[Malaria morbidity in Barkedji, village of Ferlo, in Senegal Sahelian area]. / Morbidité palustre 'a Barkedji, village du Ferlo, en zone sahélienne du Sénégal.

A study of malaria morbidity was carried out from November 1994 to October 1995, in a Ferlo village (Barkedji) characterized by a long persistence of the temporary ponds. The objective was to evaluate the repercussions of the strong and long anopheles transmission in humans. A clinical follow-up of a group of residents was conducted at home every 10 days by an investigator trained for taking axillary temperature and making thick smears, when suspecting malaria. Were included in the group, 123 voluntary subjects among whom 50% were children under 10 years old. Any feverish subject (T degree >37 degrees 5) or subject presenting other malaria symptoms (headaches, hot body shivers, sweats, aches...) was regarded as having a malaria attack as well as a parasitemia >2500 P/mm3 in children aged of 0 to 14 years old and 1000 P/mm3 in the oldest. During the study subjects with at least one feverish access, plasmodium infection and malaria attack were 58%, 33% and 22%, respectively. On 172 hyperthermias observed, 49% were accompanied by a circulating parasitemia and 30% corresponded to malaria attack. The feverish subjects (74% vs. 42%), the subjects with parasitemia (51% vs. 16%) and the cases of malaria (34% vs. 10%) were more frequently encountered in children under10 than in the oldest. The cases of malaria attacks were more frequent from November to January (70%). The strong intensity of malaria transmission in Barkedji and the persistence of its temporary ponds until January were sufficient to influence the level of malaria morbidity and consequently the development of an anti-malaria immunity by the indigenous population.

Human papillomavirus infection of the cervix uteri in women attending a Health Examination Center of the French social security.

Since human papillomavirus (HPV) is the central causal factor in cervical cancer, understanding the epidemiology of this infection constitutes an important step towards development of strategies for prevention. Six hundred and fifty seven cervical samples were tested for HPV using PCR with consensus primers (MY09/MY11), by genotyping (restriction and sequencing analyses) and by cervical cytology, from women who attended a Health Examination Center of the French social security. Women with no cervical smear as well as women with cytological abnormalities within the last 3 years were recruited. HPV DNA was detected in 7.3% of the women (5.3% for high-risk, 2.4% for low-risk, and 0.5% for unknown risk types) including 6 (0.9%) mixed infections. Fifteen different genotypes were detected, of which genotypes 16 (22.2%), 58 (13.0%), 18 (11.1%), 30 (9.2%), and 33 (9.2%) were the most prevalent. In age group 17-25 years, we found the highest frequencies for both any (22.1%) and high-risk (14.7%) HPV, and prevalences gradually decreased with age. 5.2% of low-grade squamous intraepithelial lesion, 0.3% of high-grade squamous intraepithelial lesion, and 1.2% of atypical squamous cells of undetermined significance were found. The frequencies of high risk and all HPV types were significantly higher in squamous intraepithelial lesions than in those with normal and reactive/reparative changes (P < 0.0001). The prevalence of high-risk HPV in the atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion group (28.6%) was significantly higher than in the normal and reactive/reparative changes groups (3.4%) (P < 0.0001). HPV detection was associated with younger age, single marital and non-pregnant status (P < 0.0001), premenopausal status (P = 0.0004), and contraception (P = 0.0008). Marital status (OR 4.5; 95% CI = 2.3-9.0) and tobacco consumption (OR 3.0; 95% CI = 1.6-5.7) were predictive independent factors of HPV infection. The French system of Health Examination Centers might be of interest for following women regularly, especially those with a low socioeconomic status.

Evolutionary relationship between Old World West Nile virus strains. Evidence for viral gene flow between Africa, the Middle East, and Europe.

