Oz Virus Infection in 6 Animal Species, Including Macaques, Bears, and Companion Animals, Japan

Area of Science:

• Veterinary Medicine
• Virology
• Epidemiology

Background:

• Oz virus (OZV) is a tick-borne virus identified in Japan, known to cause severe human myocarditis.
• The natural hosts and geographic distribution of OZV have not been previously established.

Purpose of the Study:

• To investigate the prevalence of OZV infection in various wild and domestic animal populations across Japan.
• To determine the geographic distribution of OZV and identify potential reservoirs.

Main Methods:

• Serum samples from wild mammals (boars, deer, macaques, bears), dogs, and cats were collected throughout Japan.
• Virus-neutralizing antibody assays were performed to detect OZV seropositivity.
• Oribonucleic acid (RNA) detection was attempted in animal serum samples.

Main Results:

• High seroprevalence rates for OZV antibodies were observed in Sika deer (56.1%) and Asian black bears (51.0%), as well as significant rates in wild boars (27.5%) and Japanese macaques (19.6%).
• Companion animals also showed seropositivity: 2.8% of dogs and 1.0% of cats.
• OZV RNA was not detected in any tested serum samples, indicating the study focused on past exposure.
• Seropositive animals were predominantly found in central and western Japan.

Conclusions:

• OZV circulates widely among diverse animal species in Japan, including wildlife, domestic animals, and nonhuman primates.
• The distribution of OZV appears concentrated in central and western regions of Japan.
• The findings underscore the need for enhanced surveillance and preventive measures against this tick-borne zoonotic pathogen.