Seasonal variation of asymptomatic viral and bacterial nasopharyngeal carriage in rural Senegal.

BACKGROUND: The surveillance of respiratory pathogens in rural areas of West Africa has, to date, largely been focussed on symptoms. In this prospective study conducted prior to the COVID-19 pandemic, we aimed to assess the asymptomatic prevalence of respiratory pathogen carriage in a group of individuals living in a rural area of Senegalese. METHODS: Longitudinal follow up was performed through monthly nasopharyngeal swabbing during the dry season and weekly swabbing during the rainy season. We enrolled 15 individuals from the village of Ndiop. A total of 368 nasopharyngeal swabs were collected over a one-year period. We investigated the prevalence of 18 respiratory viruses and eight respiratory bacteria in different age groups using singleplex and multiplex PCR. RESULTS: In total, 19.56% of the samples (72/368) were positive for respiratory viruses and 13.60% of the samples (50/368) were positive for respiratory bacteria. Coronaviruses (19/72, 26.39%), adenoviruses (17/72, 23.61%), rhinoviruses (14/72, 19.44%), Streptococcus pneumoniae (17/50, 34%), and Moraxella catarrhalis (15/50, 30%) were the most frequently detected viruses. Interestingly, the carriage of respiratory pathogens was shown to be more frequent during the rainy season, as pluviometry was shown to be positively associated with the occurrence of respiratory viruses such as influenza (P = .0078, r2 =.523) and RSV (P = .0055, r2 =.554). CONCLUSIONS: Our results show a non-negligible circulation of respiratory pathogens in a rural area in Senegal (West Africa) with an underestimated proportion of asymptomatic individuals. This study highlights the fact that the circulation of viruses and bacteria in the community has been overlooked.

Influenza at the 2021 Grand Magal of Touba and possible spread to rural villages in South Senegal - a genomic epidemiological study.

OBJECTIVES: Influenza is frequent among pilgrims participating in the Grand Magal de Touba (GMT), in Senegal, with a potential to spread to contacts when they return home. METHODS: Ill pilgrims consulting at a health care center in Mbacké city close to Touba during the 2021 GMT, pilgrims returning to Dielmo and Ndiop villages, and patients who did not travel to Touba and consulted at health care centers in these two villages in 2021 were tested for the influenza virus by polymerase chain reaction on nasopharyngeal samples. Next-generation sequencing and comparative and phylogenetic analyses of influenza A virus genomes were performed. RESULTS: A total of 62 of 685 patients tested positive for influenza A virus, including 34 of 53 who were consulted in Mbacké in late September, six of 129 pilgrims who returned home in early October, and 20 of 42 villagers from October 3 to 29. A total of 27 genomes were obtained. Four clusters were observed based on the phylogenetic analyses, suggesting that Mbacké patients and returned pilgrims may have shared closely related viral strains with patients inhabiting the villages who did not participate in the GMT. CONCLUSIONS: Villagers in Ndiop and Dielmo may have been infected with viral strains originating from the GMT and possibly imported by pilgrims who returned from the GMT.

Influence of Microbiota on Clinical Expressions of Respiratory Viral Infections.

Respiratory infections, mainly due to viruses, are among the leading causes of worldwide morbidity and mortality. We investigated the prevalence of viruses and bacteria in a cross-sectional survey conducted in Dielmo, a village in rural Senegal with a population of 481 inhabitants. Nasopharyngeal sampling was performed in 50 symptomatic subjects and 101 asymptomatic subjects. Symptomatic subjects were defined as individuals presenting with clinical signs of respiratory infection, whereas asymptomatic subjects were recruited in the same households. The identification of pathogens was performed by polymerase chain reaction for 18 respiratory viruses and eight respiratory bacteria. The prevalence results for respiratory viruses detected in each study group demonstrated that 83.6% of symptomatic samples were positive for at least one respiratory virus, and 21.8% were detected in asymptomatic samples. Influenza A (P = 0.0001), metapneumovirus (P = 0.04), and enterovirus (P = 0.001) were significantly more prevalent in symptomatic patients. Overall, 82.0% of symptomatic subjects and 26.9% of asymptomatic subjects were positive for at least one respiratory bacterium. The most frequent pathogenic bacteria detected were Moraxella catarrhalis (56%) and Streptococcus pneumoniae (48.0%) among symptomatic individuals, whereas in asymptomatic subjects Corynebacterium propinquum was more prevalent (18%). A principal component analysis showed that parainfluenzas 2 and 4 were associated with asymptomatic subjects, whereas influenza A was associated with the presence of symptoms. Considering these results, a large epidemiological surveillance of the circulation of these respiratory pathogens in the general population should be conducted to provide a better understanding of their carriage and to potentially prevent epidemics.

