PERFORMANCE OF SIX SCREENING SCORES FOR OBSTRUCTIVE SLEEP APNOEA IN AN AFRICAN POPULATION.

Introduction: A screening tool for obstructive sleep apnoea (OSA) is useful in low-income countries where it may be difficult to access sleep recordings. The objective of this study was to assess the performance of six screening scores compared with objective sleep recording in an African population sample. Methods: This analysis is based on the "Benin Sleep and Society" (BeSAS) populational study in which respiratory polygraphy (PG) was performed using a type III device and OSA screening questionnaires (STOP, STOP-Bang, Berlin, NOSAS [≥ 8 and ≥ 5), No-Apnea, GOAL) were administered to participants. PG-defined OSA severity categories were defined according to the apnoea-hypopnoea index (AHI): mild (AHI 5 to <15/h), moderate (AHI 15 to <30/h) or severe (AHI≥30/h), and these were compared to score findings. Results: A total of 1810 subjects (mean age 45.4±14.6 years; 57.3% women) were included. For moderate to severe OSA, the area under the receiving operating characteristic (ROC) curve was greatest for GOAL and No-Apnea (0.70), followed by NoSAS5 (0.69). The highest sensitivity values were for NoSAS5 (0.73), No-Apnea (0.72), and GOAL (0.69), while NoSAS8 had the highest specificity (0.91), followed by Berlin (0.88) and GOAL (0.71). All scores performed poorly with respect to the positive predictive value (PPV), which was highest with NoSAS8 (0.38). Conclusion: This study provides the first comparison of the performance of screening scores for OSA in an African population. Although still low, PPV was highest with NoSAS8. Hence, NoSAS8 would be the screening method of choice for OSA in resource-constrained settings where formal sleep recordings are not accessible.

EVALUATION OF A MODIFIED EPWORTH SLEEPINESS SCALE TO RELIABLY ASSESS EXCESSIVE DAYTIME SLEEPINESS IN LOW-INCOME COUNTRIES: RESULTS FROM THE BENIN SOCIETY AND SLEEP (BESAS) STUDY.

Background: The Epworth Sleepiness Scale (ESS) is a tool widely used to assess excessive daytime sleepiness. Unfortunately, it is not reliable in low-income countries where situations such as reading a book, watching TV or driving a car are not common. The aim of this study was thus to assess the performance of a modified version of the Epworth scale in a low-income country. Methods: We used data from the Benin Society and Sleep (BeSAS) study where the ESS and a modified ESS (mESS) were administered to participants. In the mESS, questions four questions over eight were redesigned to reflect common living situations in Benin. The internal coherence of the mESS was assessed using the Cronbach alpha coefficient (CAC). The discriminatory ability of the scale was assessed by comparing the mean scores according to reported sleep quality, insomnia complaints and apnea-hypopnea index (AHI). Results: A total of 2909 participants were recruited, 1129 were male (38.9%) with a mean age (SD) of 44.7 (14.5) y. Overall, 52.4% (1526) completed all the mESS questions while 453 (15.6%) completed the standard ESS. The CAC of the mES was 0.86 showing good internal coherence. Concerning the discriminatory ability, mean scores for mESS were 7.8 for participants with ISI < 8 vs 9.2 for participants with ISI≥8 (p<0.001), 7.8 for participants withPSQI<5 vs 8.3 for participants with PSQI≥5 (p=0.03). No difference was found when comparing the participants participants using different cut-offs of AHI (15 and 30). Conclusion: The mES is more reliable than ES in the Beninese population. mESS shows good internal coherence and differentiates between insomniacs vs non-insomniacs and between good and poor sleepers. Although the mES is not a perfect score, it appears more relevant in the Benin population than the original Epworth scale but needs further validation/improvement in other low-income countries.

Prevalence of stroke survivors in Parakou in northern Benin: A door-to-door community survey.

