Prévalences des Parasites Intestinaux Humains Chez les Patients du Service de Parasitologie de l’INRSP Bamako de 2010 à 2015

Introduction: L’invasion de l’appareil digestif humain par les parasites est le motif de consultation de plusieurs patients à l’Institut National de Recherche en Santé Publique (INRSP). Objectifs : Il s’agissait de déterminer la prévalence des parasites intestinaux humains chez les patients reçus au laboratoire de parasitologie de l’INRSP pendant la période de 2010 à 2015. Ce qui permettra de mesurer l’impact de l’amélioration de la situation sanitaire sur la transmission des parasites intestinaux au sein de la population humaine de la ville de Bamako. Méthodologie : C’était une étude rétrospective basée sur les résultats portés dans les registres de laboratoire. Résultats : Au total, 1833 individus sur 3815 patients étaient positifs aux infections intestinales parasitaires. Une prévalence de 44% a été obtenue chez les sujets féminins contre 42,2% chez les patients masculins. Les tranches d’âges de 1 à 10 ans et ceux de 11 à 20 ans étaient plus infectés avec 46,5%. L’ethnie Bambara avait le plus élevé taux d’infection (46%) et les Tamasheks avaient le plus bas taux (30%), alors que les élèves et étudiants avec 46,5% étaient la couche socio-professionnelle la plus infectée. Les douleurs abdominales étaient les plus fréquents signes cliniques. Entamoeba histolytica, 72% et Giardia intestinalis, 15,4% étaient les espèces parasitaires les plus fréquentes. Conclusion : Une diminution progressive de la proportion des sujets infectés allant de 52,2% en 2010 à 29,0% en 2015 a été constatée. Cela démontre un effet positif des efforts déployés par le gouvernement pour l’amélioration des conditions sanitaires à Bamako. Introduction: The invasion of the human digestive tract by parasites is the reason of several patients’ visits at the National Institute for Research in Public Health (INRSP). Objectives: The aim was to determine the prevalence of human intestinal parasites in patients admitted to the INRSP parasitology laboratory during the period from 2010 to 2015. That can enable to measure the impact of health situation improvement on the transmission of intestinal parasites in the human population in Bamako. Methodology: This was a retrospective study based on the information reported in the laboratory note books records. Results: A total of 1,833 individuals out of 3815 patients were detected positive. A prevalence of 44% was obtained in female subjects and 42.2% in male patients. The age groups 1-10 and 11-20 were more infected with 46.5%. Bambara ethnic group had the highest infection rate (46%) and the Tamasheks had the lowest rate (30%), while school kids and students were the most infected socio-professional group with 46.5%. Abdominal pain was the most common clinical signs. Entamoeba histolytica, 72% and Giardia intestinalis, 15.4% were the most common parasite species. Conclusion: A gradual decrease in the proportion of infected people ranging from 52.2% in 2010 to 29.0% in 2015 was found. This demonstrates a positive effect of the efforts made by the government to improve health conditions in Bamako

Mapping the Probability of Schistosomiasis and Associated Uncertainty, West Africa

We aimed to map the probability of Schistosoma haematobium infection being >50%, a threshold for annual mass praziquantel distribution. Parasitologic surveys were conducted in Burkina Faso, Mali, and Niger, 2004–2006, and predictions were made by using Bayesian geostatistical models. Clusters with >50% probability of having >50% prevalence were delineated in each country

Organomegaly in Mali before and after praziquantel treatment. A possible association with Schistosoma haematobium.

Continuous exposure to schistosome-infested water results in acute and chronic morbidity in all ages. We analysed occurence of organomegaly via ultrasonography and investigated a possible additive effect of dual-dose drug administration in 401 Schistosoma haematobium infected individuals from a highly endemic area in Mali. Mean intensity of infection at baseline (22.0 eggs per 10 ml) was reduced to 0.22 eggs per 10 ml 9 weeks after treatment (both treatments combined). Odds of persistent infection among those given dual-dose treatment was 41% of that in people given single dose (b = 0.41; p = 0.05; 95% CI 0.17-1.00), but after two years, 70.7% of the 157 participants, who completed the survey, were re-infected with no significant difference in prevalence and intensity of infection between treatment groups. Resolution of organomegaly occurred in all age groups after treatment. A novel association between Schistosoma haematobium infection and moderate portal vein enlargement was found in 35% (n: 55). Severe portal vein diameter enlargement was found in 3.2%. After two years, moderate hepatomegaly was present in 50.6%, moderate splenomegaly in 45.6% and moderate portal vein diameter enlargement in 19%. A subsequent dose of PZQ did not provide any additional long-term advantages

A Comparative Study of the Spatial Distribution of Schistosomiasis in Mali in 1984–1989 and 2004–2006

