Epidemiology of Malaria in the city of Kaedi (Mauritania, 2014).

BACKGROUND: In the face of ongoing and projected environmental and climate change, the epidemiology of malaria in the city of Kaédi (Mauritania), bordering the Senegal River Valley, requires special attention. OBJECTIVE: To describe the epidemiological situation of malaria in the city of Kaédi, Mauritania, during the wet season of 2014. METHODS: We conducted a descriptive cross-sectional survey in the city of Kaédi in september 2014 (wet season), to assess the prevalence of malaria parasites and vectors. For the choice of households, a cluster sampling was carried out and the city was subdivided into 10 sub-spatial units using a map of the city and the contribution of local populations. All household members were subjected to microscopic examination. In addition, larval surveys, morning wildlife sprays and night trap breaks were conducted. RESULTS: Of the 4671 thick drops made, three were positive, ie an average plasmid index of 0.06%. Prevalence was 0.04% (2/4671) and 0.02% (1/4671) for Plasmodium malariae and Plasmodium falciparum, respectively. In addition, the larval fauna consisted essentially of Culex larvae (100%). Two (2) female Anopheles mosquitoes were collected during the study. CONCLUSION: Even if transmission is low, in a context of absence of rainfall, the health authorities must foresee a strategy of malaria pre-elimination in riparian wilayas of the Senegal River.

Epidemiology of malaria and elimination prospects in Maghreb Countries.

BACKGROUND: Faced with the challenges of immigration, the opening of the Trans-Saharan road and the increase in the volume of trade with sub-Saharan Africa, there is a steady increase in the number of malaria cases. An introduction of the disease in the Maghreb is possible. OBJECTIVE: The general objective is to take stock of the epidemiological situation and the malaria control strategy in the Maghreb countries. METHODS: This is a synthesis of data from a literature search on: PubMed (publications), International and national reports (epidemiology and strategies). RESULTS: In 1979, Tunisia became the second Maghreb country to eliminate malaria after Libya (the last local case in 1973). In 1997, when 76 cases were recorded, Morocco embarked on a new national strategy aimed at the elimination of indigenous malaria by the end of 2005. In Algeria, after a phase of control by existence of P. vivax and P. malaria microspheres, the country is in the maintenance phase and no cases were recorded between 2013 and 2016. In Mauritania, even though malaria transmission is generally low, this parasitosis remains a problem public health. And the strategies of struggle and the contribution of scientific research remain below expectations. CONCLUSION: With the exception of Mauritania, the countries of the Great Arab Maghreb have practically eradicated malaria, even though the maintenance phase is underway in Algeria and cases imported from sub-Saharan Africa continue to be registered.

Bibliometry of biomedical scientific publications in Mauritania (Medline:1992-2016).

BACKGROUND: As part of the preparatory work for the elaboration of a strategic plan for the development of scientific research in Mauritania, an overview of national biomedical research was recommended by the supervisory authorities. AIM: Describe the bibliometric profile of biomedical scientific publications in Mauritania, indexed in Medline database, over the past 25 years. METHODS: A bibliometric study was carried out on Medline Database covering the period from 1 January 1992 to 31 December 2016. Were retained, the scientific papers whose one of the author's address, at least, was a Mauritanian one. The fields of the Medline display format were used to describe the following items: authors, addresses, journal, language, article type, and Mesh terms. The assignment of a publication to an author was limited to the first and last position. Only first institutional affiliation mentioned in the authors' addresses was considered to classify the establishments' productivity. International co-operation has been studied through the compilation of all co-author addresses. RESULTS: Between 1992 and 2016, Medline had indexed 141 Mauritanian articles, 74 of them was published during the previous five-year period (2012-2016). These papers covered essentially the following disciplines: "Infectious diseases", "Community health", "Parasitology", "Veterinary Medicine" and "Marine Sciences" It mainly consist of an original article (79%), written in English (57%) and published without financial support (72%). Mauritanian articles have been published in 72 journals in 12 different countries. Three journals « Bulletin de la Société de Pathologie Exotique ¼, « Pan African Medical Journal ¼ and « Malaria journal ¼ have accounted 23 % of the publications ; 36% of the papers have been published in French journals. The research subjects of the Mauritanian biomedical literature was carried out via 215 major keywords, five of them represented 22% of the publications: «Malaria¼, «HIV infections¼, «Anopheles¼,  «Camels¼, and «Goat diseases ¼". For 112 scientific articles (79%), the first author were Mauritanian, as for the rest (n = 29) the authors were coming from 15 different countries, mainly from France, Senegal and the Arab Maghreb. In 48% of the articles, the affiliation of the first author was one of four following structures: « the National Hospital Centre in Nouakchott¼, «The National Center for Livestock and Veterinary Research¼, « the Faculty of Science and Technology ¼ and «the National Institute for Research in Public Health¼. A partnership with an international team was noted for 40% of publications, particularly with France, Italy, Senegal, Burkina Faso and Tunisia. CONCLUSION: During the last past 25 year, the biomedical publication feature, inconsistently growing since 2012, has been characterizing by the adequacy of research themes with the population's health needs, an international visibility and an extensive networking with many foreign research structures. Strengthening Maghrebian collaboration in the fields of research training and Multi-centric research would be a fine support to the national dynamics of biomedical research.