Ornithodoros sonrai Soft Ticks and Associated Bacteria in Senegal.

The soft ticks, Ornithodoros sonrai, are known as vectors of the tick-borne relapsing fever caused by Borrelia spp. and have also been reported to carry other micro-organisms. The objective of this study was to collect and to identify O. sonrai ticks and to investigate the micro-organisms associated with them. In 2019, an investigation of burrows within human dwellings was conducted in 17 villages in the Niakhar area and in 15 villages in the Sine-Saloum area in the Fatick region of Senegal. Ticks collected from the burrows were identified morphologically and by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Micro-organism screening was performed by bacteria-specific qPCR and some identifications were made by standard PCR and gene sequencing. O. sonrai ticks were found in 100% (17/17) of the villages surveyed in the Niakhar area and in 66% (10/15) of the villages in the Sine-Saloum area. A total of 1275 soft tick specimens were collected from small mammal burrows. The ticks collected were morphologically identified as O. sonrai. About 20% (259/1275) of the specimens were also submitted to MALDI-TOF MS for identification. Among the resulting MS profiles, 87% (139/159) and 95% (95/100) were considered good quality specimens, preserved in alcohol and silica gel, respectively. All spectra of good quality were tested against our MALDI-TOF MS arthropod spectra database and identified as O. sonrai species, corroborating the morphological classification. The carriage of four micro-organisms was detected in the ticks with a high prevalence of Bartonella spp., Anaplasmataceae, and Borrelia spp. of 35, 28, and 26%, respectively, and low carriage of Coxiella burnetii (2%). This study highlights the level of tick infestation in domestic burrows, the inventory of pathogens associated with the O. sonrai tick, and the concern about the potential risk of tick involvement in the transmission of these pathogens in Senegal.

Description of Streptococcus thalassemiae sp. nov., a Bacterium Isolated from Human Blood.

Blood is a precious biological liquid that is normally sterile. Therefore, bacteria in the bloodstream are shown a priori anomaly. A blood culture is systematically performed to diagnose the cause of the bacteremia. Indeed, a patient received in our service had a thalassemia major and underwent a genoidentical transplant. Then, a blood test was performed to diagnose a four-day fever. In this context, we have isolated strain Marseille-Q2617 from the blood sample. It revealed a new bacterial strain that belongs to the genus Streptococcus. It is a Gram-positive coccus, nonmotile, and nonspore forming. The major fatty acid found is hexadecanoic acid, with 49.5%. A taxonomic method was used to characterize the strain by studying their phenotypic, phylogenetic, and genomic characteristics. In addition, sequence analysis of the 16S rRNA gene shows that the strain Marseille-Q2617 has 99.94% sequence similarity to Streptococcus mitis. Average nucleotide identity (ANI) analysis for strain Marseille-Q2617T showed the highest similarity of 92.9% with S. mitis. The DNA-DNA hybridization value obtained (50.2%) between strain Marseille-Q2607 and S. mitis, its closest related species, was below the recommended threshold (<70%). Strain Marseille-Q2617T has a genome size of 2.02 Mbp with 40.5 mol% of G + C content. Based on these results, we propose a new species of the genus Streptococcus, for which the name Streptococcus thalassemiae sp. nov., Marseille-Q2617T (=CSUR Q2617 = CECT 30109) was proposed.

Monitoring compliance with Senegal's tobacco products packaging and labelling requirements 6 months after implementation of the law.

