Update on the current status of onchocerciasis in Cote d’Ivoire following 40 years of intervention: Progress and challenges

Background Onchocerciasis control in Côte d’Ivoire started with aerial insecticide spraying in 1974 and continued with community directed treatment with ivermectin (CDTi) from 1992 to the present. Onchocerciasis and lymphatic filariasis (LF) are co-endemic in 46 of the 81 health districts in the country. Fourteen and 12 districts are endemic for only LF or onchocerciasis, respectively. This paper aims to review the impact of past interventions on onchocerciasis in Côte d’Ivoire between 1975 and 2013, and review plans for disease elimination. Methods We reviewed microfilaria (MF, skin snip) prevalence and community microfilarial load (CMFL) data from published reports from 53 health districts during two major epidemiological assessment periods. Data from 1975 through 1991 provided information on the impact of vector control, and data from 1992 through 2016 provided information on the impact of CDTi. Results Weekly aerial insecticide spraying in 8 endemic districts between 1975 and 1991 reduced the overall MF prevalence by 68.1% from 43.5% to 13.9%. The CMFL also decreased in 7 out of 8 surveyed communities by 95.2% from 9.24 MF/snip to 0.44 MF/snip. Ivermectin distribution started in 1992. The coverage targets for control (65% of the total population) was reached in most endemic districts, and some areas achieved 80% coverage. Two sets of surveys were conducted to assess the impact of CDTi. Results from the first repeat surveys showed a significant decrease in overall MF prevalence (by 75.7%, from 41.6% to 10.1%). The second follow-up evaluation showed further improvement in most endemic districts and also documented major reductions in CMFL compared to baseline. Conclusions Extensive data collected over many years document the very significant impact of interventions conducted by the National Onchocerciasis and other Eyes Diseases Control Programme during challenging times with periods of civil unrest. The Health Ministry has now integrated efforts to control neglected tropical diseases and adopted the goal of onchocerciasis elimination

Monitoring of anthropogenic effects on forest ecosystems within the municipality of Valli`eres in the Republic of Haiti from 1984 to 2019

The forest resources within the municipality of Valli`eres in the Republic of Haiti are subject to ever-increasing anthropogenic pressures, leading to a reduction in their area and the degradation of their ecosystem services. This study quantified the spatial pattern changes of forest ecosystems within the municipality of Valli`eres from 1984 to 2019 using a cartographic approach coupled with landscape metrics. The evolving trend in the landscape within the municipality of Valli`eres and its sections reveals that in 35 years the area of forests land has diminished through the fragmentation of the large initial patches, as opposed to the progressive dynamics of agricultural and bare land, mainly under strain from the creation and merging of the patches. The underlying causes of the observed landscape dynamics are demographic pressure coupled with the lack of an appropriate program for the preservation of forest resources and improvement of the standard of living conditions of the local population. Our results justify the implementation of strategies to preserve the rare patches of the forests that remain, taking into account the local socio-economic context.Peer reviewe

Mapping and quantification of the loss of forest cover in the national parks of the South of the Republic of Haiti from 1985 to 2018: role of local agricultural activities

In Haiti, national parks were created to preserve the rare forests that are constantly threatened by agriculture and livestock. However, scientific studies on the landscape dynamics of forest ecosystems in Haiti’s parks have received little attention. The objective of this study is to map and quantify the loss of forest cover in the natural national parks of Forêt des Pins (PNN-FP2), La-visite (PNN-LV) and Macaya (PNN-M) from 1985 to 2018. A diachronic analysis, thanks to the supervised classification of Landsat images based on landscape ecology analysis tools, was carried out. The results show a landscape dynamic materialized by forest cover losses of 56%, 36% and 46% respectively within the PNN-FP2, PNN-LV and PNN-M between 1985 and 2018, through the dissection and fragmentation of stains as opposed to the progressive dynamics of agricultural areas and bare soil underpinned by the creation and aggregation of stains. The annual rates of deforestation, significant between 1998 / 1999-2017 / 2018, varied between -0.09% and -2.72% depending on the park. Given that the landscapes of these three national parks studied are very dynamic, it is urgent to adopt a policy of their conservation supported by local socio-economic development measures