INTRODUCTION: Stroke is a major public health problem with a high burden in Sub-Saharan Africa. We aimed to determine the prevalence of stroke in Titirou in Parakou. METHODS: It was a cross-sectional study using a door-to-door survey in Titirou (Parakou) from 15 march to 15 October 2016 and included 4671 adults. We did a two stages survey. In the first stage the World Health Organization (WHO) tool for the diagnosis of stroke in community was used. In the second phase all suspected cases underwent neurological exam and sometimes brain CT-scan. The WHO definition was used for the diagnosis of stroke. We recorded the socio-demographic data and the vascular risk factors. The prevalence was standardized on age according to the WHO type population. Multiple logistic regression was done to identify associated factors and estimate the adjusted prevalence ratio (aPR) and their 95% confidence interval (CI). RESULTS: The mean age of the subjects was 27.7±12.9 years with a sex ratio of 0.97. After screening 161 were suspected and 54 confirmed cases, the overall prevalence of stroke in Titirou was 1.156 per 100,000 inhabitants [95% CI: 0.850 to 1.426]. The age-standardized prevalence of stroke was 3223 cases per 100,000 inhabitants. The associated factors were age (aPR 1.7 [1.5-1.9] for 10 years), history of hypertension (aPR: 64.8 [46.1-108.9]), diabetes mellitus (aPR: 4.5 [1.6-12.3]), low consumption of fruits and vegetables (aPR: 2.3 [1.2-4.4]), history of heart disease (aPR: 6.0 [2.6-13.7]), family history of stroke (PR: 4.6 [2.1-10.0]). Among the 54 subjects who had a stroke 10 were able to perform the brain CT-Scan: 40% were hemorrhagic and 60% ischemic stroke. CONCLUSION: Our study showed a high prevalence of stroke in Titirou and suggested urgent action for prevention.

Knowledge, attitudes, and behavior among key people involved in the employment of people with epilepsy in southern Benin.

PURPOSE: This study aimed to investigate knowledge, attitudes, and behavior among individuals working to achieve, or promote, the employment and retention in employment of people with epilepsy (PWE) in Benin. METHODS: We interviewed 300 subjects using a self-administered questionnaire. RESULTS: Knowledge: 93% had heard of epilepsy; 8.8% had at least one person with epilepsy (PWE) in their family; and 67.3% had witnessed a person having epileptic seizures. Attitudes and behavior: 95.3% and 95%, respectively, expressed their views that PWE should be able to enter mainstream education and that PWE should marry; 76.4% considered PWE equal to themselves; and 28.6% reported they would not hire a PWE. We found some associations between demographic characteristics and knowledge, attitudes, and behavior among respondents. A few unhelpful aspects of knowledge, attitudes, and behavior were identified. CONCLUSIONS: Our study showed a fairly high level of accurate knowledge of epilepsy, but some misperceptions and unhelpful attitudes and practices toward PWE in Benin were noted. This study's findings can be used to help plan appropriate strategies based on correcting misperceptions concerning inclusion and retention in employment of PWE in Benin.

[Prevalence of dental caries in school in the city of Ouidah in 2013]. / Prévalence de la carie dentaire en milieu scolaire dans la ville de Ouidah en 2013.

INTRODUCTION: The tooth decay is considered according to the WHO as the fourth world plague, after cancers, cardiovascular diseases and HIV infection. It is about a multifactorial affection few studied in Benin. The purpose of this work was to study prevalence of the tooth decay in schools in the city of Ouidah. METHODS: We conducted a descriptive cross-sectional and analytical study from 27th to 31st May 2013. It focused on 497 students aged from 5 to 15 years of primary and secondary schools in Ouidah. Each child received a dental examination and oral interview which allowed us to have the demographic data and those concerning behavior. RESULTS: The study disclosed that 73% of subjects have toothbrush, but only 4% of them brush frequently their teeth (3 three times a day). 96% of subjects stated that they have never consulted a dentist. The decay prevalence was 49.7% and was correlated to factors such as frequency of brushing, frequency of consultation, history family and parents' assistance. The DMFT index was 0.7. On 369 absent and filled decayed teeth, we counted only a single filled tooth that is 0,2% of teeth. CONCLUSION: In Ouidah's schools, tooth decay is a worrying pathology. The fillings are virtually nonexistent. To provide students a better oral hygiene and healthier teeth, an oral health education module in schools and the integration of oral systematic visits of student's examination at school is required.

