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International audience; Background: Artesunate-amodiaquine (AS-AQ) and artemether-lumefantrine (AL) are first-and second-line treatments for uncomplicated Plasmodium falciparum malaria in Gabon. AL remains highly efficacious, but its widespread use has led to molecular selection of the NFD haplotype on Pfmdr1 and K76 in Pfcrt. In this study, plasmodial infection characteristics and the distribution of the Pfmdr1 and Pfcrt genotypes involved in reduced efficacy of artemisinin-based combination therapy (ACT) were investigated in four Gabonese localities. Methods: A cross-sectional study was conducted in the paediatric units of rural (Lastourville and Fougamou), semiurban (Koula-Moutou) and urban (Franceville) areas. Malaria was diagnosed with the rapid diagnostic test Optimal-IT (R) and confirmed by blood smear. Pfmdr1 codons 86, 184 and 1246 and Pfcrt codon 76 were genotyped by PCR-RFLP and sequencing. Results: Among 1129 included children, the prevalence of plasmodial infection was 79.5 % at Lastourville, 53.6 % at Fougamou, 36.1 % at Koula-Moutou, and 21.2 % at Franceville. The prevalence was significantly higher among children over 60 months of age in both semi-urban (p = 0.01) and urban (p = 0.004) areas. The prevalence of Pfmdr1 wild-type N86 differed significantly between Lastourville (57.8 %) and Koula-Moutou (45.4 %) (p = 0.039). No difference in 184F-carrying parasites was found between Lastourville (73.8 %), Fougamou (81.6 %), Koula-Moutou (83.2 %), and Franceville (80.6 %) (p = 0.240). The prevalence of wild-type D1246 was significantly different between Lastourville (94.1 %), Koula-Moutou (85.6 %) and Franceville (87.3 %) (p = 0.01). The frequency of wild-type K76 was not significantly different across the four sites: Lastourville (16.5 %), Fougamou (27.8 %), Koula-Moutou (17.4 %), and Franceville (29.4 %) (p = 0.09). The mixed genotypes were only found in Lastourville and Franceville. The NFD, YFD and NYD haplotypes were mainly Lastourville (46.6, 25.8, 14.0 %), Fougamou (45.5, 9.1, 42.4 %), Koula-Moutou (35, 6.7, 40.4 %), and Franceville (40.0, 16.0, 32.0 %). Conclusion: This study shows an increase in the prevalence of childhood plasmodial infection in Gabon according to the low socio-economic level, and a high frequency of markers associated with AL treatment failure. Close monitoring of ACT use is needed.

International audience

International audience; PURPOSE: Estimate the prevalence of epilepsy in the 15 years and older in Benin. METHODS: We used a random multistage sampling design to select a representative sample of the 15 years and older in Benin. From March to May 2010, people were screened door-to-door in the twelve regions of Benin. Screening and data collection were performed using a validated standardised questionnaire of epilepsy in tropical regions. A neurologist examined all people suspected of epilepsy. RESULTS: We identified 174 suspected epilepsy cases from 13,046 screened people; 105 were confirmed by the neurologist (54 men and 51 women). The mean age of PWE was 28.9±14.3 years. The estimate of crude prevalence of epilepsy in the 15 years and older in Benin was 8.05/1000 (95% CI: 6.52-9.58/1000). The crude prevalence of epilepsy among men was 9.77/1000 (95% CI 7.35-12.73/1000) and 6.79/1000 (95% CI 5.06-8.91/1000) for women. The age-adjusted prevalence of epilepsy on sub-Saharan Africa population was 8.25/1000 and 7.33/1000 on world population. Substantial heterogeneity was noted, with differences from one region to another. The most common seizure types were generalised tonic-clonic (80.0%), partial secondary generalised seizures (14.3%) and partial seizures (5.7%). SIGNIFICANCE: This nationwide study is the first in West Africa. It provides a low prevalence of epilepsy in Benin compared to previous studies performed in this country and in neighbouring countries. Restricted-area studies are often motivated by the presence of specific risk factors and could overestimate the prevalence, while large-scale studies could underestimate other subtle forms of epilepsy.