Geostatistical maps are increasingly being used to plan neglected tropical disease control programmes. We investigated the spatial distribution of schistosomiasis in Mali prior to implementation of national donor-funded mass chemotherapy programmes using data from 1984–1989 and 2004–2006. The 2004–2006 dataset was collected after 10 years of schistosomiasis control followed by 12 years of no control. We found that national prevalence of Schistosoma haematobium and S. mansoni was not significantly different in 2004–2006 compared to 1984–1989 and that the spatial distribution of both infections was similar in both time periods, to the extent that models built on data from one time period could accurately predict the spatial distribution of prevalence of infection in the other time period. This has two main implications: that historic data can be used, in the first instance, to plan contemporary control programmes due to the stability of the spatial distribution of schistosomiasis; and that a decade of donor-funded mass distribution of praziquantel has had no discernable impact on the burden of schistosomiasis in subsequent generations of Malians, probably due to rapid reinfection

Impact of different levels of supervision on the recovery of severely malnourished children treated by community health workers in mali

(1) Background: The Ministry of Health in Mali included the treatment of severe acute malnutrition (SAM) into the package of activities of the integrated community case management (iCCM). This paper evaluates the most effective model of supervision for treating SAM using community health workers (CHWs). Methods (2): This study was a prospective non-randomized community intervention trial with two intervention groups and one control group with different levels of supervision. It was conducted in three districts in rural areas of the Kayes Region. In the high supervision group, CHWs received supportive supervision for the iCCM package and nutrition-specific supervision. In the light supervision group, CHWs received supportive supervision based on the iCCM package. The control group had no specific supervision. (3) Results: A total of 6112 children aged 6-59 months with SAM without medical complications were included in the study. The proportion of cured children was 81.4% in those treated by CHWs in the high supervision group, 86.2% in the light supervision group, and 66.9% in the control group. Children treated by the CHWs who received some supervision had better outcomes than those treated by unsupervised CHWs (p < 0.001). There was no difference between areas with light and high supervision, although those with high supervision performed better in most of the tasks analyzed. (4) Conclusions: Public policies in low-income countries should be adapted, and their model of supervision of CHWs for SAM treatment in the community should be evaluated.publishedVersionPeer reviewe

Anemia and growth retardation associated with Schistosoma haematobium infection in Mali: a possible subtle impact of a neglected tropical disease.

BACKGROUND: The aim of this cross-sectional study was to investigate a possible association of Schistosoma haematobium with child growth development and describe a plausible schistosomiasis-related anemia in children and adults in a highly schistosomiasis endemic area of Mali. METHODS: Urine, feces and blood samples from 399 participants of both sexes (2-40 years of age) were analyzed and supplemented by anthropometric measurements. RESULTS: S. haematobium prevalence was 79.8%, S. mansoni 13.2% and Plasmodium falciparum 80.2%. S. haematobium infection intensity as five categories was significantly associated with anemia; i.e., odds of having anemia in the highest and the next highest category was 3.25 (95% CL 1.61-6.55; p<0.01) and 2.45 (95% CL 1.28-4.70; p<0.01), respectively, of that in the three lower categories combined after adjusting for age group and gender and the interaction between the two factors. Anemia was most pronounced in the 2-5 year olds males (55.5%, n=98). P. falciparum infection was not significantly associated with anemia. Stunting (body mass index [BMI] for age z-score<-2.00) was observed in 2.6% (2/78) of the 2-5 years olds and in 7.7% (14/182) in the 6-19 years age group. Lower BMI-z-scores (as continuous variable) were associated with anemia (p<0.05) while high intensity of S. haematobium infection was not significant when adjusting for age group and anemia. Participants with malaria infection had lower z-scores (as continuous variables) of weight and height for age. Lower height for age z-scores were also associated with anemia. CONCLUSIONS: S. haematobium infection is likely to impact on child growth and possibly also anemia in all age groups and advocates for inclusion of whole populations into future control programes

Prevalence of <i>Giardia intestinalis</i> Infection in Schistosomiasis-Endemic Areas in South-Central Mali