[Prevalence and characteristics of chronic pain with neuropathic component at Parakou in northern Benin in 2012]. / Prévalence et caractéristiques des douleurs chroniques avec caractère neuropathique en population générale à Parakou au nord du Bénin en 2012.

The burden of chronic and neuropathic pain is high making it an important public health problem. The epidemiology is not well known in the general population in sub-Saharan Africa. We aimed to determine the prevalence of chronic pain with a neuropathic component at Tititou in Parakou in northeastern Benin. A cross-sectional study was conducted from 1st April to 31 May 2012 and included 2314 people in a door-to-door survey. Chronic pain was defined as pain occurring for more than three months. Neuropathic pain was assessed with the DN4 score. A neurological exam was performed by a young physician for all people with chronic pain. During the interview, sociodemographic data, past medical history, weight and height were recorded. Multivariate logistic regression was performed to analyze the main associated factors. Among the 2314 people included in this survey, 49.7% were male. The mean age was 32.3 ± 13.1 years. Nine hundred seven reported pain occurring for more than 3 months. The prevalence of chronic pain was 39.2% (CI95%: 29.3-34.7). It was more frequent in females, older people, among diabetics, people with a history of any surgery, stroke, brain trauma, and alcoholism. The prevalence of chronic pain with a neuropathic component was 6.3% (CI95%: 5.0-7.9). The main associated factors were age, matrimonial status, professional occupation, body mass index, diabetes, history of zoster, history of any surgery, brain trauma. People with neuropathic pain often reported pain with burning (87.6%), prickling (82.8%), numbness (66.9%), tingling (63.4%), and lightning pain (48.3%). The main locations were the lower limbs and low back pain. This study suggested the high frequency of chronic neuropathic pain in the general population in Parakou compared with rates reported in western countries.

Prevalence of hypertension and associated risk factors in Benin.

BACKGROUND: Hypertension is one of the main risk factors of cardiovascular diseases. There has been a lack of data on this risk factor in the general population in Benin. The aim of this study was to determine the prevalence of hypertension and identify the associated risk factors in Benin. METHODS: A cross-sectional study was conducted from July to August 2008 in Benin's 12 departments. The questionnaire and anthropometric measurements of the World Health Organization STEPWISE survey were used. The sample included 6853 subjects 25-64 years of age, randomly selected by five-stage random sampling. Blood pressure was measured using standard procedures. Data was processed and analyzed using EPI DATA and STATA 9.2 software. Prevalence levels were compared using Pearson's chi(2) and means with the Student t-test. Univariate and multivariate regression analysis, taking the sampling method into account, was used to identify risk factors. RESULTS: The sample comprised 49.5% females, the 25- to 34-year-old age group was the largest, and the mean age was 42.7±12.4 years. The prevalence of hypertension was 27.9% [95% CI: 26.3-29.5%], 77.5% of the subjects were unaware of their high blood pressure, and 81.6% had not taken their drugs two weeks before the survey. Prevalence of known hypertension was 6.9%, prevalence of treated hypertension 4.8%, and prevalence of controlled hypertension 1.9%. Age and obesity were significantly associated with hypertension. Department and profession were not associated with hypertension. CONCLUSION: This study showed a high prevalence of hypertension in the general population in Benin. Better management of this risk factor will contribute to reducing morbidity and mortality due to cardiovascular diseases.

[Epidemiology of dementia in elderly living in the 3rd borough of Bangui (Central African Republic)]. / Épidémiologie des démences chez les personnes âgées dans le troisième arrondissement de la ville de Bangui (République Centrafricaine).

