Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Senegal”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Distribution of RNA coliphages in Senegal, Ghana, and Madagascar.

The distribution patterns of RNA coliphages (phages) in Senegal, Ghana, and Madagascar were investigated by collecting sewage samples from domestic drainage in November, 1980. In Senegal, among 65 sewage samples collected mainly from Dakar and its vicinity, 14 (22%) contained RNA phages (16 strains). By serological analysis, 13 of 16 strains were found to belong to group III. This is consistent with the distribution pattern of RNA coliphages in tropical and subtropical regions of Asia. In Ghana, however, among 106 samples collected from Accra, Suhum, and their vicinities, only seven (7%) contained RNA phages (seven strains) (groups I, II, and III [1:3:3]). In Madagascar, among 124 samples collected from Antananarivo, Moramanga, and their vicinities, seven (6%) contained RNA phages (seven strains) (groups I, II, III, and IV [1:1:1:4]). In spite of the low isolation frequency, it can be said that Madagascar appears to have a unique distribution pattern (abundance of group IV phages) which differs from that of any other countries we have examined. The generality of the distribution pattern of RNA phages in the tropical region (abundance of group III phages) was thus verified at least in Senegal.

Coliphages↗

Genetic diversity of KIR natural killer cell markers in populations from France, Guadeloupe, Finland, Senegal and Réunion.

Killer cell immunoglobulin-like receptors (KIRs) belong to a diverse family of natural killer (NK) cell receptors recognizing human leukocyte antigen (HLA) class I molecules. Due to this functional link, KIR molecules are expected to display a high polymorphism, such as their HLA ligands. Moreover, many studies conducted in mouse and human models have shown that NK-KIR receptors play an important role in haematopoietic stem cell transplantation (HSCT). A beneficial impact of peculiar KIR ligand (HLA) mismatching has been reported suggesting a role to this combinatory HLA-KIR polymorphism. It is thus important to investigate KIR diversity in various human populations. To this end, we used polymerase chain reaction-sequence-specific primers to evaluate KIR gene in five selected populations (France, Guadeloupe, Senegal, Finland and Réunion). Genotypic and haplotypic frequencies were computed, as well as genetic distances and dendrogram (phylip package). These data illustrate the genetic relationship of these five populations through the KIR polymorphism. Results revealed a wide diversity in KIR gene frequencies in Guadeloupe and Réunion, and a high specificity in Senegal. The obtained dendrogram indicated small genetic distances between France, Guadeloupe and Réunion as well as between France and Finland. Senegal showed a distant genetic relationship with the other countries and, interestingly, an inverted ratio of coding/non-coding (KIR2DS4/1D) alleles compared with Caucasians. These data expose the broad diversity in KIR genes worldwide and show that KIR genes are pertinent tools in human population genetics. If the role of KIR donor-recipient incompatibilities is confirmed, KIR diversity according to ethnicity should be taken into account during the selection of HSCT donors.

Alleles↗

The 1998 Senegal epidemic of meningitis was due to the clonal expansion of A:4:P1.9, clone III-1, sequence type 5 Neisseria meningitidis strains.

Between January and April 1998, a meningitis outbreak due to serogroup A meningococcus took place in Senegal. The outbreak began in Gandiaye, 165 km to the east of Dakar, and progressed towards the towns of Gossas, Niakkhar, Guinguineo, Fatik, Foundiougne, Dioffior, Sokone, Kaolack, and Nioro. At the same time, the outbreak reached regions of Kaffrine, Koungheul, and Tambacounda in the east of Senegal. A total of 1,350 cases and 200 deaths were reported. The WHO Collaborating Center in Marseilles received 24 strains for analysis. All were serogroup A Neisseria meningitidis, type 4 and subtype P1.9. Multilocus enzyme electrophoresis, performed by Institut Pasteur Paris, showed that the strains belonged to clone III-1. DNA restriction fragments generated by endonuclease BglII and analyzed by pulsed-field gel electrophoresis showed 24 indistinguishable fingerprint patterns similar to those of meningococcus strains isolated from African outbreaks since 1988. Three strains were studied by multilocus sequence typing (MLST) with seven loci. The comparison between sequences and existing alleles on the MLST website () allowed us to assign these strains to sequence type 5 (ST5), as their sequences were identical to the consensus at seven loci. All 24 strains were susceptible to penicillin, amoxicillin, chloramphenicol, and rifampin. Subgroup III is finishing its spread towards west of the meningitis belt of Africa. To our knowledge, this is the first time subgroup III, and more precisely ST5, strains are reported as being responsible for a meningitis outbreak in Senegal.