Glob Health Action

Adolescents living with HIV are sexually active and engaged in risky sexual behaviors. Knowledge on how and to what extent adolescents in HIV care are affected by pregnancy is needed so as to adopt better preventive services. We estimated 4-year pregnancy incidence and correlates among HIV-infected female adolescents in HIV care in urban Côte d'Ivoire. We conducted retrospective analysis of a pediatric prospective cohort of the International epidemiological Databases to Evaluate AIDS (IeDEA) West Africa Collaboration. Female patients with confirmed HIV infection aged 10-19 years, having at least one clinical visit in 2009 to health facilities participating in the pediatric IeDEA West African cohort in Abidjan, Côte d'Ivoire, were included. Data on incident pregnancies were obtained through medical records and interviews with health professionals. Pregnancy incidence rate was estimated per 100 person-years (PY). Poisson regression models were used to identify factors associated with the first pregnancy and provided incidence rate ratios (IRR) with 95% confidence intervals (CI). In 2009, 266 female adolescents were included, with a median age of 12.8 years (interquartile range, IQR: 10.0-15.0), CD4 cell counts of 506 cells/mm(3) (IQR: 302-737), and 80% on antiretroviral treatment. At the 48th month, 17 new pregnancies were reported after 938 PY of follow-up: 13 girls had one pregnancy while 2 had two pregnancies. Overall incidence rate of pregnancy was 1.8/100 PY (95% CI: 1.1-2.9). High incidence was observed among those aged 15-19 years: 3.6/100 PY (95% CI: 2.2-5.9). Role of maternal death in the risk of pregnancy was at the limit of statistical significance (adjusted IRR: 3.1, 95% CI: 0.9-11.0; ref. non-maternal orphans). Incidence of pregnancy among HIV-infected adolescents in care aged 15-19 years reached a level observed in adult cohorts in Sub-Saharan Africa. Health personnel in pediatric care have to intensify their efforts to provide more realistic and age-adapted reproductive health services to meet the needs of adolescent patients already confronting issues of sexuality. Vulnerability of maternal orphans merits further investigation

Sanitation and water supply coverage thresholds associated with active trachoma: Modeling cross-sectional data from 13 countries.

BACKGROUND: Facial cleanliness and sanitation are postulated to reduce trachoma transmission, but there are no previous data on community-level herd protection thresholds. We characterize associations between active trachoma, access to improved sanitation facilities, and access to improved water sources for the purpose of face washing, with the aim of estimating community-level or herd protection thresholds. METHODS AND FINDINGS: We used cluster-sampled Global Trachoma Mapping Project data on 884,850 children aged 1-9 years from 354,990 households in 13 countries. We employed multivariable mixed-effects modified Poisson regression models to assess the relationships between water and sanitation coverage and trachomatous inflammation-follicular (TF). We observed lower TF prevalence among those with household-level access to improved sanitation (prevalence ratio, PR = 0.87; 95%CI: 0.83-0.91), and household-level access to an improved washing water source in the residence/yard (PR = 0.81; 95%CI: 0.75-0.88). Controlling for household-level water and latrine access, we found evidence of community-level protection against TF for children living in communities with high sanitation coverage (PR80-90% = 0.87; 95%CI: 0.73-1.02; PR90-100% = 0.76; 95%CI: 0.67-0.85). Community sanitation coverage levels greater than 80% were associated with herd protection against TF (PR = 0.77; 95%CI: 0.62-0.97)-that is, lower TF in individuals whose households lacked individual sanitation but who lived in communities with high sanitation coverage. For community-level water coverage, there was no apparent threshold, although we observed lower TF among several of the higher deciles of community-level water coverage. CONCLUSIONS: Our study provides insights into the community water and sanitation coverage levels that might be required to best control trachoma. Our results suggest access to adequate water and sanitation can be important components in working towards the 2020 target of eliminating trachoma as a public health problem

