tetano
Editor, Senior Moderator
J Infect Chemother. 2018 May 11. pii: S1341-321X(18)30115-6. doi: 10.1016/j.jiac.2018.04.009. [Epub ahead of print]
[h=1]In vitro neuraminidase inhibitory concentration (IC[SUB]50[/SUB]) of four neuraminidase inhibitors in the Japanese 2016-17 season: Comparison with the 2010-11 to 2015-16 seasons.[/h] Ikematsu H[SUP]1[/SUP], Kawai N[SUP]2[/SUP], Iwaki N[SUP]2[/SUP], Kashiwagi S[SUP]2[/SUP], Ishikawa Y[SUP]3[/SUP], Yamaguchi H[SUP]3[/SUP], Shiosakai K[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) in the viruses epidemic in the 2016-17 Japanese influenza season, we measured the 50% inhibitory concentration (IC[SUB]50[/SUB]) of these NAIs for influenza virus isolates from patients and compared them with the results from the 2010-11 to 2015-16 seasons. Viral isolation was done with specimens obtained prior to treatment, and the type and subtype was determined by RT-PCR using type- and subtype-specific primers. The IC[SUB]50[/SUB] was determined by a neuraminidase inhibition assay using a fluorescent substrate. A total of 276 virus isolates, 6 A (H1N1)pdm09 (2.2%), 249 A (H3N2) (90.2%), and 21 B (7.6%), had the IC[SUB]50[/SUB] measured for the four NAIs. B isolates included 11 (52.4%), 9 (42.9%), and one (4.8%) of the Victoria, Yamagata, and undetermined strains, respectively. No A (H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2016-17 season. No isolate with highly reduced sensitivity to the four NAIs have been found for A (H3N2) or B from the 2010-11 to 2016-17 seasons. No significant trend of increase or decrease was found in the geometric mean IC[SUB]50[/SUB]s of the four NAIs during the seven studied seasons. These results indicate that the sensitivity to the four commonly used NAIs has been maintained and that any change in the effectiveness of these NAIs would be minute. Common usage of NAIs for patient treatment has not been a driving force in the selection of NAI resistant viruses.
[h=4]KEYWORDS:[/h] 50% inhibitory concentration; Influenza virus; Neuraminidase inhibitor; Resistance; Surveillance
PMID: 29759897 DOI: 10.1016/j.jiac.2018.04.009
[h=1]In vitro neuraminidase inhibitory concentration (IC[SUB]50[/SUB]) of four neuraminidase inhibitors in the Japanese 2016-17 season: Comparison with the 2010-11 to 2015-16 seasons.[/h] Ikematsu H[SUP]1[/SUP], Kawai N[SUP]2[/SUP], Iwaki N[SUP]2[/SUP], Kashiwagi S[SUP]2[/SUP], Ishikawa Y[SUP]3[/SUP], Yamaguchi H[SUP]3[/SUP], Shiosakai K[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) in the viruses epidemic in the 2016-17 Japanese influenza season, we measured the 50% inhibitory concentration (IC[SUB]50[/SUB]) of these NAIs for influenza virus isolates from patients and compared them with the results from the 2010-11 to 2015-16 seasons. Viral isolation was done with specimens obtained prior to treatment, and the type and subtype was determined by RT-PCR using type- and subtype-specific primers. The IC[SUB]50[/SUB] was determined by a neuraminidase inhibition assay using a fluorescent substrate. A total of 276 virus isolates, 6 A (H1N1)pdm09 (2.2%), 249 A (H3N2) (90.2%), and 21 B (7.6%), had the IC[SUB]50[/SUB] measured for the four NAIs. B isolates included 11 (52.4%), 9 (42.9%), and one (4.8%) of the Victoria, Yamagata, and undetermined strains, respectively. No A (H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2016-17 season. No isolate with highly reduced sensitivity to the four NAIs have been found for A (H3N2) or B from the 2010-11 to 2016-17 seasons. No significant trend of increase or decrease was found in the geometric mean IC[SUB]50[/SUB]s of the four NAIs during the seven studied seasons. These results indicate that the sensitivity to the four commonly used NAIs has been maintained and that any change in the effectiveness of these NAIs would be minute. Common usage of NAIs for patient treatment has not been a driving force in the selection of NAI resistant viruses.
[h=4]KEYWORDS:[/h] 50% inhibitory concentration; Influenza virus; Neuraminidase inhibitor; Resistance; Surveillance
PMID: 29759897 DOI: 10.1016/j.jiac.2018.04.009