Given the gradual improvement of living conditions and aging, dementia and related syndromes are becoming serious problems in the developing countries. A cross-sectional door to door type study in neighbourhood, was conducted from October 2008 to January 2009, in the general population in Bangui, order to help get a better understanding of the prevalence and risk factors of dementia among people over 65 living in the Central African capital. Of the 496 elderly respondents, 188 had cognitive disorders. After a neuropsychological examination, 40 of these subjects were diagnosed with dementia. The prevalence of dementia was 8.1% (IC 95% = [5.7-10.5]). The average age of subjects with dementia, ranging from 65 to 90 years, was 76.0 ± 7.1 years. There was a significant risk of developing dementia for an increase of ten years old (OR = 2.6, 95% CI [1.5 to 4.5]). The sex-ratio was 6/34. 82.5% of the demented had never attended school. 70.0% showed a state of malnutrition (BMI ≤ 18,5 kg/m(2)), significantly associated with dementia (OR = 3.3; IC 95% = [1.5-7.3]). The blood pressure was high in 67.5% of demented which is significantly associated with dementia (OR = 2.4; IC 95% = [1.1-5.4]). A recent change in financial status was a factor significantly associated with dementia (OR = 6.4; IC 95% = [1.8-22.5]). These results support the existence of dementia in urban Africa. The observed prevalence is close to those found in high-income countries. Further studies should be conducted which includes both the rural and urban Africa, to better understand the problem and solutions consider to comprehensive care and prevention axes adapted to our context.

[Social representations of cardiovascular disease in the Tanvè Health Study (TAHES) cohort in Benin]. / Représentations sociales des maladies cardio-vasculaires dans la cohorte Tanvè Health Study (TAHES) au Bénin.

OBJECTIVE: To describe the social representations associated with cardiovascular diseases (CVD) in the village of Tanvè in Benin. METHODS: Focus groups discussions and semi-structured interviews were conducted among participants of Tanvè Health Study (TAHES) cohort. Audio recordings were made during the interviews, as well as some note-taking. Data were organized by themes and analyzed to identify key representations that underlie attitudes and health care practices. RESULTS: A total of 19 subjects (including 11 women) participated in 2 focus groups and 17 (including 5 women) in individual interviews. Etymologies of CVD's names evoke either clinical signs (example: ''tesisi glô mɛ'' [can't stand up]), guessed etiology (example: ''kuvitɔ zɔn'' [ghosts' disease]) or a local adaptation of a biomedical name (example: ''a'tension'' [from hypertension]), to cite the example of stroke. According to beliefs about etiology, diseases were classed as ''simple'' or "organic" diseases ("azɔn yaya") and ''supernatural'' or ''induced'' diseases linked to "azé" [immaterial witchcraft] or "bô" [material bewitchment]. Chronic or recurrent diseases usually end up in the ''supranatural'' category and induce the consultation of "bokɔnɔ᷉" (diviner) or other religious for diagnosis. Health care seeking refer to modern medicine, "amanɔn" (leaf-based care), "bokɔnɔ᷉" or traditional religious (various rites) and Christians (prayers). CONCLUSION: Social representations of CVD in this community are based on ancestral beliefs, but are also influenced by modern knowledge. Taking them into account could improve quality of health to fulfill communities' care needs.

Prevalence of migraine in a rural community in south Benin.

Migraine is a very common neurological disorder worldwide. Its prevalence is lower in developing countries. There were no data concerning the general population in Benin. We aimed to determine the prevalence of migraine in a rural community of Benin. A cross-sectional study was conducted in a rural area of Abomey from February to April 2003 and included 1113 persons selected by a two-stage survey. A case was defined according to International Headache Society criteria (1988). Of the 1113 persons, 37 had migraine. The lifetime prevalence of migraine was 3.3% (male 2.2%, female 4.0%). The peak prevalence was found in persons in the second decade of life. Higher levels of education were associated with migraine. Migraine without aura was the more frequent form (67.5%). The most frequent triggers of migraine were annoyance (73.0%), exposure to the sun (73.0%), heat (65.0%) and anxiety (51.4%). The low prevalence rate of migraine in Benin confirmed the results of the few available African studies. The disease is severe and occurs in a young population and could lead to a high socio-economical burden.