Landscape dynamics of the Forêt des Pins National Natural Park in Haiti (1973- 2018)

In Haiti, forest cover is in constant decline and does not exceed 3.5% of the national territory. Parks have been created to preserve the rare forests, including Unit 2 of the Pine Forest National Natural Park (PNN-FP2). However, the meager forest resources of this park are subject to various anthropogenic pressures (agriculture, timber exploitation, urbanization, etc.) leading to the decline of their area in the landscape. This study evaluated the spatio-temporal dynamics of the anthropization of forest ecosystems in PNN-FP2 from four Landsat images dating from 1973, 1986, 1999 and 2018. The cartographic approach combined with the analysis tools of landscape ecology revealed that the natural forest cover has experienced, in 45 years (from 1973 to 2018), a regressive dynamic materialized by a loss of 59.63% of its coverage to the benefit of anthropogenic classes (Fields and fallows, Degraded vegetation and Bare land) The regression of forest cover is underpinned by the dissection and fragmentation of its spots as opposed to the creation of the anthropogenic class spots. Our results justify the urgent need to develop an integrated, adequate and participatory management policy in order to sustainably preserve the forests of PNN-FP2

Land Cover Dynamics along the Urban–Rural Gradient of the Port-au-Prince Agglomeration (Republic of Haiti) from 1986 to 2021

The landscape of the Port-au-Prince agglomeration in the Republic of Haiti has undergone profound changes linked to (peri-)urban expansion supported by rapid demographic growth. We quantify the land cover dynamics along the urban–rural gradient of the Port-au-Prince agglomeration using Landsat images from 1986, 1998–1999, 2010, and 2021 coupled with geographic information systems and landscape ecology analysis tools. The results show that over 35 years the acreage of the urban zone increased seven-fold while that of the peri-urban area increased five-fold, to the detriment of the rural zone, which was reduced by 14%. The dynamics of the landscape composition along the urban–rural gradient are characterized by a rapid progression of built-up and bare land in urban and peri-urban zones and by fields in the rural zone, in contrast to the more accentuated regression of vegetation in the peri-urban zone. The landscape of the study area has undergone significant changes due to the high demand for housing resulting from rapid population growth, in the context of a lack of territorial development planning by public authorities. This impacts the sustainability of socio-economic and ecological processes in an area where populations are highly dependent on plant resources. Our results underline the necessity to orient territorial development planning in urban, peri-urban and rural zones through an integrated and participatory approach

Progress towards onchocerciasis elimination in Côte d'Ivoire: A geospatial modelling study.

BackgroundCôte d'Ivoire has had 45 years of intervention for onchocerciasis by vector control (from 1975 to 1991), ivermectin mass drug administration (MDA) (from 1992 to 1994) and community directed treatment with ivermectin (CDTi) from 1995 to the present. We modeled onchocerciasis endemicity during two time periods that correspond to the scale up of vector control and ivermectin distribution, respectively. This analysis illustrates progress towards elimination during these periods, and it has identified potential hotspots areas that are at risk for ongoing transmission.Methods and findingsThe analysis used Ministry of Health skin snip microfilaria (MF) prevalence and intensity data collected between 1975 and 2016. Socio-demographic and environmental factors were incorporated into a predictive, machine learning algorithm to create continuous maps of onchocerciasis endemicity. Overall predicted mean MF prevalence decreased from 51.8% circa 1991 to 3.9% circa 2016. The model predicted infection foci with higher prevalence in the southern region of the country. Predicted mean community MF load (CMFL) decreased from 10.1MF/snip circa 1991 to 0.1MF/snip circa 2016. Again, the model predicts foci with higher Mf densities in the southern region. For assessing model performance, the root mean squared error and R2 values were 1.14 and 0.62 respectively for a model trained with data collected prior to 1991, and 1.28 and 0.57 for the model trained with infection survey data collected later, after the introduction of ivermectin. Finally, our models show that proximity to permanent inland bodies of water and altitude were the most informative variables that correlated with onchocerciasis endemicity.Conclusion/significanceThis study further documents the significant reduction of onchocerciasis infection following widespread use of ivermectin for onchocerciasis control in Côte d'Ivoire. Maps produced predict areas at risk for ongoing infection and transmission. Onchocerciasis might be eliminated in Côte d'Ivoire in the future with a combination of sustained CDTi with high coverage, active surveillance, and close monitoring for persistent infection in previously hyper-endemic areas

