Outdoor infectious diseases surveillance by using hunting dogs in Japan

Hunting dogs are always wandering around bushes and forests to catch wild mammals and birds. There is high risk to get bite with ticks as well as via wildlife. To access risk of tick-born infectious diseases including... [ view full abstract ]

Hunting dogs are always wandering around bushes and forests to catch wild mammals and birds. There is high risk to get bite with ticks as well as via wildlife. To access risk of tick-born infectious diseases including zoonosis, we are doing a serological survey by using serum of hunting dogs which are usually exposed to risks of infection from ticks or wild animals. This assessment may be useful to estimate risks for people who are working with them. A total of 5-6 cc of blood sample was collected from about 600 hunting dogs kept in 22 prefectures throughout Japan, including Kyushu, Sikoku, Tyubu, Tohoku, and Hokkaido districts, as well as various islands and peninsulas. The collected blood was centrifuged, and the serum was examined for various tick-born domestic or zoonotic diseases such as Severe Fever with Thrombocytopenia Syndrome (SFTS), Lyme disease (Borreliosis), canine protozoa Babesia gibsoni and Hepatozoon canis. Various positive results were observed in diseases such as SFTS and Borreliosis which varied largely depending on the districts. Of the positive cases, a large proportion were from those collected in Kyushu districts, especially hepatozoonosis and canine filaliosis. Based on these surveys, in some infections such as Borreliosis, there is a correlation to the incidence and distribution of human patients. It may be useful to monitor blood sample of hunting dogs in various districts to assess risks of outdoor tick-born or wildlife-related infectious diseases in humans. In order to analyze the spectrum of field zoonotic infections for a detailed hazard map of each region, it is necessary to increase the number of sample cases from hunting dogs.