Background Malaria remains a major public health problem, due largely to emergence and widespread P. falciparum drug resistance. WHO recommends artemisinine combination based therapy (ACT) to overcome P. falciparum drug resistance, but reports of declining ACT efficacy have been published. A thorough understanding of the molecular bases of P. falciparum resistance to existing drugs is therefore needed. The aims of this study were to analyze the in vitro sensitivity of P. falciparum field isolates from Franceville, Gabon, to chloroquine (CQ), mefloquine (MF), dihydroartemisinine (DHA) and monodesethylamodiaquine (MDAQ), and to investigate polymorphisms associated with drug resistance. Methods We conducted a cross-sectional study of 53 field isolates. Field isolates sensitivity to CQ, MF, DHA and MDAQ was assessed using the colorimetric DELI test. The Pfmdr1 codons 86 and 1246, Pfcrt (haplotype codon 72 to 76) and the PfATPAse6 codons 110 and 2694 were analysed by PCR-RFLP. Associations between drug sensitivity and parasite gene polymorphisms were evaluated with the Chi square test, and routine hematological parameters were analyzed with Fisher’s exact test implemented with Epinfo software. In all statistical tests, significance was assumed at p Results A total of 46 P. falciparum isolates were successfully cultured in vitro and their sensitivity was tested. The proportions of isolates resistant to CQ, MF and MDAQ were 43.5%, 23.4% and 56.5%, respectively. Some isolates (23.9%) had DHA IC50 values higher than 10 nM. The median IC50 values were 71.67 (interquartile range (IQR, 1–438.2), 6.59 (IQR, 0.08-96), 64.79 (IQR, 0.09-448) and 6.45 nM (IQR, 0.09-23) for CQ, MF, MDAQ and DHA, respectively. The strongest correlation between diminished DHA sensitivity and MF resistance was observed (r2=0.73), followed by correlation between diminished DHA sensitivity and CQ resistance. Cross-resistance between CQ and MF was also observed. The prevalence of the 86Y and 1246Y mutations in Pfmdr1, 76T in Pfcrt, and 110A and 2694T in PfATPase6 was respectively 42% and 17.1%, 97.8%, and 0% and 22.2%. Conclusion These high levels of antimalarial drug resistance in Franceville, Gabon, call for reinforced surveillance of drug efficacy.

