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O Faye

Publications and source records attributed to O Faye.

At least 19 recordsLinked to original sources
PubMed1999

[Experimental transmission of Crimean-Congo hemorrhagic fever virus: role of 3 vector species in the maintenance and transmission cycles in Senegal].

In this article, we published the role of three species of ticks Amblyomma variegatum (Fabricius, 1974), Hyalomma marginatum rufipes (Koch, 1844) and Hyalomma truncatum (Koch, 1844) in the maintenance and transmission of the CCHF virus. The imagos of these species were infected by intracoelomic route. Vertical transmission (transtasial and transovarial) and horizontal transmission for different stases were studied by isolation on newborn mice, polymerase chain reaction, indirect immunofluorescence and ELISA. Our results proved that 15 days after inoculation, infection rates of 100% were noted with Hyalomma marginatum rufipes and Hyalomma truncatum. This rate is about 60% for Amblyomma variegatum. The imagos of the three species infected have transmitted the virus to their host during blood feeding (100%). A high transovarial transmission for Hyalomma marginatum rufipes and Hyalomma truncatum were observed (respectively 53 and 50%). This rate is about 12% for Amblyomma variegatum. The tick infection does not persist up to the first generation for the three species studied. Ticks are temporary reservoirs vectors but not permanent reservoirs of CCHF virus.

Animals↗
PubMed1999

Status of pyrethroid resistance in Anopheles gambiae sensu lato.

The present study confirms the presence of pyrethroid resistance among Anopheles gambiae s.l mosquitos in Côte d'Ivoire and reports the observation of such resistance in two other countries in West Africa (Benin and Burkina Faso). Malaria vector populations from Cameroon (Central Africa), Senegal (West Africa) and Botswana (southern Africa) were found to be susceptible to pyrethroids. In the most resistant mosquito populations, resistance to permethrin was associated with reduced mortality, not only with respect to this compound but also towards deltamethrin. Moreover, a significant increase in knockdown time was observed in some mosquito populations before any decrease in mortality, suggesting that knockdown time could be a good indicator for the early detection of pyrethroid resistance. In view of the current extension of such resistance, there is an urgent need to set up a network in Africa to evaluate its development. It is also vital that the impact of this resistance on pyrethroid-impregnated bednets be assessed.

Africa↗
PubMed1998

Origin and prevention of airport malaria in France.

Since 1969, 63 cases of airport malaria have been reported in Western Europe, 24 of which occurred in France. Most were due to Plasmodium falciparum. In 1994, 7 cases occurred in and around Roissy Charles de Gaulle airport (CDG), showing 4 types of contamination: among employees working on airstrips or opening containers, among residents living near the airport, among people living at some distance from the airport after a secondary transport of vectors, and by vectors transported in luggage. In-flight or stop-over infection is not considered as airport malaria. The infective anophelines originated from airports where malaria transmission occurs, mostly in subsaharan Africa. A tentative list is given taking into account aerial traffic with France. Surveys in the airports of Dakar (Senegal), Cotonou (Benin), Abidjan (Cote d'Ivoire) and Yaoundé (Cameroun) found potential vectors in all of these from July to September. After 1994, the Contrôle Sanitaire aux Frontières (CSF) in charge at CDG concentrated its efforts on the flights at risk, as well as information and sensitization of airline companies, which resulted in 73% and 87% of the flights at risk being properly disinsected in 1995 and 1996. Despite pyrethroid resistance in Anopheles gambiae s.s. in West Africa, the efficacy of aircraft spraying with permethrin aerosols is still acceptable. However, surveillance of resistance should be improved and search for nonpyrethroid insecticides suitable for aircraft strongly encouraged.

Africa, Western↗
PubMed1998

Skin diseases in Bamako (Mali).