[Management of stroke in sub-Saharan Africa: current issues]. / Prise en charge des accidents vasculaires cérébraux en Afrique subsaharienne.

In sub-Saharan Africa, stroke is likely to present an increasingly important public health problem with a larger relative share of overall morbidity and mortality. Overall, sub-Saharan Health Care is characterized by a lack of human resources, lack of facilities for special investigations, and especially an absence of specific programs addressing the prevention of cardiovascular conditions. Current data on the epidemiology of stroke in sub-Saharan Africa, although sparse and fragmentary, indicate a comparatively high incidence of cerebral hemorrhage associated with high blood pressure, while ischemic stroke in black Africans still appears to be related primarily to small artery disease, HIV infection, and sickle cell disease. With urbanization, the role of large-vessel atherosclerosis is increasing. It is thus essential to coordinate government funding, health care professionals and development agencies to address this rising health problem. Access to health care needs to be better structured, and screening programs should be developed in order to identify and treat vascular risk factors. Improved training of health care professionals is also required in the areas of prevention, diagnosis and management of stroke. Implementation of best-practice recommendations for the management of stroke adapted to the specificities and resources of African countries would help rationalize the scarce resources currently available.

Distal sensory polyneuropathy among HIV-infected patients at Parakou University Hospital, Benin, 2011.

Distal sensory polyneuropathy (DSP) is the most frequent neurological complication among HIV patients, and its risk increases with use of highly active antiretroviral therapy (HAART). We aimed to assess the prevalence of DSP and the factors associated with it among HIV-infected outpatients treated at Parakou University Hospital. This cross-sectional study took place from April 15 to July 15, 2011, and included 262 patients. All patients underwent a neurological examination by two neurologists with training and clinical experience in these examinations and in the Brief Peripheral Neuropathy Screening (BPNS), which was the primary tool used here. Data from nutritional status (body mass index: BMI), social and demographic information, HAART status, and CD4 count were recorded. The factors associated with DSP were studied with multivariate analysis, using a logistic regression model and a significance level of 0.05. The study included 60 men (22.9 %). Patients' ages ranged from 16 to 74 years and averaged 36.8±10 years. All patients but one patient were infected by HIV type 1 only; that one was coinfected by types 1 and 2. The mean BMI was 22.5+/-4.2 kg/m2. In all, 213 (81.3 %) received HAART, and the mean CD4 count was 355.0 cells/mm3+/-236.1. The prevalence of DSP was 42.4 %. The factors associated with it on univariate analysis were age, marital status, HAART status, duration of HIV infection, and duration of HAART. Only advanced age (OR 1.8, 95 % CI 1.1-5.3) and HAART use (OR 2.3, 95 % CI 1.5-4.9) were associated with DSP in the multivariate analysis. The main symptoms were paresthesia (numbness:75.7%; burning: 39.6%; pins and needles sensation 32.4 %) and pain (23.4 %). Vibration perception at the toes was missing or reduced for 84.4 %. According to the sensory symptoms grade, 93.7 % of patients were classified in Grades 2 or 3. This study showed that the prevalence of DSP is high and that it is associated with age and HAART.

[Factors associated with quality of life for patients with post-stroke aphasia in the Cotonou hospitals, Benin]. / Facteurs associes a la qualite de vie des aphasiques post accident vasculaire cerebral en milieu hospitalier a cotonou, Benin.

INTRODUCTION: The objective of this study was to determine the factors influencing quality of life for patients with post-stroke aphasia followed in Cotonou hospitals. METHOD: A prospective descriptive and analytical cross-sectional study was conducted in CNHU-HKM (Cotonou, Benin) from October to December 2012; focusing on patients with at least six months of post-stroke aphasia. For each patient, a SIP-65 questionnaire was administered. The Epi Info 3.5 software was used for data analysis. A multivariate analysis was performed to determine factors associated with quality of life for patients with aphasia. RESULTS: In total, 41 patients were included in this study with a sex ratio of 1.3. The average age was 55.3 ± 2.5 years. The average duration of the aphasia was 10 months. Broca's aphasia was predominant (68.3%). 60.8% of aphasia patients were able to preserve their quality of life. Multivariate analysis showed that age, family support, the type of stroke and aphasia and speech therapy were associated with quality of life. CONCLUSION: The treatment of post-stroke aphasia must incorporate these factors associated with quality of life for a better recovery of patients.