Malaria in three epidemiological strata in Mauritania.

BACKGROUND: Malaria epidemiology in Mauritania has been characterized on the basis of epidemiological strata, defined by climatic and geographic features, which divide the country into three zones: Sahelian zone, Sahelo-Saharan transition zone, and Saharan zone. The association between geographic stratification and malaria transmission was assessed through a series of parasitological and entomological surveys. METHODS: Surveys were conducted during the 'cool' dry season in 2011, 'hot' dry season in 2012, and rainy season in 2013 in a total of 12 sentinel sites. Finger-prick capillary blood samples were collected from children aged 2-9 years old in randomly selected households for microscopic examination and rapid diagnostic test for malaria. Adult mosquitoes were sampled by pyrethrum spray catch and CDC light traps and identified using morphological keys and molecular tools. RESULTS: Of 3445 children included, 143 (4.15 %) were infected with malaria parasites including Plasmodium falciparum (n = 71, 2.06 %), Plasmodium vivax (57, 1.65 %), P. falciparum-P. vivax (2, 0.06 %), Plasmodium ovale (12, 0.35 %), and Plasmodium malariae (1, 0.03 %). A large majority of P. falciparum infections were observed in the Sahelo-Saharan zone. Malaria prevalence (P < 0.01) and parasite density (P < 0.001) were higher during the rainy season (2013), compared to cool dry season (2011). Plasmodium vivax was mainly observed in the Saharan region [43 of 59 (73 %) P. vivax infections], mostly in Nouakchott districts, with no significant seasonal variation. Of 3577 mosquitoes captured, 1014 (28.3 %) belonged to Anopheles spp. Anopheles gambiae was the predominant species in all three epidemiological strata during the 'cool' dry season in 2011 but was absent in all study sites, except for Teyarett district in Nouakchott, during the 'hot' dry season in 2012. During the rainy season in 2013, An. gambiae, Anopheles arabiensis, Anopheles pharoensis, and Anopheles rufipes were abundant in different zones. CONCLUSIONS: The results of the present study support the stratification of malaria in Mauritania. However, the Sahelian zone had the lowest malaria prevalence, while the Sahelo-Saharan zone had the highest malaria burden. Local changes due to anthropogenic factors (i.e., human migration, urbanization, malaria interventions) should be considered in order to optimize the control strategy.

Epidemiology of intestinal parasitosis in schoolchildren in the Moughatâa of Riyadh (Nouakchott).

INTRODUCTION: Intestinal parasitoses are very common in school and in Mauritania few external studies address the issue. Several risk factors are known for intestinal parasitosis, including fecal danger, promiscuity and contaminated food Objective: To describe the epidemiology of intestinal parasitosis in school-age children in the Moughatâa (department) of Riyadh in Nouakchott (Mauritania) and the associated risk factors. METHODS: This was a descriptive cross-sectional study lasting three months, at the level of a random sample of pupils enrolled in five primary schools in the Moughatâa of Riyadh, as well as the foods sold in front of the establishments included. The data was collected through an anamnestic and clinical observation grid, as well as stool and food samples exposed in front of the schools included. The parasitological examination of the stools was carried out at the National Institute of Public Health Research (INRSP) in Nouakchott, by the methods of modified Ritchie and Kato-Katz. For food, a microbiological analysis looking for fecal colibacilli is carried out. RESULTS: The study population was composed of 337 students with a sex ratio of 0.76. The prevalence of parasitosis in the study population was 46% (95% CI [40.75%-51.33%]): Boys (48.6%), 95% CI [40.66%-56.67%]); Girls (43.9%), 95% CI [37.13%-51.07%]. The spectrum of these parasitic intestinal diseases was dominated by protozoa (51.6%) and helminthiasis represented 10.4% and characterized by mono parasitism (31.8%). The food sold in front of the schools studied was contaminated with coli bacteria, in 54.5% of cases. CONCLUSION: The high prevalence of intestinal parasitosis in the primary schools studied and the contamination of food sold to students, require the strengthening of the strategy to fight against diseases of fecal peril and school and public hygiene, in the Moughatâa of Riyadh (Nouakchott).

