Zoonotic Infection With Oz Virus, a Novel Thogotovirus

Ngo T.B. Tran; Hiroshi Shimoda; Keita Ishijima; Kenzo Yonemitsu; Shohei Minami; Supriyono; Yudai Kuroda; Kango Tatemoto; Milagros V. Mendoza; Ryusei Kuwata; Ai Takano; Masahiko Muto; Kyoko Sawabe; Haruhiko Isawa; Daisuke Hayasaka; Ken Maeda


Emerging Infectious Diseases. 2022;28(2):436-439. 

In This Article

Abstract and Introduction


Oz virus is a novel thogotovirus isolated from ticks that causes lethal infection in mice. We conducted serosurveillance of Oz virus infection among humans and wild mammals in Japan using virus-neutralization tests and ELISAs. Results showed that Oz virus may be naturally infecting humans and other mammalian hosts.


The genus Thogotovirus, family Orthomyxoviridae, comprises viruses that are most frequently transmitted by a variety of hard and soft tick species.[1] Although most thogotoviruses are associated with tick species, there are several exceptions, such as Sinu virus, which was isolated from mosquitoes;[2] Dielmo orthomyxovirus, isolated from Culicoides midges;[3] and Araguari virus, isolated only from vertebrates.[4] Thogoto, Dhori, and Bourbon viruses have been associated with human disease. Thogoto and Dhori viruses have been reported to cause encephalitis, febrile illness, and death in humans,[5,6] and Bourbon virus to cause febrile illness and death in humans.[7] In addition, Thogoto virus has been reported to cause abortions in sheep,[8] and many wild animals are positive for Bourbon virus antibodies.[9]

Oz virus, a new member of the genus Thogotovirus, was first isolated from a pool of 3 Amblyomma testudinarium tick nymphs collected in Ehime prefecture, Japan.[10] Phylogenetic analyses revealed that Oz virus is more closely related to Dhori, Batken, and Bourbon viruses than to other thogotoviruses.[10] In addition, Oz virus has been shown to cause lethal infection in experimentally challenged suckling mice. To determine the potential of Oz virus as a zoonotic pathogen, we performed serosurveillance of Oz virus infection among mammals, including humans, in Japan.