Detection of influenza B viruses with reduced sensitivity to neuraminidase inhibitor in Morocco during 2014/15 season.

We monitored phenotypic and genotypic susceptibility of influenza viruses circulating in Morocco during 2014-2015 to oseltamivir and zanamivir. Throat and nasal swab specimens were collected from outpatients (with influenza-like illness) and inpatients (with severe acute respiratory illness) and tested for influenza viruses using real-time reverse transcription polymerase chain reaction. Positive samples were inoculated in MDCK cells and virus phenotypic susceptibility to neuraminidase inhibitors (NAIs) was assessed using fluorescent NA inhibition. Of 440 specimens, 135 were positive for influenza B Yamagata-like virus, 38 were A(H1N1)pdm09 and 25 were A(H3N2). Sixty influenza B viruses isolated from MDCK cells showed no significant resistance to NAIs. However, two of these strains, B/Morocco/176H/2015 and B/Morocco/CP10/2015, showed reduced susceptibility to oseltamivir. The two influenza B viruses with reduced susceptibility to oseltamivir show that ongoing NAI susceptibility surveillance is essential.

Circulation of Respiratory Syncytial Virus in Morocco during 2014-2016: Findings from a sentinel-based virological surveillance system for influenza.

Respiratory syncytial virus (RSV) is a leading cause of mortality and morbidity in young infants, little was known on its circulation types and patterns in Morocco. We conducted a prospective study using sentinel-based influenza surveillance to detect RSV by real time PCR in patients with acute respiratory infections, enrolled during two seasons (2014/15, 2015/16). During September 2014-April 2016, we obtained 1450 specimens, of which 267(18.4%) tested positive for RSV. The proportion of positive RSV infection was higher in patients hospitalized with acute respiratory infection compared to those with mild symptoms in out-patient clinics. The proportion of RSV infection was highest in children aged 0-6 months (45%; P < 0.001). Higher positivity rate was observed between months of December and March. RSV remains important viral etiological agent causing influenza-like illness and severe acute respiratory infections especially among infants in Morocco. Further surveillance, is required to understand better the risk factors of RSV infections.

Circulation of Respiratory Syncytial Virus in Morocco during 2014-2016: Findings from a sentinel-based virological surveillance system for influenza

Respiratory syncytial virus [RSV] is a leading cause of mortality and morbidity in young infants, little was known on its circulation types and patterns in Morocco. We conducted a prospective study using sentinel-based influenza surveillance to detect RSV by real time PCR in patients with acute respiratory infections, enrolled during two seasons [2014/15, 2015/16]. During September 2014-April 2016, we obtained 1450 specimens, of which 267 [18.4%] tested positive for RSV. The proportion of positive RSV infection was higher in patients hospitalized with acute respiratory infection compared to those with mild symptoms in out-patient clinics. The proportion of RSV infection was highest in children aged 0-6 months [45%; P < 0.001]. Higher positivity rate was observed between months of December and March. RSV remains important viral etiological agent causing influenza-like illness and severe acute respiratory infections especially among infants in Morocco. Further surveillance, is required to understand better the risk factors of RSV infections

Bien que le virus respiratoire syncytial [VRS] soit l'une des principales causes de mortalité et de morbidité chez les jeunes nourrissons, les modes et les tendances de la circulation de ce virus au Maroc sont très peu connus. Nous avons réalisé une étude prospective en recourant à la surveillance de la grippe basée sur des sites sentinelles dans le but de dépister le VRS grâce à la PCR en temps réel chez des patients souffrant d'infections respiratoires aiguës recrutés au cours de deux saisons [2014-2015 et 2015-2016]. De septembre 2014 à avril 2016, nous avons prélevé 1450 échantillons, parmi lesquels 267 [18,4%] se sont avérés positifs au VRS. La proportion d'infections positives au VRS était plus élevée chez les patients hospitalisés pour une infection respiratoire aiguë que chez les patients en consultation externe souffrant de légers symptômes. Cette proportion était la plus élevée chez les enfants de 0 à 6 mois [45% ; p < 0,001]. Le pic du taux de positivité a eu lieu de décembre à mars. Le VRS demeure un agent étiologique viral important au Maroc, responsable de syndromes de type grippal et d'infections respiratoires aiguës sévères, en particulier chez les nourrissons. Une surveillance renforcée est indispensable pour mieux comprendre les facteurs de risque des infections à VRS

Detection of influenza B viruses with reduced sensitivity to neuraminidase inhibitor in Morocco during 2014/15 season

We monitored phenotypic and genotypic susceptibility of influenza viruses circulating in Morocco during 2014-2015 to oseltamivir and zanamivir. Throat and nasal swab specimens were collected from outpatients [with influenza-like illness] and inpatients [with severe acute respiratory illness] and tested for influenza viruses using real-time reverse transcription polymerase chain reaction. Positive samples were inoculated in MDCK cells and virus phenotypic susceptibility to neuraminidase inhibitors [NAIs] was assessed using fluorescent NA inhibition. Of 440 specimens, 135 were positive for influenza B Yamagata-like virus, 38 were A[H1N1] pdm09 and 25 were A[H3N2]. Sixty influenza B viruses isolated from MDCK cells showed no significant resistance to NAIs. However, two of these strains, B/Morocco/176H/2015 and B/Morocco/CP10/2015, showed reduced susceptibility to oseltamivir. The two influenza B viruses with reduced susceptibility to oseltamivir show that ongoing NAI susceptibility surveillance is essential

Nous avons surveillé le profil de sensibilité phénotypique et génotypique des virus de la grippe à l'oseltamivir et au zanamivir durant la saison 2014-2015 au Maroc. Des échantillons ont été prélevés [par frottis de gorge ou écouvillonnage du nez] chez des patients externes [présentant un syndrome de type grippal] et chez des patients hospitalisés [présentant une infection respiratoire aiguë sévère]. Ils ont été soumis au test de détection des virus de la grippe A et B via la méthode d'analyse RT-PCR simplex en temps réel. Les échantillons positifs ont été inoculés à des cellules rénales canines Madin-Darby [MDCK] et le profil de sensibilité phénotypique des virus isolés aux INA a été évalué au moyen du test d'inhibition de la neuraminidase [NA] par fluorescence. Sur 440 échantillons, 135 [31%] étaient positifs au virus de la grippe B de type Yamagata, 38 [8%] à celui de la grippe A[H1N1]pdm09 et 25 [6%] à celui de la grippe A[H3N2]. Soixante virus de la grippe B isolés sur les culture de cellules MDCK et soumis au test de sensibilité aux INA n'ont démontré aucune résistance significative aux INA. Toutefois, deux de ces souches, la B/Maroc/176H/2015 et la B/Maroc/CP10/2015, ont démontré une sensibilité réduite à l'oseltamivir. Les deux virus de la grippe B ayant une sensibilité réduite à l'oseltamivir montrent l'importance d'une surveillance permanente de la sensibilité à l'inhibiteur de la neuraminidase