Rage humaine et itinéraire médical au Niger: A propos d’un cas confirmé par RT- qPCR en 2019: Human rabies and the medical route in Niger: About a case confirmed by RT- qPCR in 2019

La rage est une zoonose virale, endémique en Afrique. Elle a une létalité de 100%. Cette étude rapporte le premier cas de rage humaine confirmé par RT-qPCR au Niger. En Octobre 2019, un patient de 22 ans avait consulté pour des difficultés à manger, à boire et une agitation. Il fut traité pour un paludisme. Devant la persistance des signes, il fut transféré à l’hôpital National de Niamey. Un interrogatoire poussé a révélé une notion de morsure par un chien. A l’examen, le patient était agité, agressif et présentait une paralysie de la jambe gauche. Ses yeux étaient congestionnés et il avait une hyper sialorrhée. Il fut suspecté de rage et fut isolé et pris en charge et la procédure «One Health» a été déclenchée. Il a été mis sous tranquillisant. Une biopsie nucale et un prélèvement de salive furent réalisés et envoyées à l’Institut Pasteur de Dakar. La rage fut confirmée par RT-qPCR. L’observation et l’analyse du parcours médical de ce cas de rage humaine, et des facteurs de risque ont permis de mettre en évidence des insuffisances dans le suivi des chiens, les connaissances, les attitudes et les pratiques sur la rage. Des insuffisances dans la surveillance épidémiologique et microbiologique et dans la gestion des cas ont également été notées. Ces observations confirment les résultats des outils d’évaluations (SARE et PVS) du réseau de surveillance de la rage canine au Niger. Rabies is a viral zoonosis, endemic in Africa. It is 100% lethal. This study reports the first case of human rabies confirmed by RT-PCR in Niger. In October 2019, a 22-year-old patient had consulted for difficulty eating, drinking and restlessness. He was treated for malaria. Faced with the persistence of the signs, he was transferred to the Niamey National Hospital. A thorough interrogation revealed a notion of dog bite. On examination, the patient was restless, aggressive and presented a left leg paralysis. His eyes were congested and he had a hyper sialorrhea. He was suspected for rabies, isolated, and treated and the “One Health” procedure was initiated. He received a tranquilizer. The nuchal biopsy and saliva sample collection were performed and sent to the Pasteur Institute in Dakar. Rabies was confirmed by RT q PCR. The observation and analysis of the medical history of this case of human rabies, and the risk factors made it possible to highlight flaws in the monitoring of dogs, knowledge, attitudes and practices on rabies, microbiological and epidemiological surveillance, and finally case management. It also identified the reasons for the underreporting of rabies cases. These observations confirm the results of the assessment tools (SARE and PVS) of the canine rabies surveillance network in Niger

Influence des paramètres climatiques sur l’incidence de la COVID-19 de mars 2020 à décembre 2022 dans la région de Niamey au Niger