INTRODUCTION: As of December 2021, 22 countries and one jurisdiction in WHO African Region (AFRO) have adopted pictorial health warning labels on tobacco packaging, but only 13 have implemented them. In 2014, Senegal enacted a comprehensive tobacco control law, which requires strong provisions on tobacco packaging and labelling. The objective of this study was to assess the level of compliance with these provisions in Senegal 6 months after implementation. METHODS: Data collection took place in Senegal's capital city of Dakar across 12 districts in February 2018, following the Tobacco Pack Surveillance System Field Protocol developed by the Institute for Global Tobacco Control at Johns Hopkins Bloomberg School of Public Health. Unique tobacco packs were purchased from a total of 48 tobacco vendors, and compliance with new packaging and labelling provisions was assessed. RESULTS: In total, seven unique cigarette packs were confirmed to be legally available for sale in Dakar, Senegal. All packs complied with all health warning provisions (type, size, location, language and quitline information) as well as bans on quantitative emissions yields. However, no pack complied with the descriptive constituents and emissions statement required on the lateral side, and four of the seven packs violated the ban on misleading brand descriptors. CONCLUSIONS: AFRO countries have made substantial progress in adopting comprehensive tobacco control laws that bring them closer into alignment with the Framework Convention on Tobacco Control. This study found areas of effective implementation of FCTC recommended packaging and labelling requirements, as well as areas in need of stronger enforcement.

PCR investigation of infections in patients consulting at a healthcare centre over a four-year period during the Grand Magal of Touba.

BACKGROUND: Respiratory and gastrointestinal symptoms and febrile illness are the most common complaints among ill pilgrims attending the Grand Magal of Touba (GMT) in Senegal. METHODS: Patients presenting with respiratory or gastrointestinal symptoms or febrile systemic illnesses were recruited between 2018 and 2021 at a healthcare centre close to Touba. Respiratory, gastrointestinal and blood samples were tested for potential pathogens using qPCR. RESULTS: 538 patients were included. 45.5% of these were female, with a median age of 17 years. Of the 326 samples collected from patients with a cough, 62.8% tested positive for at least one virus, including influenza viruses (33.1%). A high positivity rate of bacterial carriage was observed for Haemophilus influenzae (72.7%), Streptococcus pneumoniae (51.2%) and Moraxella catarrhalis (46.0%). Of the 95 samples collected from patients with diarrhoea, 71.3% were positive, with high rates of bacterial carriage, ranging from 4.2% for Tropheryma whipplei to 45.3% for Entero-pathogenic Escherichia coli. Of the 141 blood samples collected from patients with fever, 31.9% were positive including Plasmodium falciparum (21.3%), Borrelia sp. (5.7%) and dengue virus (5.0%). CONCLUSION: This study provides insight into the aetiology of most common infections at the GMT on which to base therapeutic options.

A review of the literature of Listeria monocytogenes in Africa highlights breast milk as an overlooked human source.

According to the latest WHO estimates (2015) of the global burden of foodborne diseases, Listeria monocytogenes is responsible for one of the most serious foodborne infections and commonly results in severe clinical outcomes. The 2013 French MONALISA prospective cohort identified that women born in Africa has a 3-fold increase in the risk of maternal neonatal listeriosis. One of the largest L. monocytogenes outbreaks occurred in South Africa in 2017-2018 with over 1,000 cases. Moreover, recent findings identified L. monocytogenes in human breast milk in Mali and Senegal with its relative abundance positively correlated with severe acute malnutrition. These observations suggest that the carriage of L. monocytogenes in Africa should be further explored, starting with the existing literature. For that purpose, we searched the peer-reviewed and grey literature published dating back to 1926 to date using six databases. Ultimately, 225 articles were included in this review. We highlighted that L. monocytogenes is detected in various sample types including environmental samples, food samples as well as animal and human samples. These studies were mostly conducted in five east African countries, four west African countries, four north African countries, and two Southern African countries. Moreover, only ≈ 0.2% of the Listeria monocytogenes genomes available on NCBI were obtained from African samples, contracted with its detection. The pangenome resulting from the African Listeria monocytogenes samples revealed three clusters including two from South-African strains as well as one consisting of the strains isolated from breast milk in Mali and Senegal and, a vaginal post-miscarriage sample. This suggests there was a clonal complex circulating in Mali and Senegal. As this clone has not been associated to infections, further studies should be conducted to confirm its circulation in the region and explore its association with foodborne infections. Moreover, it is apparent that more resources should be allocated to the detection of L. monocytogenes as only 15/54 countries have reported its detection in the literature. It seems paramount to map the presence and carriage of L. monocytogenes in all African countries to prevent listeriosis outbreaks and the related miscarriages and confirm its association with severe acute malnutrition.