Progress towards onchocerciasis elimination in Côte d\u27Ivoire: A geospatial modelling study

BACKGROUND: Côte d\u27Ivoire has had 45 years of intervention for onchocerciasis by vector control (from 1975 to 1991), ivermectin mass drug administration (MDA) (from 1992 to 1994) and community directed treatment with ivermectin (CDTi) from 1995 to the present. We modeled onchocerciasis endemicity during two time periods that correspond to the scale up of vector control and ivermectin distribution, respectively. This analysis illustrates progress towards elimination during these periods, and it has identified potential hotspots areas that are at risk for ongoing transmission. METHODS AND FINDINGS: The analysis used Ministry of Health skin snip microfilaria (MF) prevalence and intensity data collected between 1975 and 2016. Socio-demographic and environmental factors were incorporated into a predictive, machine learning algorithm to create continuous maps of onchocerciasis endemicity. Overall predicted mean MF prevalence decreased from 51.8% circa 1991 to 3.9% circa 2016. The model predicted infection foci with higher prevalence in the southern region of the country. Predicted mean community MF load (CMFL) decreased from 10.1MF/snip circa 1991 to 0.1MF/snip circa 2016. Again, the model predicts foci with higher Mf densities in the southern region. For assessing model performance, the root mean squared error and R2 values were 1.14 and 0.62 respectively for a model trained with data collected prior to 1991, and 1.28 and 0.57 for the model trained with infection survey data collected later, after the introduction of ivermectin. Finally, our models show that proximity to permanent inland bodies of water and altitude were the most informative variables that correlated with onchocerciasis endemicity. CONCLUSION/SIGNIFICANCE: This study further documents the significant reduction of onchocerciasis infection following widespread use of ivermectin for onchocerciasis control in Côte d\u27Ivoire. Maps produced predict areas at risk for ongoing infection and transmission. Onchocerciasis might be eliminated in Côte d\u27Ivoire in the future with a combination of sustained CDTi with high coverage, active surveillance, and close monitoring for persistent infection in previously hyper-endemic areas

Growth in the first 5 years after antiretroviral therapy initiation among HIV‐infected children in the IeDEA West African Pediatric Cohort

