[1] Fac Vet Sci, Dept Vet Microbiol, Bangkok, Thailand
[2] Chulalongkorn Univ, Fac Pharmaceut Sci, Dept Pharmacognosy & Pharmaceut Bot, Bangkok, Thailand
[3] Natl Ctr Vet Diag, Virol Sect, Dept Anim Hlth, Hanoi, Vietnam
[4] Chulalongkorn Univ, Fac Pharmaceut Sci, Dept Pharmaceut & Ind Pharm, Bangkok, Thailand