Determination of host range and global distribution of Babesia sp. Mymensingh, a recently discovered virulent Babesia capable of causing clinical babesiosis in cattle

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K23704
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0605:Veterinary medical science, animal science, and related fields
• Research Institution: Obihiro University of Agriculture and Veterinary Medicine
• Principal Investigator: Sivakumar Thillaiampalam 帯広畜産大学, 原虫病研究センター, 特任研究員 (00826711)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: 牛バベシア病 / Babesia sp. Mymensingh / Babesia bovis / Babesia bigemina / 遺伝子診断法 / 牛 / ラクダ / 疫学調査

Outline of Final Research Achievements

A global epidemiological survey using our molecular diagnostic tool (PCR) revealed that the new Babesia species (Babesia sp. Mymensingh) has a wide distribution in Asia, Africa, and South America. In addition, Babesia sp. Mymensingh has been found in cattle, buffalo, sheep, and goats, showing that it has a broad host range. Moreover, Mongolian cattle were infected with Babesia bovis, B. bigemina, and Babesia sp. Mymensingh, according to a PCR-based survey, with overall positive rates of 27.9%, 23.6%, and 5.4%, respectively. Furthermore, an epidemiological survey of bovine Babesia species showed that Bactrian camels in Mongolia are harboring B. bovis, B. bigemina, and Babesia sp. Mymensingh with overall positive rates of 32.1%, 21.6%, and 24.3%, respectively. In summary, as part of this research project, we have 1) established a new genetic diagnostic method for the specific detection of Babesia sp. Mymensingh, 2) defined its host range, and 3) mapped its epidemiology on a global scale.

Free Research Field

獣医原虫病学

Academic Significance and Societal Importance of the Research Achievements

本研究課題の成果により、新バベシア種（Babesia sp. Mymensingh）を特異的に検出できる新たな遺伝子診断法が確立された。特に本PCR技術を用いて、我が国では新バベシア感染牛の摘発に向けた水際対策に資する防疫体制が整備されることが期待できる。また、本原虫種の最新の感染宿主域と国際疫学マップが明らかとなったことで、地球規模での新バベシアの感染による牛バベシア病のリスク評価が行われ、さらなる国際疫学マップの更新とその対応策が構築されていくものと期待する。