[Seasonal transmission of malaria in the Senegal River Valley: case study of the city of Kaedi-Mauritanie]. / Transmission saisonnière du paludisme au niveau de la vallée du fleuve Sénégal: cas de la ville de Kaédi-Mauritanie.

INTRODUCTION: In the face of environmental and climatic changes both ongoing and planned, the epidemiology of malaria in the city of Kaedi (Mauritania), along the Senegal River Valley, requires special attention. Some cases of malaria have been registered in the health facilities throughout the year, with an average of 150,000 annual suspected cases and climatic and ecological conditions which are now favorable for seasonal transmission. METHODS: We conducted two cross-sectional descriptive surveys in the city of Kaedi in September 2014 (wet season) and in May 2015 (dry season). Our cluster sampling involved 700 households. Microscopic examination was performed in all household members. Furthermore, larval surveys, early morning wildlife spraying and nocturnal traps breaking were performed. RESULTS: During both seasons, 9.313 thick smears were manufactured, 15 were positive, with a plasmodium prevalence rate of 0.16%. Among these, 12 were positive in the dry season and 3 in the rainy season. Plasmodium prevalence rate was 0.26% and 0.06% respectively in the dry season (n = 4642) and in the wet season (n = 4671). In the rainy season, rates were 0.04% (2/4671) and 0.02% (1/4671) respectively for Plasmodium malariae and Plasmodium falciparum. The only species found in the dry season was Plasmodium falciparum. Entomological investigations showed the presence of a single species of Anopheles mosquito, Anopheles gambia (two in the rainy season and six in the dry season). Larval surveys showed that the larval fauna was dominated by Culex larvae (99.6%). Anopheles larvae (0.4%) were collected only during the dry season. CONCLUSION: Despite low malaria transmission in the city of Kaedi, in a context of lack of rainfall, health authorities should implement a strategy for malaria elimination in the wilayas of the Senegal River.

Management crisis of health personnel in the great Maghreb. Mauritania case study.

OBJECTIVE: To describe the number and distribution of health personnel in Mauritania during 2017, according to their academic grades and administrative assignments. METHODS: This is a quantitative study of the number and uses of health human resources in Mauritania, based on the 2017 data from the Personnel Register of the Ministry of Health. The number of doctors, midwives and nurses in the six administrative regions of Mauritania and its "wilayas", were standardized according to the size of the population (health workers /10 000 inhabitants). Interregional inequalities in the allocation of health personnel have been studied through the correlation between the percentages of the health professions and the populations of the regions affected. RESULTS: In 2017, the number of health workers in all categories was 6608 in Mauritania, a ratio of 17.5 / 10000 health workers / inhabitants, ranging from 8.6 in "Gargot" wilaya to 37.3 in the wilaya of "Inchiri". The densities of specialist physicians, general practitioners, midwives and nurses were respectively 0.9, 0.84, 1.8, and 3.32 per 10,000 inhabitants, respectively. In the Nouakchott region, covering 28.5% of the Mauritanian population, 76.5% of specialist doctors and 56.8% of midwives, had ratios (health workers / 10 000 inhabitants) two and three times higher than national levels. CONCLUSION: This study documented on the one hand the persistence of the shortage of health personnel in Mauritania in 2017, in all its professional categories, and on the other hand the inequalities of their distribution in its administrative zones, with a relative abundance in the region of Nouakchott.

Distribution of Plasmodium spp. infection in asymptomatic carriers in perennial and low seasonal malaria transmission settings in West Africa.