Introduction : La maladie à coronavirus 2019 (COVID-19) est une maladie infectieuse due au nouveau coronavirus. Son émergence est un enjeu de santé publique mondial. Le rôle des facteurs climatiques dans sa transmission n’est pas déterminé avec précision. Objectif : Cette étude analyse la corrélation entre les paramètres climatiques (température, humidité relative, durée d’ensoleillement, vitesse du vent) et la dynamique de la COVID-19.  Méthodologie : C’est une étude rétrospective, analytique, utilisant les données épidémiologiques de la COVID 19 (nombre quotidien de cas confirmés et des décès) de mars 2020 à décembre 2022. Ils ont été recueillis à la Direction de la Surveillance et la Riposte aux Epidémies (DSRE). Les données climatiques ont été recueillies à la Direction de la Météorologie Nationale (DMN). La méthode statistique utilisée est le coefficient de corrélation ‘’r’’ entre les variables climatiques et morbi-mortalité de la COVID-19. Résultats : L’analyse uni variée montre que le nombre de cas le plus élevé était observé en septembre. L’humidité relative minimale la plus élevée fut observée en août. L’analyse multivariée révèle une corrélation forte et positive entre la vitesse moyenne du vent et la morbidité  (r= 0,14). La vitesse maximale du vent  (r= 0,13), la vitesse minimale du vent (r= 0,15) influencent la survenue des nouveaux cas de la COVID-19. Conclusion : L’humidité relative a impact sur la morbi-mortalité, par opposition à la température. Le plus grand nombre des cas intervient en novembre, décembre et janvier, les mois durant lesquelles les températures sont plus basses. Ces informations sont utiles pour planifier et soutenir la lutte contre la COVID-19.   Introduction: Coronavirus 2019 (COVID-19) is an infectious disease caused by a new coronavirus. Its emergence is a global public health issue. The role of climatic factors in its transmission is not precisely determined. Objective: This study analyzes the correlation between climatic parameters (temperature, relative humidity, sunshine duration, wind speed) and the dynamics of COVID-19. Methodology: This is a retrospective, analytical study using COVID 19 epidemiological data (daily number of confirmed cases and deaths) from March 2020 to December 2022. They were collected at the Direction de la Surveillance et la Riposte aux Epidémies (DSRE). Climatic data were collected from the Direction de la Météorologie Nationale (DMN). The statistical method used was the "r" correlation coefficient between the COVID-19 climate and morbidity-mortality variables. Results: Univariate analysis shows that the highest number of cases occurred in September. Minimum relative humidity was highest in August. Multivariate analysis revealed a strong, positive correlation between mean wind speed and morbidity (r= 0.14). Maximum wind speed (r= 0.13) and minimum wind speed (r= 0.15) influenced the occurrence of new cases of COVID-19. Conclusion: Relative humidity has an impact on morbidity and mortality, as opposed to temperature. The greatest number of cases occurs in November, December and January, the months when temperatures are lowest. This information is useful for planning and supporting the fight against COVID-19

Epidemiological, clinical and biological features of malaria among children in Niamey, Niger

BACKGROUND: Malaria takes a heavy toll in Niger, one of the world's poorest countries. Previous evaluations conducted in the context of the strategy for the Integrated Management of Childhood Illness, showed that 84% of severe malaria cases and 64 % of ordinary cases are not correctly managed. The aim of this survey was to describe epidemiological, clinical and biological features of malaria among <5 year-old children in the paediatric department of the National Hospital of Niamey, Niger's main referral hospital. METHODS: The study was performed in 2003 during the rainy season from July 25(th )to October 25(th). Microscopic diagnosis of malaria, complete blood cell counts and measurement of glycaemia were performed in compliance with the routine procedure of the laboratory. Epidemiological data was collected through interviews with mothers. RESULTS: 256 children aged 3–60 months were included in the study. Anthropometrics and epidemiological data were typical of a very underprivileged population: 58% of the children were suffering from malnutrition and all were from poor families. Diagnosis of malaria was confirmed by microscopy in 52% of the cases. Clinical symptoms upon admission were non-specific, but there was a significant combination between a positive thick blood smear and neurological symptoms, and between a positive thick blood smear and splenomegaly. Thrombopaenia was also statistically more frequent among confirmed cases of malaria. The prevalence of severe malaria was 86%, including cases of severe anaemia among < 2 year-old children and neurological forms after 2 years of age. Overall mortality was 20% among confirmed cases and 21% among severe cases. CONCLUSIONS: The study confirmed that malaria was a major burden for the National Hospital of Niamey. Children hospitalized for malaria had an underprivileged background. Two distinctive features were the prevalence of severe malaria and a high mortality rate. Medical and non-medical underlying factors which may explain such a situation are discussed

Controlling Schistosomiasis: Significant Decrease of Anaemia Prevalence One Year after a Single Dose of Praziquantel in Nigerien Schoolchildren