INTRODUCTION: L'objectif de ce travail était de déterminer les facteurs influençant la qualité de vie des patients aphasiques post-AVC suivis à Cotonou. MÉTHODE: Il s'agit d'une étude transversale, prospective descriptive et analytique qui s'est déroulée au CNHU-HKM de Cotonou d'Octobre à Décembre 2012; elle a inclus les patients aphasiques post-AVC d'au moins six mois. Pour chaque patient, un questionnaire SIP-65 a été administré. Le logiciel Epi info 3.5 a servi de base à l'analyse des données. Une analyse multivariée a été effectuée pour déterminer les facteurs associés à la qualité de vie des aphasiques. RÉSULTATS: Au total, 41 patients ont été inclus dans l'étude avec une sex-ratio de 1,3. L'âge moyen était de 55,3 ± 2,5 ans. La durée moyenne d'évolution de l'aphasie était 10 mois. L'aphasie de Broca était prédominante (68,3%). 60,8% des aphasiques avaient une qualité de vie préservée. L'analyse multivariée a montré que l'âge, le soutien de la famille, le type d'AVC et d'aphasie et le traitement orthophonique étaient associés à la qualité de vie. CONCLUSION: La prise en charge des aphasiques post-AVC doit intégrer ces facteurs associés à la qualité de vie pour une meilleure récupération des patients.

[Epidemiology of epilepsy in sub-Saharan Africa: a review]. / Epidémiologie de l'épilepsie en Afrique subsaharienne : une revue de la littérature.

Epilepsy is, above all tropical, moreover, very african in its frequency and gravity. Data on the prevalence of epilepsy shows it to be two or three times more prevalent in tropical zones than in industrialized countries in non tropical areas, however it is rare to find data on the incidence and prognosis of epilepsy in sub-Saharan Africa. It is difficult to determine the relative contribution of each of the causes of epilepsy. Only a few case-control studies have been carried out in sub-Saharan Africa. Infectious diseases, in particular parasitic diseases such as neurocysticercosis or cerebral malaria, seem to be the cause of the majority of the cases of epilepsy. However it is necessary to do additional epidemiological studies to determine the etiologies of epilepsy more precisely in sub-Saharan Africa.

[Socio-cultural aspects of epilepsy in a rural community in northern Benin in 2011]. / Aspects socioculturels de l'épilepsie dans une communauté rurale au nord Bénin en 2011.

Despite the development of knowledge in diagnosis and therapeutic of epilepsy it remains to be cause of rejection and stigma. We aimed to study the knowledge, attitude and practice toward epilepsy and the stigma in a rural community. The cross-sectional study was carried out from 1st to 31st March 2011 in a rural community (Tourou) at Parakou in the northern Benin. It was a door-to-door survey and included 1 031 adults older than 15 years. The diagnosis of epilepsy was based on International League Against Epilepsy. The specific questionnaire was used and comprised 16 items which explored knowledge, attitude and practice toward epilepsy. Another questionnaire was developed to study stigma among epileptics. The associated factors to the misconception toward epilepsy have been studied. All adults have heard about epilepsy and knew the generalized tonic-clonic form of epilepsy and knew someone with epilepsy. Hereditary (98%) and witchcraft (97.9%) and social problems (65.9%) were mentioned as the most cause of epilepsy. Epilepsy was cited as contagious disease by 90.6% of respondents and the associated factors were the sex (p=0.005) and occupational status (0.024). The saliva (98.1%) and witness of the place of seizure (97.8%) were the frequently mentioned modes of transmission. 65% of all mentioned that epileptics can not get marriage and the main associated factors to this belief were the advanced age (p=0.008) and occupational status (0.004). 64.4% believed that children with epilepsy shouldn't be attend to school, age (0.004), ethnicity (0.047) and occupational status were the associated factors with this misconception. Despite 99.4% considered epilepsy as treatable disease only 12.7% would have referred epileptics to the hospital. All the seven epileptics considered themselves as victims of stigma and rejected by their family and the community. The misconceptions associated to the epilepsy can explain the stigma and the therapeutic gap in this rural community.