Little is known about the genetic relationships between European and other Old-World strains of West Nile virus (WNV) and persistence of WNV North of Mediterranean. We characterized the complete genomes of three WNV strains from France (horse-2000), Tunisia (human-1997) and Kenya (mosquito-1998), and the envelope, NS3 and NS5 genes of the Koutango virus. Phylogenetic analyses including all available full-length sequences showed that: (1) Koutango virus is a distant variant of WNV; (2) the three characterized strains belong to lineage 1, clade 1a; (3) the Tunisian strain roots the lineage of viruses introduced in North America. We established that currently available partial envelope sequences do not generate reliable phylogenies. Accordingly, establishing a large WNV sequence database is pivotal for the understanding of spatial and temporal epidemiology of this virus. For rapid completion of that purpose, colinearized E-NS3-NS5 gene sequences were shown to constitute a valuable surrogate for complete sequences.

Removal of the organic surface layer in combined sewer sediment using a flushing gate.

Recent research identified the different sources of pollution of wet weather Combined Sewers Overflows (CSOs): it appeared that the deposits in sewers, and especially an organic layer situated at the water-sediment interface, may contribute 40-70% to the total pollution load of CSOs. Using the cyclic flush Hydrass gate, we generated increased water flows during dry weather. The effects of flushing the deposits have been analysed: the eroded particles sampled during the first flush wave show pollutant characteristics similar to characteristics measured in the organic layer. The organic layer that has formed on the surface of deposits can thus be washed off before rainstorms occur using the cyclic flushing technique.

Persistence of Anopheles arabiensis during the severe dry season conditions in Senegal: an indirect approach using microsatellite loci.

Variation at nine microsatellite loci was investigated to understand how Anopheles arabiensis populations survive the dry season in the sahelian region of Senegal. Low estimates of genetic differentiation (F(ST) = 0.012, R(ST) = 0.009) between two populations, 250 km apart, suggested extensive gene flow across this distance. Despite extreme seasonal fluctuation in abundance with dry season minima in which mosquitoes virtually disappeared, allele frequencies remained stable over time in the village of Barkedji from August 1994 to December 1997 (including four rainy seasons and three dry seasons). The effective population size (Ne) was estimated to be 601 with 95% CI (281, 1592), providing strong evidence against annual bottlenecks. Differences in measures of genetic diversity and linkage disequilibrium between the dry and the rainy seasons were not detected. These results suggest that despite extreme minima in local density, An. arabiensis maintains large permanent deme spread out over large area.

Comparison of behavior and vector efficiency of Anopheles gambiae and An. arabiensis (Diptera:Culicidae) in Barkedji, a Sahelian area of Senegal.

The ecology, population dynamics, and malaria vector efficiency of Anopheles gambiae and An. arabiensis were studied for 2 yr in a Sahelian village of Senegal. Anophelines were captured at human bait and resting indoors by pyrethrum spray. Mosquitoes belonging to the An. gambiae complex were identified by polymerase chain reaction. Of 26,973 females, An. arabiensis represented 79% of the mosquitoes captured and remained in the study area longer than An. gambiae after the rains terminated. There were no differences in nocturnal biting cycles or endophagous rates between An. gambiae and An. arabiensis. Based on an enzyme-linked immunosorbent assay test of bloodmeals, the anthropophilic rate of these 2 vectors were both approximately 60%, when comparisons were made during the same period. Overall, 18% of the resting females had patent mixed bloodmeals, mainly human-bovine. The parity rates of An. gambiae and An. arabiensis varied temporally. Despite similar behavior, the Plasmodium falciparum circumsporozoite protein (CSP) rates were different between An. gambiae (4.1%) and An. arabiensis (1.3%). P. malariae and P. ovale only represented 4% of the total Plasmodium identified in mosquitoes. Transmission was seasonal, occurring mainly during 4 mo. The CSP entomological inoculation rates were 128 bites per human per year for the 1st yr and 100 for the 2nd yr. Because of the combination of a high human biting rate and a low CSP rate, An. arabiensis accounted for 63% of transmission. Possible origin of differences in CSP rate between An. gambiae and An. arabiensis is discussed in relation to the parity rate, blood feeding frequency, and the hypothesis of genetic factors.

