Floristic Diversity as an Indicator in Low and High Endemic Buruli Ulcer Areas in Côte d'Ivoire.

Mycobacterium ulcerans is an environmental bacterium responsible for Buruli ulcer. This disease has a high frequency index in humid tropical regions, with a high incidence in Sub-Saharan Africa. The ecology and mode of transmission of this disease is not well established. Based on dilution effect hypothesis, acting as lowering disease transmission due to greater biodiversity, floristic inventory was carried out in the Health Districts of Daloa and Bouaké in Côte d'Ivoire. In each district, high and low endemic sites were investigated. A total of 169 plant species were inventoried for both low and high endemicity of Buruli ulcer sites in the districts. The Indval index revealed that 13 plant species were good indicators for Buruli ulcer highly endemic areas. The plants which correlate with high endemicity area were Leersia hexandra, Panicum laxum, Mimosa pudica, Paspalum distichum, Persicaria senegalensis, Calopogonium mucunoides, Echinochloa colona, Ipomoea sagittata, and Eichhornia crassipes. For low endemic sites, a strong relationship was recorded for 37 plants. The indices revealed low similarity between high and low endemicity sites. Low endemicity sites expressed the highest plant species diversity. These results suggest the hypothesis that floristic richness is more important in sites of low endemicity than in those of high endemicity. Moreover, we observed a co-occurrence of some plant species and Buruli ulcer endemicity. This finding may lead to the fact that it is important to care about the biodiversity to prevent outbreak of Buruli ulcer cases. Supplementary Information: The online version contains supplementary material available at 10.1007/s41742-023-00520-2.

Impact of climate variability on the transmission risk of malaria in northern Côte d'Ivoire.

Since the 1970s, the northern part of Côte d'Ivoire has experienced considerable fluctuation in its meteorology including a general decrease of rainfall and increase of temperature from 1970 to 2000, a slight increase of rainfall since 2000, a severe drought in 2004-2005 and flooding in 2006-2007. Such changing climate patterns might affect the transmission of malaria. The purpose of this study was to analyze climate and environmental parameters associated with malaria transmission in Korhogo, a city in northern Côte d'Ivoire. All data were collected over a 10-year period (2004-2013). Rainfall, temperature and Normalized Difference Vegetation Index (NDVI) were the climate and environmental variables considered. Association between these variables and clinical malaria data was determined, using negative binomial regression models. From 2004 to 2013, there was an increase in the annual average precipitation (1100.3-1376.5 mm) and the average temperature (27.2°C-27.5°C). The NDVI decreased from 0.42 to 0.40. We observed a strong seasonality in these climatic variables, which resembled the seasonality in clinical malaria. An incremental increase of 10 mm of monthly precipitation was, on average, associated with a 1% (95% Confidence interval (CI): 0.7 to 1.2%) and a 1.2% (95% CI: 0.9 to 1.5%) increase in the number of clinical malaria episodes one and two months later respectively. A 1°C increase in average monthly temperature was, on average, associated with a decline of a 3.5% (95% CI: 0.1 to 6.7%) in clinical malaria episodes. A 0.1 unit increase in monthly NDVI was associated with a 7.3% (95% CI: 0.8 to 14.1%) increase in the monthly malaria count. There was a similar increase for the preceding-month lag (6.7% (95% CI: 2.3% to 11.2%)). The study results can be used to establish a malaria early warning system in Korhogo to prepare for outbreaks of malaria, which would increase community resilience no matter the magnitude and pattern of climate change.

[Hepatitis B knowledge among secondary school students in Côte d'Ivoire]. / Connaissance de l'hépatite virale B par les élèves des écoles secondaires en Côte d'Ivoire.

AIM: The purpose of this study was to assess hepatitis B knowledge among secondary school students' in Côte d'Ivoire in order to promote the inclusion of hepatitis B education in school curricula. MATERIAL AND METHODS: a single cross-sectional survey involving six schools (7,376 students) was conducted. Data were collected using a self-administered questionnaire. RESULTS: All students present on the day of the survey agreed to participate in the study (100%, n = 3,352). The mean age of the participants was 17.9 years (10-26 years), with a male-to-female sex ratio of 1.68. Among them, 2,552 (76.6%) had heard of the HVB. School was the main source of information (12%), after the mass media (62%). The causative agent of the disease was known by 74.1% of students (n = 2,484), sexual transmission by 39.3% (n = 1316), and blood-borne transmission by 57.2% (n = 1919). Respectively 29%, 40% and 41% of the students were aware that acupuncture, body piercing and tattooing are high-risk practices. Only 35.7% of the students knew that there was an effective vaccine. The factors associated with hepatitis B knowledge were: being aged 16 to 20 years (OR = 1.73 [95% CI 1.198 to 2.49]), living in a permanent house or apartment (OR = 1.58 [95% CI 1.234 to 2.02]) or in a house or apartment with no more than 2 persons per room (OR = 1.41 [95% CI 1.15 to 1.74]), being in terminale (final year of high school) (OR = 2.54 [2.01 to 3, 20IC95%]), and having two working parents (OR =1.54 [95% CI 1.25 to 1.88]). CONCLUSION: The students' knowledge of the hepatitis B virus was found to be inadequate and superficial. Early awareness programs provided as part of the official curriculum and measures to improve the social conditions of students should help to improve knowledge in this area.

In vivo anthelmintic activity of Anogeissus leiocarpus Guill & Perr (Combretaceae) against nematodes in naturally infected sheep.

The identification of new anthelmintic drugs becomes a priority because of the availability of a handful of drugs, cost of treatments, and recent emergence of drug resistance. Medicinal plants are a good source of bioactive compounds for development of drugs. In this study, in vivo efficacy of Anogeissus leiocarpus was assessed in sheep naturally infected with gastrointestinal nematodes. Fecal examination, serological analyses, and necropsy were carried out to determine the egg and worm-burden reduction. The administration of ethanolic extract (single oral dose of 80 mg/kg) of A. leiocarpus induced a moderate fecal egg reduction (81 %) and adult worm-burden reduction (87 %) against Haemonchus contortus and Trichostrongylus colubriformis (82 %). The plant exhibited high efficacy against adult Strongyloïdes papillosus (100 %), Gaigeria pachyscelis (90 %), Cooperia curticei (100 %), and Oesophagostomum columbianum (95 %) but low efficacy against Trichostrongylus axei (67 %) and Trichuris globulosa (79 %). All these helminthes were sensitive to fenbendazole, except O. columbianum which showed a decrease susceptibility (17 %). The plant extract also improved certain biological parameters by increasing bodyweight from 0.7 ± 2.9 to 3.3 ± 1.9 % and improving hematocrit of 6.9 ± 1.6 % 3-week posttreatment. It emerges from the results that the plant possesses significant effectiveness on diarrhea; all treated animals gave normal feces. This study has shown that A. leiocarpus could find an application in the control of multiparasitism in small ruminants.