[Epidemiological, clinical, evolutionary and risk factors of erysipelas in three hospitals in Nouakchott-Mauritania]. / Aspects epidemiologiques, cliniques, evolutifs et facteurs de risque de l'erysipele dans trois hopitaux de Nouakchott-Mauritanie.

INTRODUCTION: Erysipelas is an acute non-necrotizing dermohypoderma of bacterial origin, mainly due to streptococcus. Its elective topography is the leg, it is a frequent reason for consultation and hospitalization in medicine. This is a potentially serious medical emergency that can be life threatening. Our study aims to determine the epidemiological and clinical characteristics, as well as the risk and prognosis factors of erysipelas in Mauritania. PATIENTS AND METHODS: This was a cross-sectional descriptive observational study from January 01, 2016 to July 30, 2017. The study population was represented by patients seen for an acute inflammatory placard, hot, painful and feverish. RESULTS: In the 61 patients, the mean age was 40 years with extremes of 1 and 73 years. A female predominance was observed. The locations were one-sided. In 93.4% of cases, erysipelas was found in the lower limbs. Satellite lymphadenopathy was present in 40 patients, ie 66% of cases. A fever greater than or equal to 38 ° C was observed in 87% of cases, it was associated with chills 10% of cases. Local risk factors are represented by a traumatic wound, acute eczema and intertrigo inter toe. General factors are obesity, taking nonsteroidal anti-inflammatory drugs and artificial depigmentation. The outcome of our patients is favorable in 95% of cases on antibiotics. 9 patients presented with abscess during the course, ie 15%. CONCLUSION: In our study, erysipelas was observed mainly in a young housewife in her forties. Clinically, the preferred location was that of the leg found in 93.4%. Several risk factors are associated with erysipelas in our study.

INTRODUCTION: L'érysipèle est une dermohypodermite aiguë non nécrosante d'origine bactérienne, essentiellement due au streptocoque.Sa topographie élective est la jambe, il constitue un motif fréquent de consultation et d'hospitalisation en médecine. Il s'agit d'une urgence médicale, potentiellement grave pouvant engager le pronostic fonctionnel et vital. Notre étude a pour objectif de déterminer les caractéristiques épidémiologiques, cliniques, ainsi que les facteurs de risque et pronostic de l'érysipèle en Mauritanie. PATIENTS ET MÉTHODES: Il s'agissait d'une étude observationnelle descriptive transversale du 01 Janvier 2016 jusqu'au 30 Juillet 2017. La population d'étude était représentée par les patients consultant pour un placard inflammatoire aigu, chaud, douloureux et fébrile. RÉSULTATS: Chez les 61 patients recrutés, l'âge moyen était de40 ans avec des extrêmes de 1 et 73 ans. Une prédominance féminine était observée. Les localisations étaient unilatérales. Dans 93,4% des cas, l'érysipèle siégeait aux membres inférieurs. Une adénopathie satellite était présente chez 40 patients soit 66% des cas. Une fièvre supérieure ou égale à 38°c était observée dans 87% des cas, elle était associée à des frissons 10% des cas. Les facteurs de risque locaux sont représentés par une plaie traumatique, un eczéma aigu et un intertrigo inter orteil. Les facteurs généraux sont l'obésité, la prise d'anti-inflammatoires non stéroïdiens et la dépigmentation artificielle. L'évolution de nos patients est favorable dans 95% des cas sous antibiotiques. 9 patients présentaient une abcédation au cours de l'évolution soit 15%. CONCLUSION: Dans notre étude, l'érysipèle est observé surtout chez une jeune femme au foyer de la quarantaine. Sur le plan clinque, la localisation préférentielle était celle de la jambe retrouvée dans 93,4%. Plusieurs facteurs de risque sont associés à l'érysipèle dans notre étude.

[Computerized temperature monitoring of the vaccine cold chain in a tropical climate, Chad]. / Surveillance informatisée de la chaîne du froid en milieu tropical (Tchad).

