Dynamics of germs responsible for acute bacterial meningitis in Burkina Faso in the last ten years (2005-2014)

The aim of this study was to analyze ten (10) years of epidemiological surveillance data of meningitis in Burkina Faso for high risk germs patterns identification in order to contribute to the strengthening of prevention strategies.A retrospective study of the past decade (2005- 2014) of cases of acute bacterial meningitis occurred in the thirteen health regions, collected through epidemiological surveillance data meningitis in Burkina Faso. From a total of 88 057 suspected cases of acute bacterial meningitis, we recorded 9134 deaths. From the laboratory confirmed cases, the identified germs were as follows: 56.79% of Neisseria meningitidis, 41.09% of Streptococcus pneumoniae and 2.13% of Haemophilus influenzae. Among the meningococcus isolated, we observed the following distribution: 23.11% of NmA, 58.84% of NmW and 18% of NmX.Mortality associated with acute bacterial meningitis remains still high in Burkina Faso despite the complete disappearance of NmA since 2012, after the conjugate vaccine A (MenAfriVac) has been introduced in this country. However the emergence of NmX, the reemergence of NmW and the persistence of high prevalence of Streptococcus pneumoniae are a major concern in the fight against meningitis in Burkina Faso. So, it is necessary, in addition to the strengthening of surveillance, diagnosis and case management to develop and make available and accessible a conjugate trivalent vaccine against NmA the NmX and NmW serogroups.Keywords: meningococcal meningitis, W and X serogroups, Streptococcus pneumoniae, MenAfriVa

Etiology and risk factors for meningitis during an outbreak in Batié Health District, Burkina Faso, January-March 2016

Introduction: On 16 March 2016, Batié Health District notified the Burkina Faso Ministry of Health Surveillance unit of 12 suspected cases of meningitis. During the same period, Batié´s neighboring districts in Côte d'Ivoire and Ghana were experiencing a meningitis epidemic. We investigated to establish the etiology and risk factors for the disease and to recommend prevention and control measures. Methods: We conducted unmatched case control study. A case was any person living in Batié with fever (temp. ≥ 38.5°C) and any of the following: neck stiffness, neurological disorder, bulging fontanelle, convulsion during January to April 2016 with cerebrospinal fluid (CSF) positive to PCR. Controls were non sick household members, neighbors or friends to the cases. We analyzed the investigation and laboratory records. We included all confirmed cases and two neighborhood controls per case. We used a standard questionnaire to collect data. We analyzed data by Epi info 7 and calculated odds ratio (ORs),adjusted odds ratios (AOR) and 95% confidence interval. We proceeded to univariate, bivariate, multivariate and logistic regression analysis. Results: We interviewed 93 participants including 31 meningitis cases and 62 controls. The median age of cases was 8 years old [2 months-55 years] and 6.5 years old [5 months-51 years] for controls. Streptococcus pneumoniae 16(51.61%), Neisseria meningitidis W 14(45.16%) and Haemophilus influenzae b 1(3.23%) were the identified germs. The independent risk factors identified were travel to meningitis affected areas (Adjusted odd ratio(AOR)=12[2.3-60],p=0.0029); >5 persons sharing bedroom (AOR=5.7[1.5-22],p=0.012) and rhinopharyngitis (AOR=26[1.8-380],p=0.017). Conclusion: Streptococcus pneumoniae and Neisseria meningitidis W caused the outbreak in Batié. The risk factors were overcrowding, travel to affected areas, and rhinopharyngitis. We recommended reactive vaccination against Neisseria meningitidis W, limited travel to affected areas and ventilation of rooms

Ampleur de la dengue dans la ville de Ouagadougou, Burkina-Faso, 2016: Magnitude of dengue fever in the city of Ouagadougou, Burkina-Faso, 2016