BACKGROUND: Skin diseases have only recently been considered as a possible public health problem in developing countries. Data supporting this matter are scarce. The aim of this study is to report the experience of a specialized dermatologic center in Bamako (Mali) in order to complete two previous studies conducted in the Bamako area: a prevalence study in the general population and a study in nonspecialized health centers of Bamako. It is our intention to provide a comprehensive picture of the problem of skin diseases in an African developing country. METHODS: We retrospectively collected all cases of skin diseases diagnosed during consultations provided at the Institut Marchoux in Bamako, the only center specializing in dermatology in Mali, during the year 1993. RESULTS: A total of 10,575 new outpatients were seen with 10,889 skin diseases. The main skin diseases registered were as follows: infectious dermatoses (41% of all diagnoses, including scabies (16.6%), superficial mycoses (13.6%), and primary pyoderma (5.6%)), dermatitis (20.4%), papular urticaria (4.4%), acne (4.2%), pityriasis alba (3.6%), keratoderma (3.6%), and urticaria (3%). Typical tropical infectious diseases accounted for only 1% of all diagnoses. CONCLUSIONS: It appears that certain skin diseases (mainly scabies and pyoderma) are an important health problem for the population of the Bamako area. Public health policies should be implemented in order to manage this problem rationally.

Acquired Immunodeficiency Syndrome↗
PubMed1998

[Interepidemic supervision of the leishmania focus of Keur Moussa (Thies, Senegal)].

A supervision of the focus of human cutaneous leishmaniasis of Keur Moussa has been carried out in 1988-1989 and in 1991-1992. Among the 13 species gathering the 10,144 phlebotomine sandflies trapped, two belong to genus Phlebotomus, the others to genus Sergentomyia. Phlebotomus duboscqi, that has been found out by Deded et al. in 1980 as the vector of this leishmaniasis in Senegal, is the most represented species after Sergentomyia schwetzi, with respectively 32.3 and 28.5% of the found during these two periods. It is twice more abundant and frequent in the monastery area than the religious one. This difference may be due to the better micro-climatic conditions, the abundance of rodents and the human proximity. After the rainy seasons that influence a lot P. duboscqi's activity, the density of phlebotomine sandflies makes a progressive rise, as well as the temperature and humidity, to reach two maxima in April-May and July-August. Parasitological studies on females of phlebotomine sandflies and rodents Arvicanthis niloticus, Mastomys erythroleucus and Cricetomys gambianus are negative. This focus seems to be again in an inter-epidemic phase.

Animals↗
PubMed1998

[Intestinal parasites in the vendors and consumers of street food. A study conducted in the Dakar area].

In order to assess the parasitic risk for street-food consumers, the authors conducted two studies from September to August 1996, one on street-food sellers (305) and the other on consumers (235). Among the consumers, 127 were considered as not exposed to risk, since they did not frequent the sector being surveyed, and 108 were exposed because they consumed at least one meal per day cooked by the sellers of this area. Both groups filled out a questionnaire and had their stools analysed according to the RITCHIE method. The infection rate was 60% among sellers and 45.5% among consumers. Protozoans were predominant in both groups. Among the consumers, those exposed were significantly more infected. Even though the sellers represent a parasitic risk due to their level of infection and the typology of parasites they shelter, one cannot assume that consumers are contaminated only by the sellers of street food. However, appropriate measures must be implemented in order to minimize risks for street-food consumers.

Feces↗
PubMed1998

Subulura saloumensis n. sp. (Nematoda, Subuluroidea) from four species of rodents in Senegal.

A new species of the genus Subulura is described from 4 new rodent hosts: Arvicanthis niloticus, Mastomys erythroleucus, Mastomys huberti, and Tatera gambiana. Subulura saloumensis n. sp. differs from the congeneric species by the morphology of its head. the absence of buccal lobes, the length of right and left spicules, the absence of caudal alae, and the existence of a caudal papillae with a sensorial bristle. The latter, which we observe for the first time in specimens gathered from M. huberti, has never previously been described in a species of the genus Subulura.

Animals↗
PubMed1998

Evolution of malaria in Africa for the past 40 years: impact of climatic and human factors.