Because new EPI liquid vaccines are highly sensitive to freezing and overheating, close monitoring of the cold chain is mandatory. The new Testostore 171-1 electronic thermometer (Testo) provides more reliable monitoring of cold chain temperature than freezer indicators, vaccine vial monitors and color strips that only indicate if vaccines are out-of-date. The Testo thermometer uses a probe placed in refrigeration units to periodically measure and store temperature readings. Temperature curves are displayed via a USB connection on a laptop computer running special software (Comfort software light). Testo temperature data can easily be communicated to all management levels by e-mail. The first experience using the Testo system in Africa involved regional EPI supervision in Mondou, Logone Occidental, Chad. After a preliminary mission in Chad in 2006 showed the feasibility of using this method to manage the national cold chain at all levels, a nurse was appointed as EPI supervisor and given a refresher course in Chad's capital Ndjamena in March 2009. In April-May 2009, the supervisor was sent back to the Logone Occidental Region to monitor, by himself, refrigeration units making up the regional and district cold chain for vaccine storage in five health centers (rural and urban). Temperature curve readings were performed on site in the presence of the medical staff and results were compared to those recorded twice a day on conventional temperature charts using lamellar thermometers installed in refrigerators doors. Testo curves showed that liquid vaccine storage temperatures fell below freezing too frequently and that temperatures readings of door thermometers were often inaccurate. Testo readings also detected power outages in refrigeration units used in urban settings and flame extinctions in kerosene lamp refrigerators due to refrigerator breakdown or windy weather conditions before the rainy season. The main advantage of this monitoring method is to provide reliable data as a basis not only for detection of possible freezing of liquid vaccines but also for discussion of cold chain management and improvement with medical staff.

[Diarrhea in urban agricultural workers in Nouakchott in Mauritania]. / La diarrhée chez les agriculteurs urbains de Nouakchott en Mauritanie.

Nearly 200 million people in the developing world are dependent or urban gardening for food and income. This practice has been accelerated by the droughts of recent decades which have forced more and more migrants into urban areas. Numerous potential health hazards have been attributed to urban gardening but the exact risks in Sahelian areas remain unclear. The purpose of this cross-sectional study was to evaluate the incidence of diarrhea at the Tel Zatar gardening site in urban Nouakchott, Mauritania. In addition, a case-control study was carried out to identify risk factors for diarrhea in function of gardeners' activity and living conditions. Statistical analysis was performed using univariate and logistical regression methods. The annual incidence of diarrhea ranged from 6.9 (IC95 p. 100 = 5.0-8.8) to 8.5 (IC95 p. 100 = 6.2-10.8) episodes per gardener and year. Multivariate analysis identified four significant risk factors. Two of these factors were unrelated to gardening, i.e., not having spent more than USD 3.50 the previous day (odds ratio (OR = 2.8, IC95 p. 100 = 1.01-7.81) and poor food hygiene (cooking outside (OR = 4.69, IC95 p. 100 = 1.06-20.83). The other two factors were regular consumption of raw vegetables (OR = 25.5, IC95 p. 100 = 2.0-32.0) and use of untreated well water (OR = 3.85, IC95 p. 100 = 1.08-14.29). Unprotected well water was the cause of 59.2 p. 100 of diarrheal episodes reported by gardeners at Tel Zatar. The results of this study confirm that vegetable production in urban gardens such as Tel Zatar is associated with health risks. Public health measures should address not only the garden sites but also domestic hygiene.

Host range and the maintenance of Haemonchus spp. in an adverse arid climate.

