Molecular analysis of Neorickettsia risticii in adult aquatic insects in Pennsylvania, in horses infected by ingestion of insects, and isolated in cell culture.
- Journal Article
- Research Support
- Non-U.S. Gov't
- Research Support
- U.S. Gov't
- Non-P.H.S.
Summary
This research reveals that horses, after ingesting adult aquatic insects, show clinical signs of Potomac horse fever. The bacteria causing the disease, Neorickettsia risticii, is transmitted orally from caddis flies to horses, as proven by identical gene sequences in the blood of the horses, the isolates, and the caddis flies eaten by the horses.
Study on Molecular Analysis of Neorickettsia risticii
The main study of this research paper is based on the molecular analysis of Neorickettsia risticii, a bacterium that causes Potomac horse fever in horses. This analysis was conducted on three different sources:
- Horses that developed symptoms of Potomac horse fever after ingesting aquatic insects.
- Adult aquatic insects present around the horses.
- Neorickettsia risticii isolated in a cell culture.
Finding the Link Between Potomac Horse Fever and Aquatic Insects
The researchers discovered that Potomac horse fever in horses, observed as clinical symptoms, occurred after the horses ingested adult aquatic insects. Particularly, they identified the caddis fly as one of the carriers of the bacteria, Neorickettsia risticii, that causes this disease.
Discovering the Oral Transmission of Neorickettsia risticii
The research established that the bacterium Neorickettsia risticii, responsible for causing Potomac horse fever, is orally transmitted from caddis flies to horses. This was confirmed by comparing gene sequences of the 16S rRNA and the 51-kDa antigen from:
- The blood of horses showing symptoms of Potomac horse fever.
- The isolated strains of Neorickettsia risticii obtained via cell culture.
- The caddis flies that were ingested by the horses.
The researchers found that these gene sequences were identical, providing strong evidence of the oral transmission route.
Cite This Article
Publication
Researcher Affiliations
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210-1092, USA.
MeSH Terms
- Animals
- Antigens, Helminth / genetics
- Blood / microbiology
- Culture Media
- Feeding Behavior
- Horse Diseases / microbiology
- Horse Diseases / transmission
- Horses / physiology
- Insecta / microbiology
- Mice
- Molecular Sequence Data
- Pennsylvania
- RNA, Ribosomal, 16S / genetics
- Rickettsiaceae / classification
- Rickettsiaceae / genetics
- Rickettsiaceae Infections / microbiology
- Rickettsiaceae Infections / transmission
- Rickettsiaceae Infections / veterinary
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