High annual and seasonal variations in malaria transmission by anophelines and vector species composition in Dielmo, a holoendemic area in Senegal.

We conducted a three-year entomologic study in Dielmo, a village of 250 inhabitants in a holoendemic area for malaria in Senegal. Anophelines were captured on human bait and by pyrethrum spray collections. The mosquitoes belonging to the Anopheles gambiae complex were identified using the polymerase chain reaction. Malaria vectors captured were An. funestus, An. arabiensis, and An. gambiae. Anopheles funestus was the most abundant mosquito captured the first year, An. arabiensis in the following years. The annual entomologic inoculation rates calculated by enzyme-linked immunosorbent assay were 238, 89, and 150 for the first, second, and third years, respectively. Each year there was a peak of transmission at the end of the rainy season, but transmission occurred year round. The heterogeneity of transmission was found at four different levels: 1) the relative vector proportion according to the place and method of capture, 2) the human biting rate and relative proportion of vectors by month and year, 3) the infection rate of each vector by year, and 4) the number of infected bites for all vectors, and for each species, for the year. Our data show that even in areas of intense and perennial transmission, there exist large longitudinal variations and strong heterogeneity in entomologic parameters of malaria transmission. It is important to take these into account for the study of the variations in clinical and biological parameters of human malaria, and to evaluate this relationship, a very thorough investigation of transmission is necessary.

Four years' entomological study of the transmission of seasonal malaria in Senegal and the bionomics of Anopheles gambiae and A. arabiensis.

From 1993 to 1996, an entomological survey was conducted in the village of Ndiop, Senegal, as part of a research programme on malaria epidemiology and the mechanisms of protective immunity. Mosquitoes were captured on human bait and by indoor spraying. Species from the Anopheles gambiae complex were identified using the polymerase chain reaction, and Plasmodium falciparum infections were detected by enzyme-linked immunosorbent assay for circumsporozoite protein. The vector species identified were A. gambiae (33.9%), A. arabiensis (63.2%), A. melas (0.3%) and A. funestus (2.5%). Similar proportions of A. gambiae (74.2%) and A. arabiensis (73.8%) contained human blood; 27.0% of A. gambiae and 28.3% of A. arabiensis had fed on cattle. The sporozoite rates were similar for A. gambiae (3.2%) and A. arabiensis (3.7%). The annual entomological inoculation rates varied greatly depending on the year. There were 63, 17, 37 and 7 infected bites per person per year in 1993, 1994, 1995 and 1996 respectively. Transmission was highly seasonal, from July to October. A. arabiensis was responsible for 66% of malaria transmission, A. gambiae for 31%, and A. funestus for 3%.

[Evaluation of a clinical course in an oncology department during the second cycle of medical education. A 12-year study by questionnaire among 321 students]. / Evaluation d'un stage hospitalier en cancérologie au cours du deuxième cycle des études médcales. Enquête par questionnaire chez 321 étudiants en 12 ans.