Three Haemonchus species (Haemonchus contortus, Haemonchus placei and Haemonchus longistipes) live in sympatry in Sahelian areas such as Mauritania (West Africa). Four host species (dromedary, zebu cattle, sheep and goats) share the same pastures for several months per year. Experimental infection by H. contortus or H. placei was achieved only poorly in dromedaries, and H. contortus or H. longistipes infection failed to establish in zebu cattle. Conversely, H. placei and H. longistipes successfully infected sheep and goats. Under field conditions, mixed congeneric infections were very rare in dromedaries but frequent in zebu cattle (H. contortus represented 16% of Haemonchus spp. burden), in sheep (H. placei: 15%) and in goats (H. placei: 9% and H. longistipes: 6% of worms). The importance of the different host species was evaluated for Haemonchus spp.: small ruminants are the main hosts of H. contortus, dromedaries harboured the large majority of H. longistipes worms but 5% of them were found in goats which seemed to be additional hosts. The most striking finding was the role played by the small ruminants in the survival strategy of H. placei in Sahelian regions: 56% of the total of H. placei worms were found in sheep, 34% in goats and only 10% in zebu cattle. These results are consistent with the hypothesis that the extension of host range plays an important role in the survival strategy of H. placei, whereas H. longistipes or H. contortus might well survive utilising their usual hosts.

Identification of Haemonchus species in domestic ruminants based on morphometrics of spicules.

An easy and rapid tool for the individual identification of Haemonchus species in domestic ruminants might be very useful in the study of natural populations, especially when two (or three) species are sympatric. Techniques based on cytology, cuticular-ridge patterns, sublateral hypodermic chords, or molecular biology allow species identification but are either expensive or time-consuming. Therefore, a discriminant function combining three measures of male spicules was established from experimental infections with H. contortus in both sheep and goats and with H. placei in zebu. The discriminant function was evaluated on individual worms and on average values obtained in natural and experimental populations throughout the world. It was compared with a previously established function. The use of our function permitted better species identification for all Haemonchus species of ruminants, including H. longistipes from camels and H. similis from cattle.

Adaptation to arid environment: Haemonchus longistipes in dromedaries of Saharo-Sahelian areas of Mauritania.

The adaptations of the trichostrongylid nematode Haemonchus longistipes of dromedaries (Camelus dromedarius) to the harsh environment of Saharo-Sahelian climate were assessed by means of (i) an epidemiological survey of dromedary infection in the south-west of Mauritania, (ii) an estimate over a 3 year period of parasite distribution within the host population and of prolificacy of H. longistipes females recovered from natural populations of infected dromedaries sampled at Nouakchott's slaughterhouse, and (iii) experimental infections of young dromedaries during three different periods of the year (end of the rainy season, middle and end of the dry season). Egg excretions (estimated by faecal egg counts), infective larvae derived from eggs as well as female prolificacy showed a marked seasonal pattern: high values in the rainy season and very low values in the dry season (especially March and April). Female prolificacy differed slightly between morphotypes: the knobbed type excreting over a longer period than the linguiform and smooth types. Following experimental infections in young dromedaries, arrest of larval development took place irrespective of the period. The survival strategy of H. longistipes in the dry season was based only on arrested larval development. Patent infections occurred from July to October, i.e. during the rainy season and was facilitated by the conjunction of high prevalence and intensity of adult worm burdens associated with high female prolificacy.

Experimental study of survival strategy of Haemonchus contortus in sheep during the dry season in desert areas of the Mauritania.

The survival of the most common worm of sheep and goats of desert areas, Haemonchus contortus, during the dry season is of the utmost importance. It may be achieved through long survival of adult worms that may preserve their ability to excrete viable eggs or to inhibited development in host and survival as a larval stage. Twelve lambs were experimentally infected with larvae obtained at the end of the rainy season. The resulting adult worms were able to survive and maintain their ability to produce viable eggs that developed into infective larvae up to 50 wk after infection. It is concluded that survival of adults during the dry season played a major role in transmission from 1 rainy season to the next, rather than inhibited development and survival as a larval stage.

Ecological, morphological and genetic characterization of sympatric Haemonchus spp. parasites of domestic ruminants in Mauritania.