Risk factors for symptoms of infection and the acquisition of pathogens among pilgrims at the Grand Magal of Touba, 2017-2021.

BACKGROUND: Respiratory and gastrointestinal symptoms are frequent in pilgrims at the Grand Magal of Touba (GMT). METHODS: Pilgrims were prospectively investigated in 2017-2021 for demographics, chronic conditions, preventive measures, respiratory and gastrointestinal symptoms, and pathogen carriage using PCR assays. RESULTS: 535 pilgrims were included. 54.8% and 13.3% reported respiratory and gastrointestinal symptoms, respectively. 18.4% acquired respiratory viruses, notably rhinovirus (10.1%) and coronaviruses (5.6%) and 39.9% bacteria, notably Haemophilus influenzae (18.9%) and Streptococcus pneumoniae (14.1%). The acquisition of gastrointestinal pathogens was lower, with enteroaggregative Escherichia coli (18.9%) and enteropathogenic Escherichia coli (10.5%) being the most frequent. A decrease was observed in the acquisition rates of pathogens in 2020-2021 GMT. Female pilgrims were more at risk of respiratory and gastrointestinal symptoms. Respiratory symptoms were associated with virus acquisition (aRR: 2.20, 95%CI [1.38-3.50]) and S. pneumoniae acquisition (aRR: 2.76, 95%CI = [1.64-4.62]). Using hand soap was associated with a decrease in the acquisition of rhinovirus (aRR: 0.42, 95%CI [0.22-0.80]) and coronavirus (aRR: 0.42, 95%CI [0.22-0.81]). Using face masks was associated with a decrease in reporting of respiratory symptoms (aRR: 0.54, 95% [0.35-0.86]). CONCLUSION: Hand washing with soap and wearing face masks should be recommended to GMT pilgrims.

Collinsella ihumii sp. nov., a new anaerobic bacterium isolated from human stool.

Strain GD8 is a new species belonging to the order Coriobacteriales that was isolated from fresh stool of a French volunteer. It is an anaerobic Gram-positive bacterium isolated from human gut microbiota. The sequence analysis of the 16S rRNA gene showed that our strain GD8 was 96.2% of similarity with Collinsella massiliensis strain An5 which was the phylogenetically related species. Its genome size is 2,836,446 bp with 64.1 mol% of G + C content. Strain GD8T (= CSUR P2019 = DSM 101062) is the type strain of the new species Collinsella ihumii sp. nov.

Detection of Coxiella burnetii and Borrelia spp. DNA in Cutaneous Samples and in Household Dust in Rural Areas, Senegal.

Q fever and tick-borne borreliosis are two zoonotic diseases rarely diagnosed in Senegalese health facilities, particularly in rural areas. Our study aims to better understand the circulation of Coxiella burnetii and Borrelia spp. DNA on human skin and the domestic environment in rural areas. Cutaneous swabs were taken from febrile patients being treated for borreliosis and/or Q fever, the members of patients' households and control households in the Niakhar area. Dust samples were also collected from 90 households where 54 cases of borreliosis and Q fever were reported as well as from the households of members of control populations in Dielmo, Ndiop, and Niakhar. C. burnetii and Borrelia spp. DNA were detected by quantitative PCR in cutaneous swabs and dust samples targeting spacers IS1111_IS30A and Bor 16S gene. Of 1365 persons tested, 76 were shown to carry C. burnetii, 13 Borrelia spp., and 6 were identified as carrying both C. burnetii and Borrelia spp. The prevalence of Borrelia spp. DNA in households was 16.7% in Dielmo, 6.7% in Ndiop, and 23.3% in all other villages in the Niakhar area, and the presence of C. burnetii in the same localities was 10%, 13.3% and 66.7%, respectively. Furthermore, C. burnetii genotyping identified the presence of Multispacer Sequence Typing group 6. These results revealed for the first time the carriage on the skin of C. burnetii and Borrelia spp. DNA in humans and its wide distribution across households. Our findings suggest that many populations are exposed to these diseases, with frequent contaminating cases of infectious origin arising from the domestic environment.

Respiratory infections among pilgrims at the Grand Magal of Touba: A comparative cohort controlled survey.