Different malarial situations in Africa within the past 40 years are discussed in order to evaluate the impact of climatic and human factors on the disease. North of the equator, more droughts and lower rainfall have been recorded since 1972; and in eastern and southern Africa, there have been alternating dry and wet periods in relation to El Niño. Since 1955, the increase in human population from 125 to 450 million has resulted in both expansion of land cultivation and urbanization. In stable malaria areas of West and Central Africa and on the Madagascar coasts, the endemic situation has not changed since 1955. However, in unstable malaria areas such as the highlands and Sahel significant changes have occurred. In Madagascar, cessation of malaria control programs resulted in the deadly epidemic of 1987-88. The same situation was observed in Swaziland in 1984-85. In Uganda, malaria incidence has increased more than 30 times in the highlands (1,500-1,800 m), but its altitudinal limit has not overcome that of the beginning of the century. Cultivation of valley bottoms and extension of settlements are in large part responsible for this increase, along with abnormally heavy rainfall that favored the severe epidemic of 1994. A similar increase in malaria was observed in neighboring highlands of Rwanda and Burundi, and epidemics have been recorded in Ethiopia since 1958. In contrast, in the Sahel (Niayes region, Senegal), stricken by droughts since 1972, endemic malaria decreased drastically after the disappearance of the main vector, Anopheles funestus, due to the destruction of its larval sites by cultivation. Even during the very wet year of 1995. An funestus did not reinvade the region and malaria did not increase. The same situation was observed in the Sahelian zone of Niger. Therefore, the temperature increase of 0.5 degree C during the last 2 decades cannot be incriminated as a major cause for these malaria changes, which are mainly due to the combination of climatic, human, and operational factors.

Africa South of the Sahara↗
PubMed1998

[Malaria in the southern sanitary district of Dakar (Senegal). 1. Parasitemia and malarial attacks].

A survey of endemic malaria in Dakar was carried out in the southern sanitary district covering the city centre and neighbouring areas. The survey was scheduled from June 1994 to May 1995 in 12 sites distant from each other by 1000 to 1500 meters. Clinical and parasitological data were collected during weekly medical follow-ups at the patients' home with the systematic research of Plasmodium once a month. The study included 2,337 persons aged between 1 month and 88 years and belonging to 284 volunteer resident families. Through monthly parasitological examinations, a parasite rate (P.R.) of 0.3% and a gametocyte rate (G.R.) of 0.005% were recorded. Only Plasmodium falciparum was observed. The P.R. varied according to age: from 0.1% in the children under 2 years to 0.7% in the young adults (15-20 years) who appeared significantly more affected than the other age groups, including that of children from 2 to 9 years, of whom only 0.3% were infected by the parasite. The P.R. varied also according to the site surveyed: from 0% in the city centre to 1.3% at the periphery of the sanitary district and according to the time of year, reaching its height of 0.8%, between October and December, that is just after the rainy season. At the end of the year of survey, 929 among those surveyed were considered to have been satisfactorily followed. Their annual incidence rate was 2.4% for the parasitemia and of 1.5% for the malaria attacks. None of the participants aged under 2 years had the parasite. Among the others, the annual incidence rate varied according to the age--although not significantly--passing from 1.1% to 5.3% for parasitemia and from 0.4% to 3.0% for malaria attacks. Theses rates did not differ significantly according to site; the cases registered varied between 1% and 8% for parasitemia and 1% and 5.8% for malaria attacks. Only 10.6% of febrile subjects suffered from malaria attacks, but this rate seemed to go up between October to December, rising to 26.6% which corresponds to 1 case of malaria attacks for 4 cases of hyperthermia in that period. Weak density of Anopheline population and satisfactory medical surveillance explain the recorded results.

Adolescent↗
PubMed1998

[Toxoplasmosis in Dakar. Seroepidemiologic sampling of 353 women of reproductive age].

Thanks to a serological survey carried out in Dakar from January to November 1993 among 353 procreative women, immune cover regarding toxoplasmosis was assessed using ELISA methodology: 40.2% of the surveyed population had antibodies of toxoplasmosis. No evidence of age, pregnancy, number of previous pregnancies was noted in antitoxoplasmosis antibodies prevalence. The seroconversion risk seems to be low even when it has existed during pregnancy. Contamination occurred during childhood. Some sanitary education should be provided to the procreative population in order to achieve a better compliance with basic hygiene regulations during pregnancy.

Adolescent↗
PubMed1998

[Malaria in the southern sanitary district of Dakar (Senegal). 2. Entomologic data].