The 4 species of ruminants (dromedary, zebu cattle, sheep and goat) in arid areas of Mauritania harboured Haemonchus spp. as the most frequent internal parasite. This was a rare situation where the 3 putative species, H. longistipes (dromedary), H. placei (zebu cattle) and H. contortus (sheep and goat) occurred sympatrically. The study was undertaken on hosts slaughtered at the Nouakchott abattoir, on the basis of monthly collection of worms. The environment was very unfavourable to H. placei and unfavourable to H. contortus, as intensity of infection remained low throughout the year, whereas infection in the dromedary was 10 to 20-fold higher. The survival strategies during the long, dry season were different: the surviving stages were either 4th-stage larvae in digesta (dromedaries), 4th-stage larvae either in digesta or mucosae (cattle), or 4th-stage larvae in mucosae and few adults (sheep and goats). The prolificacy of female worms, indicative of the potential to contaminate pastures, was similar for all Haemonchus spp. in the rainy season. H. longistipes behave differently during the pre-rainy season as no increase of prolificacy could be demonstrated as observed in the other species. Traits of vulvar morphology are considered as markers of ecological adaptation and were studied. The knobbed and smooth female morphs (in equal proportions) were the most frequent in H. longistipes, the knobbed morph out-numbered the other morphs in H. placei, and all 3 morphs were present in sheep and goats with the linguiform form being predominant. Genetic characterization of the 3 species was performed by means of Random Amplified Polymorphic DNA (RAPD). Three groups were obtained from analysis of these data: 1 group with individuals of H. contortus, 1 group with individuals of H. placei, and 1 group with individuals of H. longistipes. This indicated that, although the 3 species were valid, H. contortus and H. placei were more similar. Intraspecific variability was 2-fold higher in H. contortus than in the 2 other species. The ecological, morphological and genetical studies showed that H. longistipes, H. placei and H. contortus could be arranged in increasing order of variability.

Dry areas: an example of seasonal evolution of helminth infection of sheep and goats in southern Mauritania.

A total of 647 faecal egg counts and 53 necropsies were performed on sheep and goats originating from three sites of a Sahelian region of Mauritania (Gorgol) over a period of 2 years (1990-1992). Haemonchus contortus, Oesophagostomum columbianum and Stilesia globipunctata were the most prevalent species. The seasonal pattern was characterized by long survival of adults and high percentages of arrested fourth-stage larvae in the dry season, suggesting that two different strategies were used to survive from one rainy season to the next. Sheep and goats were equally infected, except for Stilesia globipunctata, which was found more often in sheep. The influence of age was limited, although kids and lambs born in the beginning of the dry season did not become infected until their first grazing in the rainy season.

[Camel trypanosomiasis caused by Trypanosoma evansi (Steel 1885), Balbiani 1888, in Islamic Republic of Mauritania: results of surveys in the Trarza region]. / La trypanosomose cameline à Trypanosoma evansi (Steel 1885), Balbiani 1888, en République islamique de Mauritanie: résultats d'enquêtes dans le Trarza.

A first survey concerning camel trypanosomiasis due to Trypanosoma evansi was carried out in the Trarza region (south-western Mauritania). Blood smears were made from 218 animals and 160 were submitted to an indirect immunofluorescence test. Young calves below one year old seem to be free of T. evansi infection, while in dairy females, average rates of infection of 7.3% (blood smears) and 24.5% (serological results) were found. The type of herd management seems to be an important risk factor: the herds that frequent, even temporarily, the wooded areas of the Senegal river valley or permanent water collections (R'kiz lake) show the highest infection rates. Recommendations are presented to camel rearing owners, especially those with dairy camel herds in the South of the country.

[Descriptive epidemiology of bovine theileriosis caused by Theileria annulata in Mauritania, Subsaharian West Africa]. / Epidémiologie descriptive de la theilériose bovine à Theileria annulata en Mauritanie, Afrique de l'Ouest sub-saharienne.