International audience

International audience; The strategies recently implemented in Gabon have been effective in improving immunization coverage. These include, in particular, the integration of the Expanded Programme on Immunization (EPI) in primary health care centers, the integration of immunization outside of EPI, immunization by peripheral health centers according to pre-set advanced strategies, and awareness and catch-up campaigns. This descriptive, cross-sectional survey was conducted from 1 October 2007 through 30 January 2008, throughout public- and private-sector health care centers in the town of Libreville. In the public sector, where health care is free, the study took place at the largest health facility in the country, the Hospital Center of Libreville (HCL), at Estuary Mélen Hospital (on the outskirts of Libreville), at Nkembo Hospital, which houses the EPI offices, and the 5 Maternal and Child Health centers (MCH) where vaccine monitoring is done. Monitoring in the private sector covered only the three largest clinics, where vaccine monitoring is done, all of which agreed to participate. After obtaining informed consent from the parents or guardian accompanying the child, a semi-structured interview according to a standardised questionnaire was conducted to collect socioeconomic and demographic data, including age, sex, recruitment site, place of residence, number of siblings, parental origin, ethnicity of head of household, type of family (couple or single parent), mother's age, level of education, employment and socio-economic status, as determined by the head of household's monthly income (in three categories: 1) low income, at or below the minimum wage, set at 80 000 FCFA (120 euros); 2) average income, from more than 80 000 FCFA to 300 000 FCFA (458 euros); and 3) high income over 300 000 FCFA. After the interview, the child's vaccination booklet was carefully examined to identify the types of antigen, number of doses administered, age at vaccination, and the regularity of the monitoring. Parents were asked to explain the reasons for any delays in or absences of vaccinations. EPI vaccines administered to children aged 0 to 11 months include: BCG (Calmette-Guérin bacillus); DPT3 (3rd combination dose for Diphtheria-Tetanus-Pertussis); Hib3 (3rdd dose of Haemophilus influenza b); OPV3 (3rd dose of oral polio vaccine); IPV3 (3rd dose of injectable polio vaccine, often in combination); HEB3 (3rd dose of Hepatitis B); yellow fever vaccine; and measles vaccine. The non-EPV vaccines for children aged 12 to 59 months included: HiB4; DPT4; HEB4; IPV4; MMR (combined Measles-Mumps-Rubella); meningococcal vaccine A and C; Typhim Vi (typhoid polysaccharide vaccine); and Pneumo 23 (pneumococcal vaccine.) Results: The study included 1001 children: 533 boys (53.2%) and 468 girls (46.8%), for a sex ratio of 1.1. The mean age of the sample was 12.0 ± 13.1 months, distributed as follows: 64.5% aged 0 to 11 months; 20.1% aged 12 to 24 months; and 15.4% aged 25 to 59 months. In all, 175 children (17.5%) came from the private sector, and 826 children (82.5%) from the public sector. Both parents lived with 696 children (69.5%), while the remaining 305 children (30.5%) lived with their mother. The mothers' mean age was 26 years (min/max: 15/49 years); 61.3% had completed secondary education, 19.1% superior level, 10.6% primary level and 9.0% had no education at all. Almost 37% of mothers had some sort of paid employment. Household income was distributed as follows: low income for 18.6%, average income for 47.2%, and high income for 34.3% of the families interviewed. The average number of children under the age of 15 in a household was 3 (±2). Among children aged 0 to 11 months, the EPI antigens had the highest vaccination coverage rates, and these rates were higher in the private sector (more than 80% to 99% for some). Overall, the BCG scar was seen in 98.5% of all children; in the private sector 90.2% had received the third dose of the DTC/VPO-IPV vaccine, and in the public sector, 74.5%. The measles vaccination rate in the private sector was 82.5% compared with 64.4% in the public sector. The rates of coverage for antigens not included in the EPI varied from 50.8% to 74.2% in the private sector and from 6.2% to 32.5% in the public sector. The vaccine with the least coverage was the pneumococcal: only 3.2% and were vaccinated against this in the private sector and 0.8% in the public sector. The principal reasons for non-immunization were lack of financial resources (n = 283, 28.3%), in particular, for booster up vaccines and those recommended by the EPI, lack of information (n = 259, 25.9%), forgetfulness (n = 217, 21.7%), neglect (n = 113, 11.3%), sick child (n = 80, 8%), vaccine not available (n = 19, 1.9%), wrong information (n = 15, 1.5%), travel (n = 14, 1.4%), mother sick (n = 12, 1.2%) and lack of time (n = 18, 1.8%). Finally, the direct cost of good vaccination coverage for boosters was 42,245 FCFA (74 euros) in the public sector and 54,800 FCFA (84 euros) in the private sector.

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International audience; Africa is in the midst of an epidemiological transition characterized by an increase in degenerative illnesses, in particular cardiovascular disease, and a decrease in infectious illnesses. In this context it is of critical importance to develop simple and effective low-cost tools to identify subjects at high risk for cardiovascular events. Screening for subclavian artery stenosis (SAS) could provide a useful risk indicator. The prevalence of SAS in the general population over the age of 40 years in Gabon is 5.1 %, which is close to prevalence values observed in industrialized countries. Presence of SAS has been associated with hypertension (OR: 5.79, 95% CI: 2.21-15.2; p < 0.05) and male gender (OR 2.34, 95% CI: 1.13-4.83; p < 0.05). These data confirm the epidemiological shift towards cardiovascular diseases and suggest that screening for SAS could be useful to identify subjects at high risk for cardiovascular events who could benefit from preventive strategies.

Background Improving the understanding of childhood malarial anaemia may help in the design of appropriate management strategies. Methods A prospective observational study over a two-year period to assess the burden of anaemia and its relationship to Plasmodium falciparum infection and age was conducted in 8,195 febrile Gabonese children. Results The proportion of children with anaemia was 83.6% (n = 6830), higher in children between the ages of six and 23 months. Those under three years old were more likely to develop moderate to severe anaemia (68%). The prevalence of malaria was 42.7% and P. falciparum infection was more frequent in children aged 36–47 months (54.5%). The proportion of anaemic children increased with parasite density (p < 0.01). Most of infected children were moderately to severely anaemic (69.5%, p < 0.01). Infants aged from one to 11 months had a higher risk of developing severe malarial anaemia. In children over six years of age, anaemia occurrence was high (>60%), but was unrelated to P. falciparum parasitaemia. Conclusion Malaria is one of the main risk factors for childhood anaemia which represents a public health problem in Gabon. The risk of severe malarial anaemia increases up the age of three years. Efforts to improve strategies for controlling anaemia and malaria are needed.