BACKGROUND: The Grand Magal of Touba (GMT) is a large event gathering around 4-5 million participants every year. A pilot study conducted in 2017 among GMT pilgrims showed that 41.8% of participants reported respiratory symptoms, mostly due to rhinovirus (13.0%), coronaviruses (16.0%) and adenovirus (4.6%). METHODS: A PCR-based prospective cohort study was conducted among GMT pilgrims and controls (who did not participate to the event) in two rural villages in South Senegal, in 2019. RESULTS: 93 pilgrims and 84 controls were included in the study. There were no significant differences between pilgrims and controls regarding demographic characteristics and chronic conditions. 60.2% of pilgrims reported respiratory symptoms during their stay in Touba, or soon after their return. By contrast, only 8.3% of controls reported respiratory symptoms after the GMT. The acquisition of rhinovirus, coronaviruses, Streptococcus pneumoniae and Moraxella catarrhalis was 22.6%, 6.5%, 17.2% and 6.8% respectively in pilgrims and was significantly higher than in controls (3.6%, 0%, 4.8% and 1.2% respectively). Respiratory symptoms post-GMT were five times more frequent in S. pneumoniae carriers (aOR = 5.18, 95%CI = [1.98-13.57]). CONCLUSION: This study demonstrates that individuals who participated in the GMT were at higher risk of suffering from respiratory symptoms and that this was linked to the acquisition of S. pneumoniae.

Tick-borne relapsing fever Borreliosis, a major public health problem overlooked in Senegal.

BACKGROUND: Tick-borne relapsing fever (TBRF) is the most common vector-borne bacterial disease in humans in West Africa. It is frequently clinically confused with malaria. Our study aims to determine, on a micro-geographic scale, the conditions for the maintenance and spread of TBRF in the Niakhar district of Senegal. METHODOLOGY/PRINCIPAL FINDINGS: We conducted clinical, entomological and animal reservoir investigations. Field surveys were carried out in order to investigate the presence of Ornithodoros sonrai vector ticks and to detect Borrelia spp. by qPCR using the 16S rRNA and glpQ genes, respectively. Micromammal trapping series were carried out inside homes and Borrelia infection was detected using brain tissue qPCR. Capillary blood samples from febrile patients were also tested for Borrelia using qPCR. More than 97% (40/41) of the villages surveyed were infested with O. sonrai ticks. The prevalence of Borrelia spp. infections in ticks was 13% (116/910), and over 73% (85/116) were positively confirmed as being Borrelia crocidurae. Borreliosis cases accounted for 12% (94/800) of episodes of fever and all age groups were infected, with children and young people between the ages of 8-14 and 22-28 being the most infected by the disease (16% and 18.4%). TBRF cases occurred in all seasons, with a peak in August. In two species of small rodents that were found to be infected (Arvicanthis niloticus, Mus musculus), the proportion of Borrelia infection was 17.5% (10/57), and the highest prevalence of infection (40.9%, 9/22) was observed in A. niloticus. CONCLUSION/SIGNIFICANCE: Our study indicates that TBRF is an endemic disease in the Niakhar district, where children and young people are the most infected. Arvicanthis niloticus and O. sonrai ticks are massively present and appear to be the main epidemiological reservoirs causing its extensive spread to humans.

Permanent Draft Genome Sequences for Mesorhizobium sp. Strains LCM 4576, LCM 4577, and ORS3428, Salt-Tolerant, Nitrogen-Fixing Bacteria Isolated from Senegalese Soils.

The genus Mesorhizobium contains many species that are able to form nitrogen-fixing nodules on plants of the legume family. Here, we report the draft genome sequences for three Mesorhizobium strains. The genome sizes of strains LCM 4576, LCM 4577, and ORS3428 were 7.24, 7.02, and 6.55 Mbp, respectively.

Permanent Draft Genome Sequence of Rhizobium sp. Strain LCM 4573, a Salt-Tolerant, Nitrogen-Fixing Bacterium Isolated from Senegalese Soils.

The genus Rhizobium contains many species that are able to form nitrogen-fixing nodules on plants of the legume family. Here, we report the 5.5-Mb draft genome sequence of the salt-tolerant Rhizobium sp. strain LCM 4573, which has a G+C content of 61.2% and 5,356 candidate protein-encoding genes.

Permanent Draft Genome Sequence of Ensifer sp. Strain LCM 4579, a Salt-Tolerant, Nitrogen-Fixing Bacterium Isolated from Senegalese Soil.

