TY - JOUR
T1 - In vitro neuraminidase inhibitory concentration (IC50) of four neuraminidase inhibitors in the Japanese 2017–18 season
T2 - Comparison with the 2010–11 to 2016–17 seasons
AU - Ikematsu, Hideyuki
AU - Kawai, Naoki
AU - Chong, Yong
AU - Bando, Takuma
AU - Iwaki, Norio
AU - Kashiwagi, Seizaburo
PY - 2019/8
Y1 - 2019/8
N2 - To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) of the viruses epidemic in the 2017-18 Japanese influenza season, we measured the 50% inhibitory concentration (IC50) for influenza virus isolates from patients and compared them with the results from the 2010–11 to 2016-17 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 IC50 was determined by a neuraminidase inhibition assay using a fluorescent substrate. A total of 237 virus isolates, 50 A(H1N1)pdm09, 92 A(H3N2), and 95 B were measured. No A(H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2017-18 season. No isolates with highly reduced sensitivity to the four NAIs have been found for A(H3N2) or B from the 2010–11 to 2017-18 seasons. The geometric mean IC50s of the four NAIs were quite consistent during the eight studied seasons. These results indicate that the sensitivity to the four commonly used NAIs has been maintained.
AB - To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) of the viruses epidemic in the 2017-18 Japanese influenza season, we measured the 50% inhibitory concentration (IC50) for influenza virus isolates from patients and compared them with the results from the 2010–11 to 2016-17 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 IC50 was determined by a neuraminidase inhibition assay using a fluorescent substrate. A total of 237 virus isolates, 50 A(H1N1)pdm09, 92 A(H3N2), and 95 B were measured. No A(H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2017-18 season. No isolates with highly reduced sensitivity to the four NAIs have been found for A(H3N2) or B from the 2010–11 to 2017-18 seasons. The geometric mean IC50s of the four NAIs were quite consistent during the eight studied seasons. These results indicate that the sensitivity to the four commonly used NAIs has been maintained.
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U2 - 10.1016/j.jiac.2019.04.007
DO - 10.1016/j.jiac.2019.04.007
M3 - Article
C2 - 31101530
AN - SCOPUS:85065513322
VL - 25
SP - 649
EP - 652
JO - Journal of Infection and Chemotherapy
JF - Journal of Infection and Chemotherapy
SN - 1341-321X
IS - 8
ER -