The World Health Organization's recommendation for the control of urinary schistosomiasis is to reduce morbidity by reducing the prevalence of heavy infections. In Niger, where urinary schistosomiasis is endemic along the Niger River valley and in proximity to ponds, a national control programme for schistosomiasis and soil-transmitted helminth was launched in 2004 with the financial support of the Gates Foundation through the Schistosomiasis Control Initiative. In the framework of the monitoring and evaluation of the control programme, a follow-up of school children took place in eight sentinel sites. The aim of this study was to assess the evolution of Schistosoma haematobium infection and associated morbidity after a single-dose administration of praziquantel and albendazole. Before treatment, the overall prevalence of S. heamatobium infection was 75.4% and anaemia (haemoglobin <11.5 g/dl) was present in 61.6% of the study sample. One year after a single-dose praziquantel treatment (administered by dose-pole) co-administered with albendazole (400 mg single dose) for de-worming, all morbidity markers of the infection decreased significantly. This study shows how a schistosomiasis control programme can benefit populations by improving their health status

Prevalence of Mutations in the \u3ci\u3ePfdhfr\u3c/i\u3e, \u3ci\u3ePfdhps\u3c/i\u3e, and \u3ci\u3ePfmdr1\u3c/i\u3e Genes of Malarial Parasites Isolated from Symptomatic Patients in Dogondoutchi, Niger

The effectiveness of artemisinin-based combination therapies (ACTs) depends not only on that of artemisinin but also on that of partner molecules. This study aims to evaluate the prevalence of mutations in the Pfdhfr, Pfdhps, and Pfmdr1 genes from isolates collected during a clinical study. Plasmodium genomic DNA samples extracted from symptomatic malaria patients from Dogondoutchi, Niger, were sequenced by the Sanger method to determine mutations in the Pfdhfr (codons 51, 59, 108, and 164), Pfdhps (codons 436, 437, 540, 581, and 613), and Pfmdr1 (codons 86, 184, 1034, and 1246) genes. One hundred fifty-five (155) pre-treatment samples were sequenced for the Pfdhfr, Pfdhps, and Pfmdr1 genes. A high prevalence of mutations in the Pfdhfr gene was observed at the level of the N51I (84.97%), C59R (92.62%), and S108N (97.39%) codons. The key K540E mutation in the Pfdhps gene was not observed. Only one isolate was found to harbor a mutation at codon I431V. The most common mutation on the Pfmdr1 gene was Y184F in 71.43% of the mutations found, followed by N86Y in 10.20%. The triple-mutant haplotype N51I/C59R/S108N (IRN) was detected in 97% of the samples. Single-mutant (ICS and NCN) and double-mutant (IRS, NRN, and ICN) haplotypes were prevalent at 97% and 95%, respectively. Double-mutant haplotypes of the Pfdhps (581 and 613) and Pfmdr (86 and 184) were found in 3% and 25.45% of the isolates studied, respectively. The study focused on the molecular analysis of the sequencing of the Pfdhfr, Pfdhps, and Pfmdr1 genes. Although a high prevalence of mutations in the Pfdhfr gene have been observed, there is a lack of sulfadoxine pyrimethamine resistance. There is a high prevalence of mutation in the Pfmdr184 codon associated with resistance to amodiaquine. These data will be used by Niger’s National Malaria Control Program to better monitor the resistance of Plasmodium to partner molecules in artemisinin-based combination therapies

Field-based evidence of fast and global increase of Plasmodium falciparum drug-resistance by DNA-microarrays and PCR/RFLP in Niger