Bacterial Typing Techniques↗

Molecular epidemiology of human immunodeficiency virus type 1 sub-subtype A3 in Senegal from 1988 to 2001.

The global human immunodeficiency virus (HIV)epidemic is characterized by significant genetic diversity in circulating viruses. We have recently characterized a group of viruses that form a distinct sub-subtype within the subtype A radiation, which we have designated HIV type 1 (HIV-1) sub-subtype A, circulating in West Africa. A prospective study of a cohort of female sex workers (FSW) in Dakar, Senegal over an 18-year period indicated that an A3-specific sequence in the C2-V3 region of the env gene was found in 46 HIV-1-infected women. HIV-1 sub-subtype A3 appeared in the FSW population as early as 1988 and continued to be transmitted as of 2001. We also found that HIV-1 A3 is not confined to the FSW cohort in Senegal but is also circulating in the general population in Dakar. Furthermore, analyses of viral sequences from a few other West and Central African countries also demonstrated evidence of HIV-1 A3 sequence in isolates from HIV-1-infected people in Ivory Coast, Nigeria, Niger, Guinea Bissau, Benin, and Equatorial Guinea. Overall, because of the evidence of sub-subtype A3 in the general population in Senegal, as well as in a few neighboring West and Central African countries, along with the increasing incidence of infection with A3-containing viruses in the Dakar high-risk FSW population, we feel that HIV-1 sub-subtype A3 viruses are important to distinguish and monitor.

Base Sequence↗

Clinical carbapenem-resistant Enterobacterales in a University Hospital in Dakar, Senegal: genomic insights into Enterobacter hormaechei ST182 strains carrying blaNDM-5 and blaOXA-48 genes .

Senegal has witnessed the emergence and spread of carbapenem-resistant Enterobacterales (CRE), which often cause deadly infections. Accordingly, this study aimed to determine the antimicrobial susceptibility and prevalence of carbapenemases, as well as to perform a whole-genome sequence analysis of clinical CRE isolates from a university hospital in Dakar, Senegal. MALDI-TOF MS and VITEK2 systems were used for bacterial identification and antimicrobial susceptibility testing (AST). Carbapenemase- and cephalosporinase-encoding genes were screened using simplex end-point polymerase chain reaction. Whole-genome sequencing (WGS) was performed using the Illumina MiSeq platform. The CRE isolates were resistant to almost all the 34 antimicrobials tested. Nevertheless, colistin and amikacin remained active, with susceptibility rates of 96% and 71%, respectively. Only the carbapenemase genes blaOXA-48 (53.8%; 15/28) and blaNDM (35.7%; 10/28) and the cephalosporinase gene blaCMY-1 (25%; 7/28) were identified. In this context, two extensively drug-resistant Enterobacter hormaechei isolates were subjected to WGS analysis. These isolates were assigned as sequence type (ST) 182 and carried several genes related to antimicrobial resistance (AMR), metal tolerance, and virulence. An IncL/M plasmid with 61,054 bp in length was identified as carrying the blaOXA-48 gene, whereas an IncFIB(pECLA)/IncFII(pECLA)/IncX3 mutireplicon plasmid with 217,745 bp in length was detected as harboring the blaNDM-5 gene and other genes related to AMR and metal tolerance. Our study presents the first landscape of clinical CRE circulating in Senegal, along with additional genomic analysis of E. hormaechei ST182 strains, which could be useful for mitigating the burden associated with CRE in this country.IMPORTANCEThe investigation of global critical priority CRE isolates has become crucial to reduce morbidity and mortality associated with AMR. This study revealed that colistin and amikacin can be considered good alternatives for treating CRE-associated infections in Dakar. In addition, the genomic approach revealed that the CRE isolates carried both a wide resistome and virulome. Moreover, the abundance of horizontal gene transfer regions in the genomes suggests the great implications of mobile genetic elements in the spread of AMR in Dakar. Furthermore, this study reported the complete sequences of chromosomes and blaOXA-48 and blaNDM-5-carrying plasmids. Our findings are of great importance because complete genome sequences are still rarely characterized in the West African region. Finally, this study highlights the importance of strengthening genomic surveillance of CRE in sub-Saharan African countries to mitigate the burden associated with these pathogens.

Senegal↗

Implication of Bulinus truncatus in the transmission of urinary schistosomiasis in Senegal, West Africa.