The comprehensive cancer center in the Southwest of France, Bergonié Institute hosts medical students in 4th-6th year of their studies, for 4-month courses. This course was evaluated at its end by a questionnaire, during two periods of 6 years: 1983-88. 161 students; 1990-95, 160 students. Due to the policy of the Bordeaux University, these students were significantly younger during the second period: 48.4% in 4th year vs 25.8% in the first period (P = 0.00024). The main reasons for choosing this hospital were to meet cancer patients (54.8%), to improve knowledge in oncology (49.7%) or to see a variety of diseases, unlike in other specialty services (20.8%). At the end of the course, the main investigation in oncology appeared to be pathology (40.8%), radiology (38.2%) or blood cell counts (14.5%). Their training was highly (2+) or very highly (3+) rated by 67.9% of the students in theoretical matters, by 66% in clinical practice and by 92.5% in behavior. The best-learned fields were relations with patients (67.4%), treatments (24.5%) and clinical examination (23.5%). Students declare to have been negatively impressed by failures and deaths (34.7%), patients in poor condition (24.7%) or treatments poorly tolerated or not efficient enough (12.2%). They declare to have been well impressed by cooperation of caregivers (26.5%), comprehensive care (22.7%), teachers' efforts (22.1%), patient-caregiver relations (21.%) and courageous patients (18.1%). Finally students' presence during consultation is useful to see outpatients in good condition or cured patients. Between the first and the second period, there is a significant decrease of clinical training and a trend in favor of improved treatment and better prognosis. Thus this hospital appears mainly useful for training in patient-doctor relations and in clinical practice in a variety of diseases. Efforts have to be made to further improve clinical training. Such an investigation should be pursued to check the students' training periodically. This will allow the adaptation and improvement of the teaching, in accordance with changes in patients' conditions and treatments.

[The utilization of molecular biological tools in the study of malaria transmission: example of programs conducted in Senegal]. / Intérêt de l'utilisation des outils de biologie moléculaire dans l'étude de la transmission du paludisme: l'exemple des programmes conduits au Sénégal.

Some informations about malaria transmission, which has until nox difficult to get, can be obtained thanks to the use of molecular biology tools, PCR mainly. In Senegal, we use that technique to solve two kinds of problems: -Identification of species of the Anopheles gambiae complex: PCR technique is useful compared to other diagnostic methods (chromosome pattern, DNA probes, etc.) because it enables quickly and simply identification of captured anopheles from the DNA contained in their legs. The rest of the mosquito is tested by circumsporozoite protein antigen ELISA and blood meal ELISA. The data obtained are used to determine distribution, cycles, trophic preferences and comparative vectorial capacities of Anopheles gambiae, Anopheles arabiensis and Anopheles melas. -Identification in a mosquito blood meal of the individual bitten: we propose to evaluate factors (weight, age, sex, location of bedroom, etc.) which could explain why individuals are more, or less, bitten by a Plasmodium vector. Genetic typing is used on inhabitants'leukocytes DNA and on the leukocyte DNA extracted from the blood meal of resting anopheles. Through the high degree of polymorphism of three (AAAG)n microsatellites markers, we hope, using PCR, to attribute each blood meal to one individual. Statistical analysis will be used to identify attractivity factors and to determine more precisely the inoculation rates for each group rather than the classical rate calculated with male adults volunteers.

[Perception of cancer by general practitioners. Development over 15 years]. / Perception du cancer chez les médecins généralistes. Evolution sur 15 ans.

Fifteen years after two surveys among general practitioners in the Southwest of France, concerning their attitudes towards cancer patients, a new survey was made using the same questions. In the spring of 1991, 731 general practitioners in Gironde were asked by a written questionnaire sent by mail: 261 answers (36%) forming a fair sample, were analyzed. Though incidence of cancer in physician's practice is low, these patients represent an important burden. Difficulties in coping with these patients during relapse or at the end of life are mainly psychological in relation to the importance of moral burden and the time spent. These psychological difficulties have increased during the past 15 years whereas technical medical problems have decreased. According to 80% general practitioners, cancer patients know their diagnosis. This knowledge is independent of practitioner's age and the working place, and it does not alter the difficulties for practitioner.

[Use of a heterologous antigen (Schistosoma bovis) for the immunoenzymatic serodiagnosis of urinary bilharziasis]. / Utilisation d'un antigène hétérologue (Schistosoma bovis) pour le sérodiagnostic immunoenzymatique de la bilharziose urinaire.

The authors propose the utilisation of an heterologous antigen, Schistosoma bovis for the diagnosis of human schistosomiases by enzyme immunoassay. The method is particularly recommended for the detection of S. haematobium and S. intercalatum diseases. It is sensitive and reproducible, its specificity being only limited by the existence of cross-reactions with some tissular helminthiases.