Introduction: En Octobre 2016, le Burkina Faso a connu une flambée de cas de dengue dont l’ampleur est peu connue. Aussi aucune étude n’a été réalisée durant les dix dernières années, donnant lieu à un manque d’information actualisée sur sa prévalence et son incidence. Cette étude avait pour objectif de déterminer l’ampleur de la dengue à Ouagadougou et le type de virus circulant. Méthodes: Nous avons mené une étude transversale sur les cas de dengue enregistrés dans les formations sanitaires (FS) de la ville de Ouagadougou du 1er août au 31 décembre 2016. Un cas de dengue était défini comme toute personne résident dans la ville de Ouagadougou présentant une maladie fébrile aiguë (2-7 jours), avec au moins deux des symptômes suivants : céphalées, douleur rétro-orbitale, myalgie, arthralgie, éruption cutanée, manifestations hémorragiques, syndrome de choc et un test biologique positif à la PCR ou avec TDR-Dengue positif ayant un lien épidémiologique avec un cas confirmé. Nous avons réalisé une recherche active des cas à travers une revue documentaire des registres de laboratoire, consultation et/ou d’hospitalisation des FS, Une fiche de collecte a été utilisée pour recueillir les caractéristiques sociodémographiques, cliniques, biologiques des cas. Résultats: Au total, 5094 cas de dengue ont été enregistrés dans les FS. L’âge médian était de 27 ans avec un intervalle interquartile de 16 à 37 ans. Quinze cas (51,72%) ont été testés positifs à la PCR dont 10 (66,67%) au DENV2 et 5 (33,33%) au DENV3. Parmi les cas, 2569 (50,76%) étaient de sexe féminin et 1494 (28,16%) cas avaient été hospitalisés. Sur les cas recensés, 73% avaient été notifiés par les structures privées et 3174 (88,88%) étaient des éleves/étudiants ou fonctionnaires ou commerçants. Le taux d’attaque global était de 201 cas (5094/2532311) pour 100000 habitants. Le taux de létalité était de 35/5094 (0,69%). Conclusion: Le taux d’attaque global de la dengue en 2016 était de 201 cas pour 100000 habitants. La dengue touchait plus les adultes jeunes surtout les élèves/étudiants et les fonctionnaires et était causée par les types 2 et 3. Les cas étaient plus notifiés par les structures privées. Une surveillance hebdomadaire associée à une surveil-lance sentinelle et la sensibilisation de la population sur la dengue contribueraient à endiguer ce fléau au Burki-na Faso. Background: In October 2016, Burkina Faso experienced an outbreak of dengue fever that the magnitude is little known. Also, no studies have been performed in the past ten years, giving rise to a lack of updated information on its prevalence and incidence. We conducted an investigation to determine the magnitude of dengue fever in Ouagadougou’s city and the type of virus circulating. Methods: We conducted a cross-sectional study on the cases of dengue recorded in health facilities (HF) in Ouagadougou’s city from August 1st to December 31st, 2016. We defined a case of dengue as any person resident in the city of Ouagadougou with acute febrile illness (2-7days), with at least two of the following symptoms (headache, retro-orbital pain, myalgia, arthralgia, rash, hemorrhagic manifestations, shock syndrome) and a positive PCR test or with dengue-RDT positive, having an epidemiological link with a confirmed case. We carried out an active search for cases through a documentary review of laboratory, consultation and/or hospitalization registers of HF, used a file to collect the socio-demographic, clinical and biological characteristics of the cases. Results: A total of 5094 cases of dengue fever were recorded in the HF. The median age was 27 years with an interquartile range of 16 to 37 years old. Fifteen (51.72%) cases tested positive with PCR including 10(66.67%) for DENV2 and 5(33.33%) for DENV3. Among the cases, 2,569(50.76%) were female and 1,494(28.16%) cases were hospitalized. Of the cases listed, 73% were notified by private’s hospitals and 3,174 (88.88%) were pupils/students or civil servants or traders. The overall attack rate was 201 cases (5094/2532311) per 100,000 populations. The case fatality rate was 35/5094 (0.69%). Conclusion: The overall dengue attack rate in 2016 was 201 cases per 100,000 populations. Dengue more affected young adults especially the pupils/students or civil servants and was caused by types 2 and 3. The cases were more notified by the private hospitals. We recommend weekly surveillance, sentinel surveillance and public awareness of dengue fever

Serogroup W Meningitis Outbreak at the Subdistrict Level, Burkina Faso, 2012

In 2012, Neisseria meningitidis serogroup W caused a widespread meningitis epidemic in Burkina Faso. We describe the dynamic of the epidemic at the subdistrict level. Disease detection at this scale allows for a timelier response, which is critical in the new epidemiologic landscape created in Africa by the N. meningitidis A conjugate vaccine

Initial validation of a simulation model for estimating the impact of serogroup A Neisseria meningitidis vaccination in the African meningitis belt.

We previously developed a mathematical simulation of serogroup A Neisseria meningitidis (NmA) transmission in Burkina Faso, with the goal of forecasting the relative benefit of different vaccination programs. Here, we revisit key structural assumptions of the model by comparing how accurately the different assumptions reproduce observed NmA trends following vaccine introduction. A priori, we updated several of the model's parameters based on recently published studies. We simulated NmA disease under different assumptions about duration of vaccine-induced protection (including the possibility that vaccine-induced protection may last longer than natural immunity). We compared simulated and observed case counts from 2011-2017. We then used the best-fit model to forecast the impact of different vaccination strategies. Our updated model, with the assumption that vaccine-induced immunity lasts longer than immunity following NmA colonization, was able to reproduce observed trends in NmA disease. The updated model predicts that, following a mass campaign among persons 1-29 years of age, either routine immunization of 9 month-old children or periodic mini-campaigns among children 1-4 years of age will lead to sustained control of epidemic NmA in Burkina Faso. This validated model can help public health officials set policies for meningococcal vaccination in Africa

Neisseria meningitidis Serogroup W, Burkina Faso, 2012

In 2010, Burkina Faso became the first country to introduce meningococcal serogroup A conjugate vaccine (PsA-TT). During 2012, Burkina Faso reported increases in Neisseria meningitidis serogroup W, raising questions about whether these cases were a natural increase in disease or resulted from serogroup replacement after PsA-TT introduction. We analyzed national surveillance data to describe the epidemiology of serogroup W and genotyped 61 serogroup W isolates. In 2012, a total of 5,807 meningitis cases were reported through enhanced surveillance, of which 2,353 (41%) were laboratory confirmed. The predominant organism identified was N. meningitidis serogroup W (62%), and all serogroup W isolates characterized belonged to clonal complex 11. Although additional years of data are needed before we can understand the epidemiology of serogroup W after PsA–TT introduction, these data suggest that serogroup W will remain a major cause of sporadic disease and has epidemic potential, underscoring the need to maintain high-quality case-based meningitis surveillance after PsA–TT introduction. Download MP3  Length: 1:4