Tropical bovine theileriosis due to Theileria annulata has been discovered recently in Mauritania. An epidemiological study performed in the dry season allowed to better determine the serological prevalence of T. annulata infection and its associated factors. The sex does not seem to have any influence, the role of the breed could not be clearly established, whereas, the age, the geographical origin and the management of the herd have a significant influence on the serological prevalence. These results were compared with those of the tick fauna. Hyalomma dromedarii appears to be the natural vector over the whole Mauritanian territory. However, the more diversified the tick fauna is (lower valley of Senegal River), the highest is the serological prevalence. The incidence survey in the rainy season, performed exclusively in the Senegal River valley, raises the question of the role of Rhipicephalus evertsi evertsi, strictly limited to this area, which could be responsible for an amplifying phenomenon of transmission. The clinical survey in the dry season as well as in the rainy season did not reveal any clinical cases. Therefore, a stable endemic situation appears to exist between the local zebu and T. annulata infection in Mauritania.

[Efficacy and residual effect of amitraz (Taktic) on adult Hyalomma dromedarii in camels: preliminary trial]. / Efficacité et rémanence de l'amitraz (Taktic) sur les adultes de Hyalomma dromedarii chez le dromadaire: essai préliminaire.

Amitraz (12.5% emulsifiable concentrate) was tested against Hyalomma dromedarii of the one-humped camel in a dairy camel herd in Nouakchott (Mauritania), at a concentration of 0.025% of the active component. The efficacy on adult ticks and the rapid rate of tick detachment are clearly shown: 95% reduction within eight hours; however, the nymphs seem to be more resistant: only 50% reduction after eight hours. The residual activity of amitraz against Hyalomma dromedarii in camels is very short, less than 24 hours; furthermore, the amitraz treatment has no effect on survival, oviposition and the rate of egg hatching of females which attach in the first days following treatment. A discussion of likely causes of this phenomenon is presented.

[Trypanosomiasis caused by Trypanosoma evansi (Steel 1885), Balbiani 1888 in small ruminants in Mauritania: results of experimental inoculation and field surveys]. / La trypanosomose à Trypanosoma evansi (Steel 1885), Balbiani 1888 chez les petits ruminants de Mauritanie: résultats d'inoculation expérimentale et d'enquêtes sur le terrain.

In order to define the eventual role of small ruminants in the epidemiology of T. evansi infection in Southern Mauritania, the following experiments were carried out: the intravenous inoculation of a ewe and a goat with a local strain of T. evansi isolated from a dairy camel; surveys of small ruminant flocks which graze with infected camels in the South of the Trarza region. The experimental inoculation allowed to show that local sheep and goats are receptive. Only the ewe showed a clinical episode with loss of weight and abortion. During 220 days after inoculation the blood of the goat remained constantly infectious for the mouse whereas in the same period the ewe's blood showed an alternation of infectious and non-infectious phases. However in the field, none of 381 blood smears of small ruminants (207 goats, 174 sheep) were positive and none of the 187 serums (109 goats, 78 sheep). Therefore, it seems that the small ruminants of the South Mauritania do not play any role in the epidemiology of T. evansi camel trypanosomosis even if they are receptive to experimental inoculation.

Helminths of sheep and goats in desert areas of south-west Mauritania (Trarza).

Faecal samples were obtained from sheep and goats before, during and after the rainy season at three locations in south-west Mauritania. Several animals were also necropsied at the same time. Haemonchus contortus was the most prevalent worm. Infection by digestive-tract strongyles and Strongyloides papillosus was always very light (prevalence less than 20%). Sheep were more heavily infected than goats but animals under 1 year of age were not infected by digestive-tract strongyles. It is likely that young small ruminants became infected during the rainy season and that the parasites so acquired are inhibited in their development and/or survive nearly one year as adults.