Estimated number of patients with influenza A(H1)pdm09, or other viral types, from 2010 to 2014 in Japan

Yoshitaka Murakami, Shuji Hashimoto, Miyuki Kawado, Akiko Ohta, Kiyosu Taniguchi, Tomimasa Sunagawa, Tamano Matsui, Masaki Nagai

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)


Infectious disease surveillance systems provide information crucial for protecting populations from influenza epidemics. However, few have reported the nationwide number of patients with influenza-like illness (ILI), detailing virological type. Using data from the infectious disease surveillance system in Japan, we estimated the weekly number of ILI cases by virological type, including pandemic influenza (A(H1)pdm09) and seasonal-type influenza (A(H3) and B) over a four-year period (week 36 of 2010 to week 18 of 2014). We used the reported number of influenza cases from nationwide sentinel surveillance and the proportions of virological types from infectious agents surveillance and estimated the number of cases and their 95% confidence intervals. For the 2010/11 season, influenza type A(H1) pdm09 was dominant: 6.48 million (6.33-6.63), followed by types A(H3): 4.05 million (3.90-4.21) and B: 2.84 million (2.71-2.97). In the 2011/12 season, seasonal influenza type A(H3) was dominant: 10.89 million (10.64-11.14), followed by type B: 5.54 million (5.32-5.75). In conclusion, close monitoring of the estimated number of ILI cases by virological type not only highlights the huge impact of previous influenza epidemics in Japan, it may also aid the prediction of future outbreaks, allowing for implementation of control and prevention measures.

Original languageEnglish
Article numbere0146520
JournalPloS one
Issue number1
Publication statusPublished - 01-01-2016

All Science Journal Classification (ASJC) codes

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)
  • General


Dive into the research topics of 'Estimated number of patients with influenza A(H1)pdm09, or other viral types, from 2010 to 2014 in Japan'. Together they form a unique fingerprint.

Cite this