Studies on the compatibility between Bulinus truncatus and Schistosoma haematobium from various areas in the Senegal River basin (SRB) were carried out, to investigate the role of B. truncatus in the epidemiology of urinary schistosomiasis in Senegal. The results show that B. truncatus from the Lower Valley is not compatible with S. haematobium from the Middle Valley. Interestingly, the study reveals that B. truncatus from the Upper Valley is compatible with S. haematobium from the same area, and that S. haematobium from the Middle Valley is compatible with B. truncatus from the Lower Valley. Bulinus truncatus naturally infected with S. haematobium have been collected from the Upper Valley of the SRB. These results indicate that B. truncatus is involved in the urinary schistosomiasis in Senegal.

Animals↗

Water-related disease patterns before and after the construction of the Diama dam in northern Senegal.

The ecological changes caused by projects for the development of water resources are known to affect the epidemiology of water-related diseases. The effects of the construction of the Diama dam (completed in 1986) in the Senegal River on the epidemiology of malaria, urinary and intestinal schistosomiasis, diarrhoea and dysentery were investigated in four districts in northern Senegal. To make allowance for any general trend in reported morbidity (caused by changes in demography or the healthcare system), the numbers of cases of these illnesses reported by the basic healthcare facilities before and after the completion of the dam were compared with those of respiratory disease. Prior to the construction of the dam, malaria was the most encountered water-related disease in the medical records of all districts, followed by diarrhoea, dysentery and urinary schistosomiasis. This order remained the same after the completion of the dam. Despite the optimism of health-assessment reports prepared prior to the construction of the Diama dam, the unexpected appearance and spread of intestinal schistosomiasis as well as an increase in the incidence of urinary schistosomiasis have aggravated public health in the Senegal River basin. It remains to be judged whether the economic benefits of the dam will counterbalance its adverse effects.

Diarrhea↗

Treponemal infection rates, risk factors and pregnancy outcome in a rural area of Senegal.

A rural population of east Senegal has been under demographic surveillance for more than 30 years and a high rate of infertility has been reported. The aim of the study is to describe HIV and treponemal infection epidemiology and association with outcome of pregnancy in a population of rural Senegal. A population-based cross-sectional study was conducted among 952 randomly-selected adults of a rural community of Senegal. No participant was found to be infected with HIV, 11% had evidence of past syphilis and 5% of active syphilis. Active syphilis was associated among men with age, long-term mobility and having partners in an urban area in the last 12 months and among women with being divorced or widowed. No association was found between past or active syphilis and abortion or stillbirth but women aged 40 and more with past or active syphilis were significantly more likely to have had no history of gestation than women with no evidence of syphilis infection. In conclusion our results call for more research to understand the epidemiology of treponemal infection and to elucidate types of Treponema pallidum involved.

Female↗

Amplification of the sylvatic cycle of dengue virus type 2, Senegal, 1999-2000: entomologic findings and epidemiologic considerations.

After 8 years of silence, dengue virus serotype 2 (DENV-2) reemerged in southeastern Senegal in 1999. Sixty-four DENV-2 strains were isolated in 1999 and 9 strains in 2000 from mosquitoes captured in the forest gallery and surrounding villages. Isolates were obtained from previously described vectors, Aedes furcifer, Ae. taylori, Ae. luteocephalus, and--for the first time in Senegal--from Ae. aegypti and Ae. vittatus. A retrospective analysis of sylvatic DENV-2 outbreaks in Senegal during the last 28 years of entomologic investigations shows that amplifications are periodic, with intervening, silent intervals of 5-8 years. No correlation was found between sylvatic DENV-2 emergence and rainfall amount. For sylvatic DENV-2 vectors, rainfall seems to particularly affect virus amplification that occurs at the end of the rainy season, from October to November. Data obtained from investigation of preimaginal (i.e., nonadult) mosquitoes suggest a secondary transmission cycle involving mosquitoes other than those identified previously as vectors.

Aedes↗

Arbovirus isolations from mosquitoes collected during 1988 in the Senegal River basin.

During August and September 1988, we collected adult mosquitoes from 14 locations in the Senegal River basin to search for evidence of Rift Valley fever (RVF) viral activity one year after the 1987 outbreak, which occurred along the Senegal-Mauritania border. More than 62,000 specimens representing 18 species in seven genera were collected with carbon dioxide-baited, solid-state Army miniature light traps and sheep-baited traps. Twenty virus isolations from Culex, Aedes, and Anopheles mosquitoes were recovered from six locations: Fanaye Diery (11), Bode (four), Matam (two), Diongui (one), Ndialene (one), and Ngoui (one). Species yielding viral isolates were Anopheles pharoensis (eight), Culex tritaeniorhynchus (three), Cx. univitattus gr. (three), Cx. antennatus (two), Cx. poicillipes (two), Ae. hirsutus (one), and An. gambiae (one). Viruses were identified by complement fixation, and virus and plaque-reduction neutralization testing as Ngari (Bunyavirus, Bunyaviridae) (n = 15), Babanki (Alphavirus, Togaviridae) (n = 3), Bagaza (Flavivirus, Flaviviridae) (n = 1), and Bangui (Bunyavirus-like) (n = 1). No evidence of any RVF viral activity in the Senegal River Basin was detected in the mosquitoes tested.