Intestinal parasite infections are frequent causes of diarrhea and malnutrition among children in the tropics. Transmission of helminths and intestinal protozoa is intimately connected with conditions of poverty, including inadequate sanitation and hygiene. Concurrent infections with several intestinal pathogens may lead to excess morbidity. Yet, there is a paucity of epidemiological data from Mali. In this study, stool samples from 56 individuals, aged 2&#8722;63 years, from Bamako and Niono, south-central Mali were examined for intestinal parasites using stool microscopy. Additionally, stool samples were subjected to a rapid diagnostic test (RDT) and polymerase chain reaction (PCR) for the detection of Cryptosporidium spp. and Giardia intestinalis. The predominant pathogens were Schistosoma mansoni and G. intestinalis with prevalences of 41% and 38%, respectively. Hymenolepis nana was detected in 4% of the participants, while no eggs of soil-transmitted helminths were found. Concurrent infections with G. intestinalis and S. mansoni were diagnosed in 16% of the participants. For the detection of G. intestinalis, PCR was more sensitive (100%) than RDT (62%) and microscopy (48%). As helminth-protozoa coinfections might have important implications for morbidity control programs, future studies should employ diagnostic tools beyond stool microscopy to accurately assess the co-endemicity of giardiasis and schistosomiasis

Rapidly boosted Plasma IL-5 induced by treatment of human <em>Schistosomiasis haematobium</em> is dependent on antigen dose, IgE and eosinophils

IgE specific to worm antigen (SWA) and pre-treatment eosinophil number, are associated with human immunity to re-infection with schistosomes after chemotherapeutic treatment. Treatment significantly elevates circulating IL-5 24-hr post-treatment of Schistosoma mansoni. Here we investigate if praziquantel treatment of human schistosomiasis haematobium also boosts circulating IL-5, the immunological and parasitological factors that predispose to this, and the relationship between these and subsequent immunity to post-treatment re-infection.The relationship between pre-treatment SWA-IgE, eosinophil number and infection intensity and the 24-hr post-treatment IL-5 boost was investigated in a Malian cohort (aged 5-40 yrs), exposed to S. haematobium. Eotaxin levels were measured at 24-hr post-treatment as a proxy of eosinophil migration. The relationship between the 24-hr post-treatment IL-5 boost and later eosinophil numbers and SWA-IgE levels (9-wk post-treatment) was examined, then investigated in the context of subsequent levels of re-infection (2-yr post-treatment). Circulating IL-5 levels increased 24-hr post-treatment and were associated with pre-treatment infection intensity, SWA-IgE levels, eosinophil number, as well as 24-hr post-treatment eotaxin levels. 24-hr IL-5 levels were, in turn, significantly associated with eosinophil number and elevated SWA-IgE 9-wk later. These SWA-IgE levels were significantly associated with immunity to re-infection.Early IL-5 production after treatment-induced exposure to S. haematobium worm antigen is positively associated with antigen dose (infection intensity), IgE availability for arming of effector cells at time of treatment and subsequent eosinophil migration response (as indicated by eotaxin levels). The IL-5 produced is positively associated with increased downstream eosinophil number and increases in specific IgE levels, implicating this cytokine boost and its down-stream consequences in the production and maintenance of IgE, and subsequent re-infection immunity

Significantly reduced intensity of infection but persistent prevalence of schistosomiasis in a highly endemic region in Mali after repeated treatment.

BACKGROUND: Preventive chemotherapy against schistosomiasis has been implemented since 2005 in Mali, targeting school-age children and adults at high risk. A cross-sectional survey was conducted in 2010 to evaluate the impact of repeated treatment among school-age children in the highly-endemic region of Segou. METHODOLOGY/PRINCIPAL FINDINGS: The survey was conducted in six sentinel schools in three highly-endemic districts, and 640 school children aged 7-14 years were examined. Infections with Schistosoma haematobium and S. mansoni were diagnosed with the urine filtration and the Kato-Katz method respectively. Overall prevalence of S. haematobium infection was 61.7%, a significant reduction of 30% from the baseline in 2004 (p<0.01), while overall prevalence of S. mansoni infection was 12.7% which was not significantly different from the baseline. Overall mean intensity of S. haematobium and S. mansoni infection was 180.4 eggs/10 ml of urine and 88.2 epg in 2004 respectively. These were reduced to 33.2 eggs/10 ml of urine and 43.2 epg in 2010 respectively, a significant reduction of 81.6% and 51% (p<0.001). The proportion of heavy S. haematobium infections was reduced from 48.8% in 2004 to 13.8% in 2010, and the proportion of moderate and heavy S. mansoni infection was reduced from 15.6% in 2004 to 9.4% in 2010, both significantly (p<0.01). Mathematical modelling suggests that the observed results were in line with the expected changes. CONCLUSIONS/SIGNIFICANCE: Significant reduction in intensity of infection on both infections and modest but significant reduction in S. haematobium prevalence were achieved in highly-endemic Segou region after repeated chemotherapy. However, persistent prevalence of both infections and relatively high level of intensity of S. mansoni infection suggest that more intensified control measures be implemented in order to achieve the goal of schistosomiasis elimination. In addition, closer monitoring and evaluation activities are needed in the programme to monitor the drug tolerance and to adjust treatment focus