International audience

ERMA; National audience

INTRODUCTION: Several neurological complications are associated with cerebral malaria (CM). However, few long-term data from childhood survivors have been published. METHODS: A cross-sectional study was carried out in Mali among children followed from 1999 to 2002 after serious and complicated malaria. Our aim was to evaluate the persistent neurological sequelae associated with CM. RESULTS: This study concerned 101 subjects who had had CM. Mean age was 5.6+/-3.6 years. Twenty-eight children presented persistent neurological sequelae (27.7p.cent). Among them eight (7.9p.cent) children had developed these sequelae just after CM and 20 (19.8p.cent) a few months later: headaches, mental retardation, speech delay, bucco-facial dyspraxia, diplegia and frontal syndrome (one case each), dystonia (two cases), epilepsy (five cases) and behavior and attention disorders (15 cases). CONCLUSIONS: In this study, we show that neurological signs due to CM can persist in the long run. Long-term follow-up and proper management after CM are essential.

International audience; PURPOSE: Cerebral malaria (CM) is suspected to be a potential cause of epilepsy in tropical areas. The purpose of this article was to evaluate the relationship between CM and epilepsy in Gabon. METHODS: A matched case-control study was carried out on a sample of subjects aged six months to 25 years and hospitalized between 1990 and 2004 in three hospitals in Libreville, Gabon. Cases were defined as patients suffering from epilepsy and confirmed by a neurologist. Controls were defined as patients without epilepsy. The exposure of interest was CM according to WHO criteria. RESULTS: In total, 296 cases and 296 controls were included. Of these, 36 (26 cases and 10 controls) had a CM history. The adjusted odds ratio (aOR) to develop epilepsy after CM was 3.9 [95% CI: 1.7-8.9], p

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.

International audience; Objectifs :Le paludisme cérébral (PC) est l’une des complications graves de l’infection palustre à Plasmodium falciparum. C’est une cause potentielle de survenue de l’épilepsie dans les pays tropicaux. Nous mettons ici en perspective les résultats de deux approches épidémiologiques différentes, réalisées l’une au Mali et l’autre au Gabon, dans le but de quantifier le lien entre cette parasitose et l’épilepsie séquellaire.Méthodes :Une étude exposés/non exposés a été réalisée dans une cohorte d’enfants maliens âgés de 6 mois à 15 ans et suivis au décours d’un paludisme grave. Une étude cas-témoins a été réalisée chez de jeunes sujets gabonais âgés 6 mois à 25 ans vus dans trois hôpitaux de Libreville sur une période de 15 ans (cas épileptiques et témoins non épileptiques). Dans ces études l’exposition principale était le PC défini selon les critères cliniques etbiologiques de l’OMS. L’épilepsie était définie selon la définition épidémiologique (ILAE) et confirmée par un neurologue.Résultats :Dans l’étude exposés/non exposés, nous avons comparé 101 enfants ayant eu un PC à 222 enfants avec paludisme non cérébral (PNC). Il y avait 9,4 fois plus de risque de développer l’épilepsie après un PC comparé à PNC (RR = 9,4 ; IC 95 % : 1,3-80,3 ; p = 0,02). Dans l’étude cas-témoins, 296 cas (épileptiques) et 296 témoins (non épileptiques) ont été comparés. Le risque de développer l’épilepsie avec un antécédent de PC était plus élevéchez les cas par rapport aux témoins : OR = 3,9 [IC 95 % : 1,7-8,9] p < 0,001.Conclusion :Le risque d’épilepsie séquellaire était significativement plus élevé après un PC. Le rôle possible de facteurs de confusion, en particulier celui des convulsions fébriles dues au PC, et le mécanisme physiopathologique précis restent à éclaircir.

International audience

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International audience

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