Molecular analyses of human rabies virus associated with encephalitis in two children in Gabon.

Rabies is a zoonotic neurological life-threatening neglected tropical disease present worldwide, and Gabon is listed as an endemic country. However, despite strong clinical suspicion in humans and molecular confirmation of rabies virus (RABV) infections in dogs for several decades, no molecularly confirmed human case in Gabon has ever been reported. In this study, we describe two cases of human rabies and provide the first molecular diagnostic report on suspected human rabies cases in Gabon. Our results showed that the RABVs isolated from the patients are closely related to other RABV strains belonging to the African 1A subclade in the Cosmopolitan lineage isolated more than 20 years ago from Gabonese dog brains, suggesting that only this species circulates in the country. Because both patients had a history of dog bites a few weeks before symptom onset and the main causative agent of human rabies worldwide is dog-associated RABV, we conclude that dogs are likely to be the source of human infection in this study.

Aspects épidemiologiques et thérapeutiques de l'anémie néonatale au centre hospitalo-universitaire d'Angondje- Gabon

Introduction : l'anémie néonatale est une pathologie fréquemment rencontrée dans les services de néonatologie. Sa prévalence est mal définie dans la littérature en général, et en Afrique en particulier. Objectif : étudier les caractéristiques épidémiologiques et thérapeutiques de l'anémie néonatale au Centre Hospitalo-Universitaire d'Angondjé. Patients et méthodes : il s'agit d'une étude rétrospective qui s'est déroulée au Centre Hospitalo-Universitaire d'Angondjé, sur une période de 4 ans allant de 2012 à 2016. Tous les dossiers de nouveau-nés hospitalisés pendant cette période et ayant présenté une anémie (taux d'hémoglobine ˂13g/dl) ont été inclus. Résultat : 105 cas d'anémie néonatale avait été enregistré parmi les 658 hospitalisations soit une prévalence de 16%. Les nouveau-nés prématurés représentaient 64%. A l'admission, 45,7% de nouveau-nés présentaient d'emblée une anémie avec un taux moyen d'hémoglobine de 10,8g/dl et 54,3% étaient non anémiés à l'admission avec une hémoglobine moyenne de 15,2g/dl±2,5. L'infection néonatale (56,3%), l'anoxie périnatale (8,5%), la prématurité, les prélèvements répétés représentent les facteurs de risque associés à la survenue de l'anémie. La transfusion de globules rouges était la base thérapeutique dans 69,1% de cas. Le taux de décès lié à l'anémie était de 9,6%. Conclusion : l'anémie chez le nouveau-né est un facteur de risque de mortalité néonatale en Afrique, et dans le monde. La régression de ce trouble passe par la prévention

[Immunization coverage of children aged 0 to 5 years in Libreville (Gabon)]. / Étude de la couverture vaccinale chez les enfants de 0 à 5 ans à Libreville (Gabon).

UNLABELLED: 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.

Impact of Plasmodium falciparum infection on the frequency of moderate to severe anaemia in children below 10 years of age in Gabon.

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.

Self-reactivities to the non-erythroid alpha spectrin correlate with cerebral malaria in Gabonese children.

BACKGROUND: Hypergammaglobulinemia and polyclonal B-cell activation commonly occur in Plasmodium sp. infections. Some of the antibodies produced recognize self-components and are correlated with disease severity in P. falciparum malaria. However, it is not known whether some self-reactive antibodies produced during P. falciparum infection contribute to the events leading to cerebral malaria (CM). We show here a correlation between self-antibody responses to a human brain protein and high levels of circulating TNF alpha (TNFalpha), with the manifestation of CM in Gabonese children. METHODOLOGY: To study the role of self-reactive antibodies associated to the development of P. falciparum cerebral malaria, we used a combination of quantitative immunoblotting and multivariate analysis to analyse correlation between the reactivity of circulating IgG with a human brain protein extract and TNFalpha concentrations in cohorts of uninfected controls (UI) and P. falciparum-infected Gabonese children developing uncomplicated malaria (UM), severe non-cerebral malaria (SNCM), or CM. RESULTS/CONCLUSION: The repertoire of brain antigens recognized by plasma IgGs was more diverse in infected than in UI individuals. Anti-brain reactivity was significantly higher in the CM group than in the UM and SNCM groups. IgG self-reactivity to brain antigens was also correlated with plasma IgG levels and age. We found that 90% of CM patients displayed reactivity to a high-molecular mass band containing the spectrin non-erythroid alpha chain. Reactivity with this band was correlated with high TNFalpha concentrations in CM patients. These results strongly suggest that an antibody response to brain antigens induced by P. falciparum infection may be associated with pathogenic mechanisms in patients developing CM.

Cerebral malaria and sequelar epilepsy: first matched case-control study in Gabon.

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<0.001. Additional risk factors were identified: family history of epilepsy: aOR=6.0 [95% CI: 2.6-14.1], p<0.0001, and febrile convulsions: aOR=9.2 [95% CI 4.0-21.1], p<0.0001. CONCLUSIONS: This first case-control study on that issue suggests that epilepsy-related CM is an underrecognized problem. It emphasizes the need for further studies to better evaluate the role of convulsions during CM.