Seroepidemiology of human T-cell lymphotropic virus type I/II in Benin (West Africa).

In 1988-1989, a national survey was conducted in Benin to determine the distribution of HTLV-I infection in a representative sample of adult individuals. This study comprised 2625 healthy subjects recruited in the six provinces of Benin and 1300 blood donors from Cotonou and from the other five provinces. Sera were screened for HTLV-I antibody by both immunofluorescence (IF) and enzyme immunoassay (EIA). Sera positive or doubtful by at least one technique were further analyzed by Western blot and radioimmunoprecipitation assay (RIPA) when indeterminate. Samples were considered as positive if they reacted with two gene products. No blood donor was positive. Over the 2625 subjects, 39 (1.5%) were positive. We observed a statistical difference between male and female (1%, 2%, p less than 0.05). A difference was also observed according to the areas studied: the HTLV-I antibody rate increased from coastal (0.3%) to northern (5.4%) provinces. HTLV-I seroprevalence increased significantly with age. This survey shows that HTLV-I infection exists in Benin but varies according to regions.

PIP: Researchers enrolled 2625 15 years old healthy individuals from the general population and 1300 blood donors of Benin to determine the extent of HTLV-I infection in Benin. They followed the recommended laboratory techniques of the US Public Health Service Working Group (1988). No blood donors were HTLV-I seropositive. The sera of 1.5% of the general population sample tested positive for HTLV-I. This rate was comparable to other western African countries. A significantly higher percentage of females were seropositive than males (2% vs. 1%; p.05), especially among the rural population (2.6% vs. 0.6%). No significant difference in seroprevalence existed between urban and rural areas overall (1.3% vs. 1.7%) and between urban males and females (1.4% vs. 1.1%), however. Further HTLV-I seroprevalence increased significantly as one went from south to north (0.6% in the 3 south coastal provinces, 1.1% in the central province, and 3.2% in the 2 northern provinces; p.001). In fact, the northern province of Atakora had the highest HTLV-I seroprevalence rate (5.4%), especially among females (p.0005), and was significantly higher than the other provinces (p.001). Research have since begun in several villages in Atakora to detect possible clusters and analyze associations between HTLV-I seroprevalence and life style, environmental and geographic factors, and concomitant infections such as filariasis. Seroprevalence also increased with age. For example, 0.4% of males 30 years old had HTLV-I antibodies compared to 1.8% of those 30 years old (p.02). In addition, 0.4% of females 20 years old had HTLV-I antibodies compared to 2.4% of those 30 years old (p.05). The researchers noted that other epidemiologic studies in Benin have begun to assess the prevalence of tropical spastic paraparesis with or without the association of HTLV-I and adult T-cell leukemia.

Estimation of the prevalence of epilepsy in the Benin region of Zinvié using the capture-recapture method.

BACKGROUND: The prevalence of epilepsy was estimated in two villages of 3134 inhabitants, in Benin, in April and May 1997 using the capture-recapture method. METHODS: Information was obtained from (i) a door-to-door cross-sectional study, (ii) a non-medical source consisting of key informants (traditional practitioners, teachers, village leaders, and religious representatives) and (iii) a medical source through evaluation of medical records in health centres. In all the three situations, the diagnosis of epilepsy was confirmed by a neurologist. RESULTS: The door-to-door survey found 50 epileptics, i.e. a prevalence of 15.9 per 1000. The non-medical source found 26 patients. The medical source found only four patients. In total, 66 epileptics were found by combining the three sources, giving a prevalence of 21.1 per 1000. After application of the capture-recapture method, the estimated number of cases from the door-to-door survey and non-medical source was 105, and 110 cases when the medical source was considered as well. The respective prevalences were 33.5 per 1000, and 35.1 per 1000. CONCLUSIONS: The door-to-door survey has been usefully improved by using key informants. The epilepsy prevalence estimate found by capture-recapture is clearly higher than that found by traditional cross-sectional methods, and could better depict the frequency of epilepsy in Africa.

