdala, Mariamo
AU - Amiel, Olga Nelson
AU - Baayenda, Gilbert
AU - Bakhtiari, Ana
AU - Batcho, Wilfrid
AU - Bennawi, Kamal Hashim
AU - Dejene, Michael
AU - Elshafie, Balgesa Elkheir
AU - Elvis, Aba Ange
AU - Francois, Missamou
AU - Goepogui, Andre
AU - Kalua, Khumbo
AU - Kebede, Biruck
AU - Kiflu, Genet
AU - Masika, Michael P.
AU - Massangaie, Marilia
AU - Mpyet, Caleb
AU - Ndjemba, Jean
AU - Ngondi, Jeremiah M.
AU - Olobio, Nicholas
AU - Turyaguma, Patrick
AU - Willis, Rebecca
AU - Yeo, Souleymane
AU - Solomon, Anthony W.
AU - Pullan, Rachel L.
PY - 2019/4/30
Y1 - 2019/4/30
N2 - BackgroundWhilst previous work has identified clustering of the active trachoma sign “trachomatous inflammation—follicular” (TF), there is limited understanding of the spatial structure of trachomatous trichiasis (TT), the rarer, end-stage, blinding form of disease. Here we use community-level TF prevalence, information on access to water and sanitation, and large-scale environmental and socio-economic indicators to model the spatial variation in community-level TT prevalence in Benin, Cote d’Ivoire, DRC, Guinea, Ethiopia, Malawi, Mozambique, Nigeria, Sudan and Uganda.MethodsWe fit binomial mixed models, with community-level random effects, separately for each country. In countries where spatial correlation was detected through a semi-variogram diagnostic check we then fitted a geostatistical model to the TT prevalence data including TF prevalence as an explanatory variable.ResultsThe estimated regression relationship between community-level TF and TT was significant in eight countries. We estimate that a 10% increase in community-level TF prevalence leads to an increase in the odds for TT ranging from 20 to 86% when accounting for additional covariates.ConclusionWe find evidence of an association between TF and TT in some parts of Africa. However, our results also suggest the presence of additional, country-specific, spatial risk factors which modulate the variation in TT risk.
AB - BackgroundWhilst previous work has identified clustering of the active trachoma sign “trachomatous inflammation—follicular” (TF), there is limited understanding of the spatial structure of trachomatous trichiasis (TT), the rarer, end-stage, blinding form of disease. Here we use community-level TF prevalence, information on access to water and sanitation, and large-scale environmental and socio-economic indicators to model the spatial variation in community-level TT prevalence in Benin, Cote d’Ivoire, DRC, Guinea, Ethiopia, Malawi, Mozambique, Nigeria, Sudan and Uganda.MethodsWe fit binomial mixed models, with community-level random effects, separately for each country. In countries where spatial correlation was detected through a semi-variogram diagnostic check we then fitted a geostatistical model to the TT prevalence data including TF prevalence as an explanatory variable.ResultsThe estimated regression relationship between community-level TF and TT was significant in eight countries. We estimate that a 10% increase in community-level TF prevalence leads to an increase in the odds for TT ranging from 20 to 86% when accounting for additional covariates.ConclusionWe find evidence of an association between TF and TT in some parts of Africa. However, our results also suggest the presence of additional, country-specific, spatial risk factors which modulate the variation in TT risk.
KW - Trachoma
KW - Trichiasis
KW - Blindness
KW - Visual impairment
KW - Neglected tropical disease
KW - Epidemiology
KW - Global trachoma mapping project
U2 - 10.1186/s12879-019-3935-1
DO - 10.1186/s12879-019-3935-1
M3 - Journal article
VL - 19
JO - BMC Infectious Diseases
JF - BMC Infectious Diseases
SN - 1471-2334
M1 - 364
ER -