<p>Abstract</p> <p>Background</p> <p>Over the last years, significant progress has been made in the comprehension of the molecular mechanism of malaria resistance to drugs. Together with <it>in vivo </it>tests, the molecular monitoring is now part of the survey strategy of the <it>Plasmodium </it>sensitivity. Currently, DNA-microarray analysis allows the simultaneous study of many single nucleotide polymorphisms (SNP) of <it>Plasmodium </it>isolates. In December 2005, the International Federation of the Red Cross distributed two million three hundred thousand long-lasting insecticide nets to pregnant women and mothers of under five years children in the whole Niger. Then, Niger adopted artemisinin-based combination therapy as first-line treatment.</p> <p>Methods</p> <p>Thirty four SNPs of <it>pfcrt, pfdhfr, pfdhps, pfmdr </it>and <it>pfATPase </it>were analysed by DNA-microarray and PCR/RFLP in two villages – Zindarou and Banizoumbou – with different durations of malaria transmission. The main objective of the study was to measure the dynamics <it>of Plasmodium falciparum </it>resistant strains and associated factors.</p> <p>Results</p> <p>This study shows a global and clear increase of the drug-resistance associated molecular markers frequencies during a relatively short-time period of four years. Markers associated with resistance to chloroquine and sulphonamids were more frequently found in the short transmission zone than in the long transmission one. The <it>pfcrt76T </it>mutation is significantly more present at Banizoumbou than Zindarou (38.3% vs 25.2%, p = 0.013).</p> <p>This work allowed the screening of several field strains for five SNPs of <it>PfATPase6 </it>gene. The <it>pfATPase6S769N</it>, candidate mutation of resistance to artemisinin was not found. However the <it>pfATPsaeA623E </it>mutation was found in 4.7% of samples.</p> <p>Conclusion</p> <p>A significant increase of several SNPs frequencies was highlighted over a four-year period. The polymorphism of five <it>PfATPase6 </it>gene SNPs was described. The global, large and fast increase of the molecular resistance is discussed in the context of current changes of health policy and malaria control in Niger.</p

Polymorphism of PfATPase in Niger: detection of three new point mutations

International audienceBackgroundPlasmodium falciparum resistance to drugs remains a major public health issue in Niger. The therapeutic failure index for chloroquine and sulphadoxine-pyrimethamine are, respectively 20% and 21.9%. In December 2005, the National Malaria Control Programme promoted the use of artemisinin combination therapy (ACT) as first-line treatment of the uncomplicated malaria cases. Recently, studies have shown a relationship between the SERCA PfATPase6 gene and artemisinin efficacy, and pointed it out as a potential molecular marker for resistance. The goal of this work was to describe the baseline polymorphism of PfATPase6 gene in Niger, at a time when the national implementation of the ACT policy had just begun.Materials and methodsThe DNA polymorphism of the PfATPase6 gene of 87 P. falciparum samples from Niger was analysed by sequencing. The links between the mutation occurrence and environment and human host factors were tested by bivariate analysis.ResultsThe P. falciparum PfATPase6 gene presented polymorphisms at codons 537, 561, 569, 630, 639, 716 levels. All the mutations found were rare, except the PfATPaseN569K found in 17.2% of samples. No associated factor has been observed.ConclusionThe P. falciparum PfATPase gene is polymorphic at the 569 codon. As ACT is getting more and more used, the PfATPase6 gene polymorphism needs to be monitored in association with phenotypic – in vivo and/or in vitro – drug efficacy tests

Linking environmental variability to village-scale malaria transmission using a simple immunity model

International audienc

Transfusional Malaria and Associated Factors at the National Blood Transfusion Center of Niamey-Niger

Summary. Problem. Transfusional malaria is an accidental transmission of Plasmodium via a blood transfusion. Its magnitude is underestimated and very little data on the assessment of this risk are available in Niger. Objective. This study aimed to determine the prevalence of plasmodial infection of blood bags at the National Blood Transfusion Center of Niamey (NBTC). Methodology. A cross-sectional study to diagnose Plasmodium infection by microscopy and Rapid Diagnostic Test (RDT) was carried out during the rainy season (September to November 2015). Blood grouping was performed by the BETH-VINCENT technique. Results. One thousand three hundred and fifty-seven (1357) blood bags were collected. One hundred and fifty-seven (11.6%) of the donors were infected with Plasmodium by microscopy and 2.4% (9/369) by rapid diagnostic test. All infections were with P. falciparum (100%). The mean parasite density was 197 parasites/μL (SD=281; [80: 2000]). There were no significant differences in infection prevalence between the ABO blood groups (p=0.3) or the rhesus positivity (p=08). There is also no significant difference in temporal (p=0.1) and spatial (p=0.6) distribution. Conclusion. The transmission of transfusional malaria during the rainy season is a fact in Niger. Such risks were independent of the ABO blood type and positivity for the rhesus antigen. Pretransfusion diagnosis or posttransfusion therapy should be instituted to prevent it