Intrafamilial clustering and 4-year follow-up of asymptomatic human T-cell leukaemia virus type I (HTLV-I) infection in Benin (West Africa).

BACKGROUND: Few data exist concerning familial human T-cell leukaemia virus type I (HTLV-I) carrier states and transmission in African countries. Two previous surveys performed in Benin in 1989 and 1990 using a three-level cluster sampling method allowed us to identify HTLV-I positive subjects. The evolution of HTLV-I within the families of these subjects is described over a 4-year period, 1991-1995. METHODS: Since 1991, 37 HTLV-I seropositive subjects, six subjects with indeterminate Western-Blot pattern, and their relatives have been followed up once a year clinically and biologically. RESULTS: Twenty-three mothers in the study group gave birth to 27 children between 1991 and 1995. Among the 13 infants born to the 12 seropositive mothers, two seroconverted before their second birthday. One adult woman whose husband was seropositive developed seropositivity 4 years after marriage. In March 1992, a family case-control study (proband study) was conducted. A seroprevalence of 27.5% was found among 138 relatives of 32 infected subjects and 1.4% among 142 relatives of 32 control subjects. CONCLUSIONS: There is clearly an intrafamilial clustering of HTLV-I in Benin. The annual incidence density of HTLV-I in this cohort is estimated at 6 per thousand.

Detection and characterization of autoantibodies directed against neurofilament proteins in human African trypanosomiasis.

In serum and in cerebrospinal fluid (CSF) from patients with human African trypanosomiasis (HAT) with central nervous system involvement, we detected autoantibodies directed to some proteins from these tissues. The characterization of antigenic proteins by Western blotting showed that the antibodies recognized the 200-kD and 160-kD proteins of neurofilament (NF). Serum anti-NF antibodies were more frequent in HAT patients than in control subjects (86% versus 24%; P < 10[-9]) and they belonged predominantly to the IgM class (anti-NF IgM = 86% versus anti-NF IgG = 4%; P < 10[-9]) in the patients with stage II (central nervous system involvement) HAT. The CSF antibodies to NF were IgM in 88% (22 of 25) of the cases and IgG in 32% (8 of 25) of the cases. Epitopes shared by NF and trypanosomes were detected by indirect immunofluorescence and this was confirmed by the disappearance of anti-NF reactivity after adsorption with trypanosome antigens (Trypanosoma brucei brucei or T. b. gambiense). Anti-NF antibodies were undetectable in the CSF from stage I HAT patients.

Seroprevalence of cysticercosis in Bénin.

We report the results of a seroepidemiological study on the prevalence of cysticercosis in Bénin. Cluster sampling at 3 levels was performed in the 6 départements (Atacora, Borgou, Zou, Mono, Atlantique and Oueme) and 2625 serum samples, from 1329 adult females and 1296 adult males, were collected. Antibodies against Taenia solium cysticerci were first searched for by enzyme-linked immunosorbent assay and the 41 seropositive samples were then examined by enzyme-linked electroimmunotransfer blot assay (EITB). Thirty-five samples gave positive results in the EITB. The overall seroprevalence of cysticercosis was therefore 1.3% (95% confidence interval [95% CI] 0.9-1.9). The seroprevalence was 1.9% in males (95% CI 1.2-2.7) and 0.8% (95% CI 0.4-1.5) in females (P < 0.05). A progressive increase in seroprevalence with increasing age was found. The highest seroprevalences were observed in Atacora and Atlantique, 2 non-Muslim départements (3.3% and 3.0%, respectively). This study demonstrated the public health importance of cysticercosis in Bénin.