To describe growth evolution and its correlates in the first 5 years of antiretroviral therapy (ART) initiation among HIV-infected children followed up in West Africa. All HIV-infected children younger than 10 years followed in the IeDEA pWADA cohort while initiating ART, with at least one anthropometric measurement within the first 5 years of treatment were included in the study. Growth was described according to the WHO child growth standards, using Weight-for-age Z-score (WAZ), Height-for-age Z-score (HAZ) and Weight-for-Height/BMI-for-age Z-score (WHZ/BAZ). Growth evolution and its correlates, measured at ART initiation, were modelled in individual linear mixed models for each anthropometric indicator, with a spline term added at the 12-, 24- and 9-month time point for WAZ, HAZ and WHZ/BAZ, respectively. Among the 4156 children selected (45% girls, median age at ART initiation 3.9 years [IQR interquartile range 1.9-6.6], and overall 68% malnourished at ART initiation), important gains were observed in the first 12, 24 and 9 months on ART for WAZ, HAZ and WHZ/BAZ, respectively. Correlates at ART initiation of a better growth evolution overtime were early age (<2 years of age), severe immunodeficiency for age, and severity of malnutrition. Growth evolution is particularly strong within the first 2 years on ART but slows down after this period. Weight and height gains help to recover from pre-ART growth deficiency but are insufficient for the most severely malnourished. The first year on ART could be the best period for nutritional interventions to optimize growth among HIV-infected children in the long-term. Décrire l’évolution de la croissance et ses corrélats au cours des cinq premières années d'initiation du traitement antirétroviral (ART) chez les enfants infectés par le VIH, suivis en Afrique de l'Ouest. MÉTHODES: Tous les enfants infectés par le VIH âgés de moins de 10 ans suivis dans la cohorte IeDEA pWADA au début de l’ART, avec au moins une mesure anthropométrique au cours des cinq premières années de traitement, ont été inclus dans l’étude. La croissance a été décrite selon les normes de croissance de l'enfant de l’OMS, en utilisant le Z-score Poids pour l’âge (WAZ), le Z-score Taille pour l’âge (HAZ) et le Z-score Poids-pour-Taille/IMC pour l’âge (WHZ/BAZ). L’évolution de la croissance et ses corrélats, mesurés au début de l’ART, ont été modélisés dans des modèles mixtes linéaires individuels pour chaque indicateur anthropométrique, avec un terme spline ajouté aux points 12, 24 et 9 mois pour WAZ, HAZ et WHZ/BAZ respectivement. RÉSULTATS: Parmi les 4.156 enfants sélectionnés (45% de filles, âge médian au début l’ART 3,9 ans [intervalle interquartile IQR de 1,9 à 6,6] et au total 68% de malnutrition au début de l’ART), des gains importants ont été observés dans les 12, 24 et 9 premiers mois sous ART pour WAZ, HAZ et WHZ/BAZ respectivement. Les corrélats au début de l’ART pour une meilleure évolution de la croissance au cours du temps étaient: l’âge précoce (<2 ans), un déficit immunitaire sévère pour l’âge et la sévérité de la malnutrition. L’évolution de la croissance est particulièrement forte au cours des deux premières années sous ART, mais ralentit après cette période. Les gains de poids et de taille aident à récupérer du retard de croissance pré-ART mais sont insuffisants pour les plus sévèrement malnutris. La première année sous ART pourrait être la meilleure période pour les interventions nutritionnelles visant à optimiser la croissance à long terme des enfants infectés par le VIH.Objectif: Décrire l’évolution de la croissance et ses corrélats au cours des cinq premières années d'initiation du traitement antirétroviral (ART) chez les enfants infectés par le VIH, suivis en Afrique de l'Ouest. Méthodes: Tous les enfants infectés par le VIH âgés de moins de 10 ans suivis dans la cohorte IeDEA pWADA au début de l’ART, avec au moins une mesure anthropométrique au cours des cinq premières années de traitement, ont été inclus dans l’étude. La croissance a été décrite selon les normes de croissance de l'enfant de l’OMS, en utilisant le Z-score Poids pour l’âge (WAZ), le Z-score Taille pour l’âge (HAZ) et le Z-score Poids-pour-Taille/IMC pour l’âge (WHZ/BAZ). L’évolution de la croissance et ses corrélats, mesurés au début de l’ART, ont été modélisés dans des modèles mixtes linéaires individuels pour chaque indicateur anthropométrique, avec un terme spline ajouté aux points 12, 24 et 9 mois pour WAZ, HAZ et WHZ/BAZ respectivement. Résultats: Parmi les 4.156 enfants sélectionnés (45% de filles, âge médian au début l’ART 3,9 ans [intervalle interquartile IQR de 1,9 à 6,6] et au total 68% de malnutrition au début de l’ART), des gains importants ont été observés dans les 12, 24 et 9 premiers mois sous ART pour WAZ, HAZ et WHZ/BAZ respectivement. Les corrélats au début de l’ART pour une meilleure évolution de la croissance au cours du temps étaient: l’âge précoce (<2 ans), un déficit immunitaire sévère pour l’âge et la sévérité de la malnutrition. Conclusions: L’évolution de la croissance est particulièrement forte au cours des deux premières années sous ART, mais ralentit après cette période. Les gains de poids et de taille aident à récupérer du retard de croissance pré-ART mais sont insuffisants pour les plus sévèrement malnutris. La première année sous ART pourrait être la meilleure période pour les interventions nutritionnelles visant à optimiser la croissance à long terme des enfants infectés par le VIH