Mouhamadou Diagana

Japanese encephalitis revisited

Japanese encephalitis (JE) is a major public health problem in Southeast Asia with around 50,000 cases and 10,000 deaths per year affecting essentially children below 10 years of age. The JE virus has shown a tendency to extend to other geographic regions. JE may cause severe encephalitis and survivors are frequently left with serious neurological lesions. In the absence of an effective antiviral treatment, prevention constitutes the best defense against this disease. Besides the implementation of vector control, immunization by vaccination is available. Vector control is expensive and difficult to implement on a large scale, leaving vaccination as the best means for mass campaigns. Recent progress in the development of live attenuated vaccines has given hope of an effective vaccine, which is both easy to use and inexpensive for large scale programs.

Juvenile and adult-onset ALS/MND among Africans: incidence, phenotype, survival: A review

Abstract Aim: We reviewed the epidemiology of ALS among subjects of African origin, considering incidence, phenotype and prognosis. Methods: We searched Medline, Scopus, Science direct, Bibliothèque Virtuelle de Neurologie Africaine (BVNA), (http://www-ient.unilim.fr/) and African journal OnLine databases using the following search terms “amyotrophic lateral sclerosis (ALS)”, “motor neuron disease (MND)” or “Charcot disease”, in combination with “Africa”, “ethnic groups”, “blacks” or “epidemiology”. Of 1264 references examined, 35 were included in this review. Results and discussion: Among the 35 references, 19 studies were performed in the African continent and dealt with MND/ALS; four other studies focused on ALS-like syndromes; finally, 12 studies were not performed in Africa but focused on either incidence and mortality or survival of ALS in subjects of African origin. Several characteristics of ALS among Africans or subjects of African origin were identified: (i) lower incidence rates among people of African origin living in western countries, (ii) higher incidence of classic ALS among men, (iii) presence of juvenile form, (iv) younger age at onset of classic ALS. We cannot draw firm conclusions about (i) the prognosis in African ALS patients, (ii) prognostic factors, (iii) genetic or behavioral factors affecting incidence or clinical phenotype. Conclusion: Further multicenter prospective studies with homogeneous methodological approaches need to be performed in Africa to clarify the situation.

Clinical features and prognosis of amyotrophic lateral sclerosis in Africa: the TROPALS study

Objective We describe and compare the sociodemographic and clinical features, treatments, and prognoses and survival times of patients with amyotrophic lateral sclerosis (ALS) in Africa. Methodology We conducted a multicentre, hospital-based cohort study in Africa. Patients with ALS diagnosed in the neurology departments of participating hospitals from 2005 to 2017 were included. Subgroup analysis was performed by subcontinent. Survival analyses were conducted using the Cox proportional hazards model. Results Nine centres from eight African countries participated. A total of 185 patients with ALS were included: 114 from Northern Africa, 41 from Western Africa and 30 from Southern Africa. A male predominance (male to female ratio 2.9) was evident. The median age at onset was 53.0 years (IQR 44.5–64.0 years). The onset was bulbar in 22.7%. Only 47 patients (26.3%) received riluzole, mainly in Northern and Western Africa. The median survival from the time of diagnosis was 14.0 months (95% CI 10.7 to 17.2 months). The median survival was longer in Northern Africa (19.0 months, 95% CI 10.8 to 27.2 months) than in Western (4.0 months, 95% CI 0.8 to 7.1 months) and Southern (11.0 months, 95% CI 5.6 to 16.4 months) Africa (Breslow test, p<0.0001). Both subcontinental location and riluzole treatment independently affected survival. Conclusion More African patients with ALS were male and younger and exhibited a lower proportion of bulbar onset compared with patients with ALS from Western nations. Survival was consistent with that in Western registers but far shorter than what would be expected for young patients with ALS. The research improves our understanding of the disease in Africa.

Preliminary report of Tropals study — A survey of amyotrophic lateral sclerosis in Africa

Background: Epidemiological studies of Amyotrophic Lateral Sclerosis (ALS) in the tropics are rare and their methodologies, heterogeneous. Many questions arise as regards the characteristics of this disease in the tropics, especially in Africa.Objective: Describe sociodemographical and clinical characteristics of ALS patients diagnosed in Africa.Patients and methods/material and methods: TROPALS (http://www.tropals.unilim.fr/) is a multicentre observational cohort study. A shared methodology and an online data base that allows centers to collect data in a standardized and homogeneous way.Results: 40 patients have been included to date in 5 centers (Benin, Mauritania, Senegal, Togo, Tunisia), 3 other centers are open (Burkina Faso, Gabon, Mali) and 6 are about to be open.Mean age at diagnosis was 51.9 ± 13.5 years (2 cases less than 25 years), male/female sex ratio was 2.4.First symptoms were mostly spinal (72.5%) and 80% (n = 32/40) of patients had Electroneuromyography for diagnosis purpose. At this time mean ALS FRS R was 32.1 ± 10.5 and 75% of patients presented atypical symptoms (mostly dysautonomic or sphincter problems).After diagnosis, 97.4% of patients were prescribed an occidental treatment: Rilutek® (n = 12), physiotherapy (n = 17), or symptomatic treatment (n = 12). 21.6% of patients used a “traditional treatment” based on infusion-decoction for 2 of them and of unknown type for 6 patients.Conclusion: More inclusions are needed to produce precise estimations. Follow-up data are currently being collected. Tropals study will allow us to improve the description of ALS characteristic prognosis of patients and comprehension of the disease in this continent.