Received: 15 February 2021
Accepted: 28 April 2021
First Online: 11 May 2021
: Ethical approval for this study was waived by the Animal Research Committee of the National Institute of Animal Health, National Agriculture and Food Research Organization, because it did not include any experimental research on animals and the surveillance data was provided by the Ministry of Agriculture, Forestry and Fisheries (MAFF) based on the contract of the research project. The data that support the findings of this study were used under permission from MAFF for the current study.
: Not applicable.
: The authors declare that they have no competing interests.