To complete a parasitological survey, entomological prospections were carried out in the southern sanitary District of Dakar, the most urbanized of the city and which includes the city centre and the oldest administrative districts. The prospections took place between June 1994 and May 1995 in sites 1.5 km apart, and distributed in such a manner that they covered the entire area. On a monthly basis, female Culicidae were collected in each site at night on human volunteers, followed the next day by the collection of early morning residual fauna in 10 bedrooms located in district concessions. For a total of 308 collections at night on human volunteers and from 1,510 rooms for the residual fauna, 22,901 female Culicidae were caught of which 167 anopheles, corresponding to 0.7%, the remaining 98.5% being Culex quinquefasciatus. This was the species that thus explained the mosquito-nuisance of which the inhabitants of the southern District complained during the period of survey. The female anopheles collected belonged to 2 species, An. arabiensis for 97.6% of those caught and An. pharoensis for 2.4%. An. arabiensis were very slightly represented in the southern District with a density of aggressive females of 0.26 bite/man/night (B/M/N) and a density per room of 0.05 female. The aggressive populations appeared to be relatively important only at the end of the rainy season (September-October) with an average of 0.65 B/M/N in sites located at the periphery of the district with a maximum of 1.33 B/M/N. The highest density of endophilic females registered at the end of the rainy season was 0.1 and its highest value in a given site was 0.36 female/room. The parturity rate of aggressive females was 43.5% and those collected in houses of 84% with an anthropophilic index of 0.98. None of the dissected An. arabiensis females (77.3% of those collected) was a carrier of Plasmodium sporozoites and the circum-sporozoite antigen was not found. A very weak density of An. arabiensis and absence of plasmodial infection among dissected females favoured the absence of malarial transmission in the southern District for the period considered. However malaria transmission could not be absolutely ruled out given the presence of hematozoa carriers, as was revealed by the longitudinal follow-up of a cohort carried out concurrently with the entomological prospections of whom some were residents having declared permanent residence in the city for over two years. This entomological data explain the results of the afore mentioned parasitological survey which, with a registered plasmodic index of 0.3%, means that the southern District can be considered as non endemic. The area is however exposed to the risk of epidemic malaria following an important proliferation of anopheles, which is always possible after heavy rains and flooding and/or an important immigration of persons coming from regions of high malarial endemicity.

Animals↗
PubMed1998

[Evaluation of parasitic risks for the population bordering on the Mbeubeuss public waste disposal, Dakar].

The authors carried out a parasitologic survey on 367 inhabitants of Malika, a village located in the immediate surroundings of M'Beubeuss disposal, as well as on 433 other residents of Keur Massar, a location 2 km farther, in order to assess parasitic hazards encountered by people neighbouring this disposal. As far as intestinal parasitosis are concerned, the prevalence rate was significantly higher in Malika (61.3%) than in Keur Massar (48.5%) The sex, social and economic status, level of education as well as the time of dwelling in the neighbouring area were identified as the risk factors of intestinal parasitism. Only the last one can be considered as significantly and independently related to a risk of intestinal parasitism. As for malaria, the plasmodial index in Malika was 6% versus 7.6% in Keur Massar (no significant difference). Thus, if it does exist for neighbouring people, an infestation risk by intestinal parasites related to exposure duration, contrarily, it does not exist for malaria. Appropriate steps should be taken to prevent the hazards encountered by inhabitants of surrounding villages.

Adolescent↗
PubMed1998

[Endemic parasitoses in the villages surrounding the Saloum fossil valley, Senegal].

In order to determine the prevalence rates of malaria, urinary schistosomiasis and intestinal parasitosis in Saloum's valley, the authors carried out a study which took place from november 16 to november 24, 1996. For malaria, the global parasites index was 22% (146/662). Malaria prevails at a hypoendemic level in N'Diobène and N'Guent-paté villages and at a medium-endemic level in Ribo-Escale and N'Dodj. The infestation index for urinary schistosomiasis was 8.9% (137/154) About intestinal parasite, among 868 persons screened, 124 showed one or several parasites, that is an infestation index of 14.3%. Appropriate steps should be taken to prevent an extension of these conditions along the fossil Saloum's valley.

Adolescent↗
PubMed1998

[Establishing a strain of Anopheles arabiensis (Diptera:Culicidae) in an insectarium].

