Search

Your search keyword '"Goka, Koichi"' showing total 332 results
Start Over Author "Goka, Koichi"
332 results on '"Goka, Koichi"'

10. No Evidence of SARS‐CoV‐2 Infection in Urban Wildlife of Hokkaido, Japan.

Author

Kovba, Anastasiia, Nao, Naganori, Shimozuru, Michito, Sashika, Mariko, Takahata, Chihiro, Sato, Kei, Uriu, Keiya, Yamanaka, Masami, Nakanishi, Masanao, Ito, Genta, Ito, Mebuki, Minamikawa, Miku, Shimizu, Kotaro, Goka, Koichi, Onuma, Manabu, Matsuno, Keita, Tsubota, Toshio, and Al Salihi, Karima

Subjects
URBAN animals, SIKA deer, SARS-CoV-2 Delta variant, SARS-CoV-2 Omicron variant, RACCOON dog, BROWN bear
Abstract

Various domestic and wildlife species have been found susceptible to and infected with SARS‐CoV‐2, the causative agent of COVID‐19, around the globe, raising concerns about virus adaptation and transmission to new animal hosts. The virus circulation in the white‐tailed deer population in North America has further called to action for virus surveillance in the wildlife. Here, we report on the first SARS‐CoV‐2 survey of wild animals in Japan, where frequent wildlife invasions of urban areas have occurred due to the limited predation, field abandonment, the increase of human acclimatization. Genetic testing using nasal swabs and serological screening have been conducted for sika deer, brown bears, raccoons, and raccoon dogs captured in Hokkaido prefecture from the end of the Delta variant wave to the spread of the Omicron variant, between March 2022 and February 2023. No viral RNA was detected in raccoons (0/184), sika deer (0/107), and brown bears (0/14) indicating that the virus was unlikely to spread within the population of these animal species. Among 171 raccoons, 20 raccoon dogs, 100 sika deer, and 13 brown bears, one raccoon, one brown bear, and two deer tested positive in the antibodies screening with multispecies SARS‐CoV‐2 N‐protein ELISA. Still, ELISA‐positive samples tested negative in three other serological tests, emphasizing the importance of confirming serological screening results. Our results suggested that SARS‐CoV‐2 was unlikely to spillback from humans to wildlife in Hokkaido during the study period, with the emergence of new variants, continuous surveillance is of utmost importance. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

17. The importance of the ecology of infectious diseases in the context of Chytridiomycosis and COVID-19

Author

Goka Koichi

Subjects
Environmental Engineering
Abstract

Pathogenic microorganisms and viruses are components of ecosystems. They have constructed endemic interrelationships with specific host species throughout the history of coevolution The spillover of pathogens from natural habitats into other areas causes encounters between the pathogens and new hosts that have never evolved immunity or resistance. The result is a rapid spread of “Emerging Infectious Disease” (EID). During the acceleration of globalization, humans and societies have come to be the targets of infectious diseases caused by pathogens that have emerged from natural habitats. In the past few years, the newest EID, SARS-CoV-2, has spread throughout the world and has caused serious harm to human health and welfare. With the growing social concern about the risks of the EID pandemic, there has been discussion that the destruction of biodiversity and environmental changes are closely related to the EID pandemic. There is a need to rethink the importance of conserving biodiversity if humans are to control the risk of pathogenic viruses and live in harmony with them.

Published
2023

49. Efficiency of ant-control agents in colony-level oral toxicity tests using Tetramorium tsushimae(Hymenoptera: Formicidae) for post-establishment control of the red imported fire ant, Solenopsis invicta(Hymenoptera: Formicidae)

Author

Sakamoto, Hironori and Goka, Koichi

Abstract

The red imported fire ant Solenopsis invictaBuren (Hymenoptera: Formicidae) causes serious damage worldwide as an invasive alien species. The species has expanded its range to the Pacific Rim since 2000s and Japan has faced its multiple introductions since 2017. While colony-level control methods are urgently needed, testing living colonies of the unestablished species is challenging especially due to various restrictions under the COVID-19 pandemic. Here, we proposed alternative long-term toxicity assays using artificial colonies of Tetramorium tsushimaeEmery (Hymenoptera: Formicidae), a Japanese native species belonging to the same subfamily (Myrmicinae) as S. invicta. We conducted an acute toxicity test to determine if T. tsushimaeis a suitable substitute for S. invictausing fipronil and found the LD50value in T. tsushimaewas close to that in S. invicta. Then, we conducted the long-term toxicity test with fipronil and two insect growth regulators (pyriproxyfen and etoxazole) using artificial colonies of T. tsushimae. All workers and larvae in the fipronil-treated colonies died within 3 days of treatment initiation. Emergence of new workers was observed after 18 days in the etoxazole-treated and control colonies, but not in the pyriproxyfen-treated colonies. We concluded that fipronil was the most promising insecticide for post-establishment control, and pyriproxyfen was effective as a toxic-bait agent for colony-level control.

Published
2023
Full Text
View/download PDF

50. The invasion of alien ants across continents with special reference to Argentine ants and Red Imported Fire Ants

Author

Inoue, Maki N. and Goka, Koichi

Subjects
Ant control -- Methods, Invasive species -- Distribution, Invasive species -- Environmental aspects, Invasive species -- Genetic aspects, Invasive species -- Research, Invasive species -- Control, Biological diversity conservation -- Methods, Fire ants -- Distribution, Fire ants -- Control, Fire ants -- Genetic aspects, Company distribution practices, Environmental issues, Science and technology
Published
2009

Catalog

Books, media, physical & digital resources
See catalog results