The genus Ensifer (formerly Sinorhizobium) contains many species able to form nitrogen-fixing nodules on plants of the legume family. Here, we report the 6.1-Mb draft genome sequence of Ensifer sp. strain LCM 4579, with a G+C content of 62.4% and 5,613 candidate protein-encoding genes.

Genetic and genomic diversity studies of Acacia symbionts in Senegal reveal new species of Mesorhizobium with a putative geographical pattern.

Acacia senegal (L) Willd. and Acacia seyal Del. are highly nitrogen-fixing and moderately salt tolerant species. In this study we focused on the genetic and genomic diversity of Acacia mesorhizobia symbionts from diverse origins in Senegal and investigated possible correlations between the genetic diversity of the strains, their soil of origin, and their tolerance to salinity. We first performed a multi-locus sequence analysis on five markers gene fragments on a collection of 47 mesorhizobia strains of A. senegal and A. seyal from 8 localities. Most of the strains (60%) clustered with the M. plurifarium type strain ORS 1032T, while the others form four new clades (MSP1 to MSP4). We sequenced and assembled seven draft genomes: four in the M. plurifarium clade (ORS3356, ORS3365, STM8773 and ORS1032T), one in MSP1 (STM8789), MSP2 (ORS3359) and MSP3 (ORS3324). The average nucleotide identities between these genomes together with the MLSA analysis reveal three new species of Mesorhizobium. A great variability of salt tolerance was found among the strains with a lack of correlation between the genetic diversity of mesorhizobia, their salt tolerance and the soils samples characteristics. A putative geographical pattern of A. senegal symbionts between the dryland north part and the center of Senegal was found, reflecting adaptations to specific local conditions such as the water regime. However, the presence of salt does not seem to be an important structuring factor of Mesorhizobium species.

A cross-sectional evaluation of venous thromboembolism risk and use of venous thromboembolism prophylaxis in hospitalized patients in Senegal.

BACKGROUND: Venous thromboembolism is a common and preventable cause of morbidity and mortality in hospitalized patients. There is a lack of data on the distribution of risk factors and prophylaxis practices in sub-Saharan Africa. AIM: To assess the prevalence of venous thromboembolism risk in hospitalized patients and to determine the proportion of at-risk patients who receive prophylaxis. METHODS: The study was a cross-sectional hospital-based survey. On the basis of the global ENDORSE methodology, patients aged≥40 years admitted to a medical ward or those aged≥18 years admitted to a surgical ward were assessed for risk of venous thromboembolism by hospital chart review. Distribution of risk factors and coverage of prophylaxis in at-risk patients were determined using the 2004 American College of Chest Physicians evidence-based consensus guidelines. RESULTS: From October to November 2008, 520 patients (278 medical; 242 surgical) were enrolled in 12 hospitals across Senegal. Two hundred and ninety-eight (57%) were at risk of venous thromboembolism; 152 (57.4%) medical patients and 146 (60.3%) surgical patients. Among those at risk, 48 (31.6%) medical patients and 52 (35.6%) surgical patients received a prescription for prophylaxis. Among patients without contraindication to anticoagulants, 33.8% (46/136) on medical wards and 37.5% (48/128) on surgical wards received prophylaxis. CONCLUSION: The risk of venous thromboembolism was frequent in hospitalized patients in Senegal but only a few received the recommended prophylaxis. There is a need to implement a programme to improve venous thromboembolism awareness and prophylaxis.

Facteurs de risque de démence dans une population de personnes âgées sénégalaise

Description La démence est devenue un problème de santé publique. Dans le but d'une prévention, il est important de connaitre son épidémiologie au Sénégal. L'objectif de cette étude était d'identifier les facteurs de risque de démence dans une population de personnes âgées sénégalaises. Méthodes Une étude transversale a été réalisée du 01 Mars 2004 au 31 Décembre 2005 auprès d'une population de 872 personnes âgées de 55ans et plus utilisant le Centre Médicosocial et Universitaire de l'Institut de Prévoyance Retraite du Sénégal pour des soins. Par une étude en deux phases, des données sociodémographiques, sur le mode de vie, le réseau social, les antécédents ont été collectées à l'aide d'un questionnaire structuré complété par un examen clinique et une évaluation neuropsychologique. Le diagnostic de démence reposait sur des critères DSM IV-R