For the first time in Dakar (Senegal), we managed to establish a local colony of Anopheles arabiensis (Diptera: Culicidae) in insectarium. The observations on the productivity of the colony showed a gradual adaptation of the preimaginal stages to insectarium conditions. The estimated duration of the development of the various preimaginal stages showed an interval of 24 hours for egg hatching, 48 h for stage I, 24 h for stage II, 24 h for stage III and 36 h for the pupal stage. Stage IV which makes the difference in the duration of the adult-egg cycle, varied from 1 to 13 days. Pupal moulting occurred mainly between 11 h and 19 h, with a peak between 14 h and 15 h. The duration of the preimaginal cycle in insectarium was from 8 to 11 days. This fits with the duration shown in natural breeding places during the rainy season (the best period for the development) which was from 9.5 to 13.3 days. Emergence, faster in males, occurred in the evening around 6.30-7 p.m. The emergence rate was higher in insectarium (92.9%) compared with that shown in the field (6 to 20%) (the natural breeding places are subject to biological and biochemical variations and to predators's action). The sex-ratio is equal to 1. The studies in insectarium showed that the gonotrophic cycle is 3 days in neonate blood fed after day 2 and also in parous ones. This cycle is 5 days in nulliparous with pregravid stage. The average longevity is 16 days with a maximum of 26 days in females and 43 days in males.

Animals↗
PubMed1998

[Obstetric complications of the first trimester in Western Africa].

The obstetrical complications affecting women in Benin, Senegal and Ivory Coast during the first trimester of pregnancy were studied. Information about the 345 women included in the study was collected from registers maintained by the eight participating maternity units. The most frequent complications observed were spontaneous abortions (50% of admissions), complications of induced abortions (34%), and ectopic pregnancy (8%). Overall, the patients appear to have gained rapid access to care: two thirds of the women underwent interventions on the day of admission. Nevertheless, there were three maternal deaths, two of which followed induced abortion complications.

Abortion, Induced↗
PubMed1997

Indoor resting by outdoor biting females of Anopheles gambiae complex (Diptera:Culicidae) in the Sahel of northern Senegal.

Three villages in the Senegal River basin were selected to study the biting and resting behavior of Anopheles gambiae s.l. in relation to human habits, rainfalls, and rice culture irrigation. All inhabitants sleep outside throughout the year, mainly under poor quality bednets. Mosquitoes were collected host-seeking during the night on human bait outside and resting during the day inside and outside in pit shelters. An. gambiae s.s. and An. arabiensis fed mainly outside, the only place where hosts are available; fed and gravid females resting indoors fed outside. The proportions of An. gambiae s.s. and An. arabiensis in outdoor biting catches and in indoor spray catches were not significantly different, but they differed from year to year with the latter sampling method, An. gambiae s.s. predominated in 1990, a more wet and humid year, whereas An. arabiensis was more common in 1991, which was an arid year. Both species are highly endophilic in this arid area where outdoor-resting places are limited.

Animals↗
PubMed1997

[The role of Hühner's direct post-coital test in the evaluation of conjugal sterility in the African environment in Senegal. (Apropos of 2593 post-coital tests performed by the clinical cytology, cytogenetic and reproduction biology laboratory at the University Hospital Center in Dakar, Senegal) 1983-1993].

About 2593 post-coïtal tests (PCT) or Hühner direct tests were realised in the laboratory of clinical cytology, cytogenetics and reproductive biology of the University medical Centre of Dakar, Senegal from 1983 to 1993. Analysing the results, the authors showed the importance of the infectious factor in women and also the role of male deficiency in conjugal sterility in black African environment. These realities have been confirmed cytospermiologic test deficient results. These sperm exams have shown among other things, the prevailing number of azoospermia (25%) and of oligo-asthénotératozoospermia (44%) in husbands of sterile women in the black African environment of Senegal. Pap's Tests have been jointly realised at the same time as 1902 PCT. The results have enabled us to track down 120 cervix with precancerous and cancerous cell alterations; 81 condylomas (HPV), 25 CIN1, 11 CIN2 and 3 CIN3 (CIN: cervical intra-epithelial Neoplasia). These facts suggest a cautious technics, and a prudent interpretation of the results and taking into account the competence and the subjectivity of the practitioner. We have learnt from the study that we must give as much as possible to biologists of Reproduction in southern countries, where conjugal sterility and cervix precancerous and cancerous cell alterations are high, a polyvalent training so that they can practise jointly the post-coïtal or Hühner direct test (PCT) and the Papanicolaou Colpocytologic Test (TP), provided that one owes a microscope.

Adolescent↗