Animals↗

Vectors of Chikungunya virus in Senegal: current data and transmission cycles.

Chikungunya fever is a viral disease transmitted to human beings by Aedes genus mosquitoes. From 1972 to 1986 in Kédougou, Senegal, 178 Chikungunya virus strains were isolated from gallery forest mosquitoes, with most of them isolated from Ae. furcifer-taylori (129 strains), Ae. luteocephalus (27 strains), and Ae. dalzieli (12 strains). The characteristics of the sylvatic transmission cycle are a circulation periodicity with silent intervals that last approximately three years. Few epidemics of this disease have been reported in Senegal. The most recent one occurred in 1996 in Kaffrine where two Chikungunya virus strains were isolated from Ae. aegypti. The retrospective analysis of viral isolates from mosquitoes, wild vertebrates, and humans allowed to us to characterize Chikungunya virus transmission cycles in Senegal and to compare them with those of yellow fever virus.

Aedes↗

[Adults with sickle cell anemia in Senegal. Clinical study of 40 homozygote subjects].

While the well-documented life expectancy of patients with homozygous sickle cell anemia (SS) is 40 years in industrialized countries, this question remains unanswered in black Africa. The purpose of this prospective study was to establish the clinical phenotype for Senegal. A severity score based on 12 clinical, laboratory, radiological, and prognostic findings was calculated and correlated with age and hemoglobin F level. A total of 40 SS homozygotes over 15 years of age (mean age: 25 years) were hospitalized between January 1996 and January 1998 at the Principal Hospital in Dakar. The most common events requiring hospitalization were vasoocclusive phenomena (n = 26) but the incidence of these complications declined significantly with age (p < 0.05). The mean hemoglobin level was 4.4 mmol/l and the mean hemoglobin F level was 6.2 p. 100. The incidence of visceral involvement was low (lithiasic vesicules in 17 cases, necrosis of the head of the femur in 7, and abnormal cardiac ultrasound findings in 10). Only one patient died during the study. No correlation was found between severity score and either age or hemoglobin F level. These findings confirm that the phenotype is less severe in Senegal. However they also show that organ damage is common by the time that patients reach adulthood and thus underline the need for prevention and education to improve survival of SS homozygotes in Senegal.

Adolescent↗

[Characterization of entomopathogenic Bacillus samples isolated in Senegal and study of their toxicity for malaria vectors].

A screening program developed in Senegal to isolate new strains of entomopathogenic Bacillus has led to the isolation of 194 strains of Bacillus thuringiensis and 9 strains of Bacillus sphaericus from various sites and insect samples. The characterization of these strains regarding their H serotype, their crystal composition and their toxicity against mosquitoes (Culex pipiens, Aedes aegypti and Anopheles stephensi) has led to the isolation of 27 mosquitocidal strains. As malaria is an important public health problem in Senegal, these strains were more completely characterized looking for their toxicity against the two major malaria vectors in Senegal: Anopheles gambiae and Anopheles arabiensis.

Animals↗

[Regulations on tuberculosis risk in workplaces in Senegal].

National immunization and control programs have not brought about a significant decline in tuberculosis, which remains a real public health concern in our regions. Prevention in the working environment should be part of an overall prevention program for the general population. Nevertheless, companies should play a leading role because they have the necessary structure and assets. We analyzed the epidemiology of tuberculosis in the working environment using demographic data on employees in Senegal, current medicolegal data on tuberculosis in Senegal and data on prevention of tuberculosis. Our analysis led to a proposed strategy for controlling tuberculosis spread and its prevention in the working environment in Senegal.

Adult↗

How to reach clients of female sex workers: a survey by surprise in brothels in Dakar, Senegal.