BACKGROUND: Since 2000, substantial progress has been made in reducing malaria worldwide. However, some countries in West Africa remain a hotspot for malaria with all age groups at risk. Asymptomatic carriers of Plasmodium spp. are important sources of infections for malaria vectors and thus contribute to the anchoring of the disease in favourable eco-epidemiological settings. The objective of this study was to assess the asymptomatic malaria case rates in Korhogo and Kaedi, two urban areas in northern Côte d'Ivoire and southern Mauritania, respectively. METHODS: Cross-sectional surveys were carried out during the rainy season in 2014 and the dry season in 2015 in both settings. During each season, 728 households were randomly selected and a household-based questionnaire was implemented to collect demographic and epidemiological data, including of malaria preventive methods used in communities. Finger-prick blood samples were obtained for biological examination using microscopy and rapid diagnostic tests (RDTs). RESULTS: Overall, 2672 households and 15 858 consenting participants were surveyed. Plasmodium spp. infection was confirmed in 12.4% (n = 832) and 0.3% (n = 22) of the assessed individuals in Korhogo and Kaedi, respectively. In Korhogo, the prevalence of asymptomatic malaria was 10.5% (95% CI: 9.7-11.2) as determined by microscopy and 9.3% (95% CI: 8.6-10.0%) when assessed by RDT. In Kaedi, asymptomatic malaria prevalence was 0.2% (95% CI: 0.1-0.4%) according to microscopy, while all RDTs performed were negative (n = 8372). In Korhogo, asymptomatic malaria infection was significantly associated with age and season, with higher risk within the 5-14 years-old, and during the rainy season. In Kaedi, the risk of asymptomatic malaria infection was associated with season only (higher during the dry season; crude OR (cOR): 6.37, 95% CI: 1.87-21.63). P. falciparum was the predominant species identified in both study sites representing 99.2% (n = 825) in Korhogo and 59.1% (n = 13) in Kaedi. Gametocytes were observed only in Korhogo and only during the rainy season at 1.3% (95% CI: 0.7-2.4%). CONCLUSIONS: Our findings show a low prevalence of clinical malaria episodes with a significant proportion of asymptomatic carriers in both urban areas. National policies for malaria infections are focused on treatment of symptomatic cases. Malaria control strategies should be designed for monitoring and managing malaria infections in asymptomatic carriers. Additional measures, including indoor residual spraying, effective use of long-lasting insecticidal nets is strongly needed to reduce the number of Plasmodium spp. infections in Korhogo and Kaedi.

Prevalence and seasonal transmission of Schistosoma haematobium infection among school-aged children in Kaedi town, southern Mauritania.

BACKGROUND: Mauritania is at the fringe of transmission of human schistosomiasis, which mainly occurs in the southern and southeastern parts of the country. This study aimed to assess the influence of rainfall seasonality on the prevalence of Schistosoma haematobium infection among school-aged children in Kaedi, southern Mauritania. METHODS: Cross-sectional surveys (i.e. parasitological, malacological and observations on water-related human activities) were carried out in Kaedi between September 2014 and May 2015, during both the wet and dry seasons. A total of 2162 children aged 5-15 years provided a single urine sample that was subjected to S. haematobium diagnosis. Snails were sampled and checked for cercarial shedding. Water contact patterns of the local population were recorded by direct observation. RESULTS: The prevalence of S. haematobium was 4.0% (86/2162, 95% confidence interval (CI): 3.2-4.9%) with a geometric mean egg count per 10 ml of urine of 3.7 (95% CI: 2.8-4.3). Being male (adjusted odds ratio (aOR) 1.78, 95% CI: 1.13-2.80), being at primary school (aOR 1.73, 95% CI: 1.04-2.87) and dry season (aOR 0.56, 95% CI: 0.35-0.89) were significantly associated with S. haematobium. Among 284 potential intermediate host snail specimens collected over the rainy and dry seasons, three species were identified: Bulinus senegalensis (n = 13) and B. forskalii (n = 161) in the rainy season, and B. truncatus (n = 157) in the wet season. No snail was shedding cercariae. On average, seven human water contacts were recorded per hour per observer over a 28-day observation period. Twelve types of water contact activities were identified among which, swimming/bathing was predominant (n = 3788, 36.9%), followed by washing clothes (n = 2016, 19.7%) and washing dishes (n = 1322, 12.9%). Females (n = 5270, 51.4%) were slightly more in contact with water than males (n = 4983, 48.6%). The average time spent in the water per person per day was 14.2 min (95% CI: 13.8-14.6 min). The frequency and duration of water contact followed a seasonal pattern. CONCLUSION: Our findings demonstrate a low prevalence and intensity of S. haematobium among school-aged children in Kaedi. Appropriate integrated control measures, including health education among at-risk communities and snail control may help to interrupt transmission of S. haematobium in Kaedi.

Surface composition XPS analysis of a plasma treated polystyrene: Evolution over long storage periods.