OBJECTIVE: To describe the sampling techniques and survey procedures used in identifying male clients who frequent brothels to buy sexual services from female sex workers in Dakar, Senegal, with the aim of measuring the prevalence of human immunodeficiency virus (HIV) infection and investigating related risk behaviours. METHODS: Surveys were conducted in seven brothels in Dakar, Senegal. Clients were identified "by surprise" and interviewed and requested to donate saliva for HIV testing. RESULTS: Of the 1450 clients of prostitutes who were solicited to enter the study, 1140 (79.8%) agreed to be interviewed; 1083 (95%) of these clients provided saliva samples for testing. Of the samples tested, 47 were positive for HIV-1 or HIV-2, giving an HIV prevalence of 4.4%. CONCLUSION: The procedures adopted were successful in reaching the target population. Men present in the brothels could not deny being there, and it proved possible to explain the purpose of the study and to gain their confidence. Collection of saliva samples was shown to be an excellent method for performing HIV testing in difficult field conditions where it is hard to gain access to the population under study. The surveying of prostitution sites is recommended as a means of identifying core groups for HIV infection with a view to targeting education programmes more effectively. In countries such as Senegal, where the prevalence of HIV infection is still low, interventions among commercial sex workers and their clients may substantially delay the onset of a larger epidemic in the general population.

Contact Tracing↗

[Impact of algorithms on abusive prescriptions of parental drugs at the health post level in the Tambacounda health district, Senegal].

In order to increase the effectiveness and the efficiency of diagnosis and treatment procedures of the most common diseases, algorithmic pathways have been developed and applied within the implementation of the "Bamako Initiative Strategy" at the health post level in Senegal. Among the many expected advantages of these pathways, was a reduction of abusive prescriptions of parental drugs. A study comparing the trend of the prescriptions 2 years before (1991) and 2 years after (1996) the implementation of the Bamako Initiative strategy, was conducted using 810 randomly selected patients in 7 out of the 19 health posts of the Tambacounda Health district, one of the 45 health districts of Senegal. In 1991, all the oral drugs prescribed (sirup, pills, powder) represented 54.5% against 45.5% for parental drugs (intramuscular and intravenous drugs). These proportions had risen to respectively 78.1% and 21.9% in 1996. The difference thus observed is statistically significant with a khi2 test of 47.76 and p<10(-7). This result then suggests that the use of pathways had highly reduced the prescription of parental drugs among patients treated in the health posts of the Tambacounda health district in Senegal.

Adult↗

[Description of the first cases of serotype A, sequence type (ST)-11 meningococcal meningitis in Senegal].

Senegal is located in the African meningitis belt and meningococcal meniningitis outbreaks are yearly events. Occurrence of an epidemic involving serogroup W135 in 2000 and its spread following the Hajj (pilgrimage to Mecca) exposed the strongly Moslem population of Senegal to the risk of early infection. Indeed the first two cases in Dakar occurred simultaneously with the spread of this epidemic strain. The purpose of this article is to describe clinical, laboratory, and therapeutic findings in these two cases and the results of the ensuing epidemiological survey. The relationship with the pilgrimage and consequences on public health in Senegal are discussed.

Child, Preschool↗

[Appraisal of snakebite incidence in Senegal, West Africa].

Surveys were carried out in four savannah areas of Senegal. The studied zones had different climatic, economic and demographic characteristics. Two types of studies were performed: on the one hand, a retrospective survey carried out in health centres and, on the other, household surveys in the corresponding areas; all households were questioned in Niakhar, but only selected households in other areas following WHO method of cluster survey for vaccine coverage. Questions involved the circumstances of the bite, symptoms and treatment. The retrospective survey reported very few cases of snakebites over the prospected period. In addition, two zones of surveys were population study areas under observation since more than 20 years and, it has been possible to check certain information in the data base. In the first zone, Thies, a sub-urban area (population density higher than 150 inhabitants per km2), primarily occupied by fruit plantations (mangos, oranges, lemons) and gardens, the annual incidence of snakebites (i.e. all snakebites including those without any symptoms) reached 43 bites per 100,000 and mortality was 1.8 deaths per 100,000. In the study zone of Niakhar, located in the groundnut culture area of Senegal which is also highly populated (130 inhabitants per km2), the incidence of snakebites was 23 bites per 100,000 and mortality was close to 1.8 deaths per 100,000 a year. The area of Nioro du Rip is a mixed agricultural area (food producing and revenue agriculture) and less populated (100 inhabitants per km2). The annual incidence was roughly of 304 per 100,000 and the mortality 3.6 per 100,000. Finally, the fourth area, Bandafassi in the extreme South-East of Senegal is a mountainous zone exclusively occupied by bush and food producing agriculture, and sparsely populated (20 inhabitants per km2). The incidence was 915 per 100,000 and the mortality 11 deaths per 100,000. The population at risk involved males from 15 to 45 years. Pastoral work (agriculture and breeding) was at the origin of the majority of the accidents. The recourse to traditional practitioners was systematic, which explained why the data from the health centers were not relevant enough to evaluate the importance of the envenoming.

Adult↗