A polystyrene surface (PS) was initially treated by cold nitrogen and oxygen plasma in order to incorporate in particular amine and hydroxyl functions, respectively. The evolution of the chemical nature of the surface was further monitored over a long time period (580 days) by chemical assay, XPS and contact angle measurements. Surface density quantification of primary amine groups was performed using three chemical amine assays: 4-nitrobenzaldehyde (4-NBZ), Sulfo succinimidyl 6-[3'(2 pyridyldithio)-pionamido] hexanoate (Sulfo-LC-SPDP) and iminothiolane (ITL). The results showed amine densities were in the range of 2 per square nanometer (comparable to the results described in the literature) after 5min of nitrogen plasma treatment. Over the time period investigated, chemical assays, XPS and contact angles suggest a drastic significant evolution of the chemical nature of the surface within the first two weeks. Beyond that time period and up to almost two years, nitrogen plasma modified substrates exhibits a slow and continuous oxidation whereas oxygen plasma modifed polystyrene surface is chemically stable after two weeks of storage. The latter appeared to "ease of" showing relatively mild changes within the one year period. Our results suggest that it may be preferable to wait for a chemical "stabilization" period of two weeks before subsequent covalent immobilization of proteins onto the surface. The originality of this work resides in the study of the plasma treated surface chemistry evolution over long periods of storage time (580 days) considerably exceeding those described in the literature.

Elucidation of innovative antibiofilm materials.

It is known for roughly a decade that bacterial communities (called biofilms) are responsible for significant enhanced antibiotherapy resistance. Biofilms are involved in tissue persistent infection, causing direct or collateral damage leading to chronic wounds development and impairing natural wound healing. In this study, we are interested in the development of supported protein materials which consist of asymmetric membranes as reservoir supports for the incorporation and controlled release of biomolecules capable of dissolving biofilms (or preventing their formation) and their use as wound dressing for chronic wound treatment. In a first step, polyhydroxyalkanoates (PHAs) asymmetric membranes were prepared using wet phase inversion technique. Scanning microscopy (SEM) analysis has showed the influence of different processing parameters. In a second step, the porous side of the membranes were functionalized with a surface treatment and then loaded with the antibiofilm agent (dispersin B). In a third step, the properties and antibiofilm performance of the loaded-membranes were evaluated. Exposure of Staphylococcus epidermidis biofilms to such systems weakly inhibited biofilm formation (weak preventive effect) but caused their detachment and disaggregation (strong curative effect). These initial results are promising since they open the way to a new generation of effective tools in the struggle against persistent bacterial infections exhibiting enhanced antibiotherapy resistance, and in particular in the case of infected chronic wounds.

Absence of dry season Plasmodium parasitaemia, but high rates of reported acute respiratory infection and diarrhoea in preschool-aged children in Kaédi, southern Mauritania.

BACKGROUND: The epidemiology of malaria in the Senegal River Gorgol valley, southern Mauritania, requires particular attention in the face of ongoing and predicted environmental and climate changes. While "malaria cases" are reported in health facilities throughout the year, past and current climatic and ecological conditions do not favour transmission in the dry season (lack of rainfall and very high temperatures). Moreover, entomological investigations in neighbouring regions point to an absence of malaria transmission in mosquito vectors in the dry season. Because the clinical signs of malaria are non-specific and overlap with those of other diseases (e.g. acute respiratory infections and diarrhoea), new research is needed to better understand malaria transmission patterns in this region to improve adaptive, preventive and curative measures. METHODS: We conducted a multipurpose cross-sectional survey in the city of Kaédi in April 2011 (dry season), assessing three major disease patterns, including malaria. Plasmodium spp. parasite rates were tested among children aged 6-59 months who were recruited from a random selection of households using a rapid diagnostic test and microscopic examination of Giemsa-stained thick and thin blood films. Acute respiratory infection and diarrhoea were the two other diseases investigated, administering a parental questionnaire to determine the reported prevalence among participating children. FINDINGS: No Plasmodium infection was found in any of the 371 surveyed preschool-aged children using two different diagnostic methods. Acute respiratory infections and diarrhoea were reported in 43.4% and 35.0% of the participants, respectively. About two thirds of the children with acute respiratory infections and diarrhoea required medical follow-up by a health worker. CONCLUSIONS: Malaria was absent in the present dry season survey in the capital of the Gorgol valley of Mauritania, while acute respiratory infections and diarrhea were highly prevalent. Surveys should be repeated towards the end of rainy season, which will enhance our understanding of the potential changes in malaria transmission in a region known as 'hot spot' of predicted climate change.