Related Experiment Video
Updated: Jun 19, 2026
08:23
Feeding of Ticks on Animals for Transmission and Xenodiagnosis in Lyme Disease Research
Published on: August 31, 2013
THE ETIOLOGY OF COLORADO TICK FEVER.
L Florio1, M O Stewart, E R Mugrage
1Department of Public Health and Laboratory Diagnosis, University of Colorado School of Medicine, Denver.
The Journal of Experimental Medicine
|October 30, 2009
Summary
The infectious agent causing Colorado tick fever can pass through fine filters, indicating it is a virus. This finding aids in understanding and classifying the virus responsible for this tick-borne illness.
Area of Science:
- Virology
- Infectious Diseases
- Microbiology
Background:
- Colorado tick fever is a significant tick-borne illness.
- Understanding the nature of the infectious agent is crucial for disease control.
Purpose of the Study:
- To determine the physical properties of the Colorado tick fever infectious agent.
- To classify the infectious agent based on its ability to pass through filters.
Main Methods:
- Filtration of infectious serum through membranes of varying pore sizes (181 µm and 24 µm).
- Inoculation of hamsters and human volunteers with filtered serum.
- Serial transfer of infectious material in hamsters.
- Monitoring for the development of Colorado tick fever symptoms.
Main Results:
- The infectious agent passed through 181 µm membranes, causing infection in hamsters and a volunteer.
- The agent also passed through 24 µm membranes, infecting hamsters and causing fever upon serial transfer.
- Human volunteers were not infected by 24 µm filtrates, but hamsters were.
- Infectious hamster serum transmitted the disease to a previously uninfected volunteer.
- Passage through normal hamster serum did not transmit the disease, confirming specificity.
Conclusions:
- The infectious agent of Colorado tick fever passes through 24 µm membranes.
- Based on its filterable nature, the agent is classified as a virus.
Related Concept Videos
01:26Rocky Mountain Spotted Fever
Rocky Mountain Spotted Fever (RMSF) is a severe tick-borne illness caused by Rickettsia rickettsii, a Gram-negative, coccobacillary bacterium. This pathogen is an obligate intracellular parasite, requiring a host cell for replication. Transmission occurs through the bite of an infected tick. In the United States, the most important vectors are Dermacentor variabilis (American dog tick) and Dermacentor andersoni (Rocky Mountain wood tick), though other tick species may also serve as vectors.
01:22American Trypanosomiasis
Chagas disease, or American trypanosomiasis, is a vector-borne parasitic infection caused by Trypanosoma cruzi, a flagellated protozoan (kinetoplastid) of the family Trypanosomatidae. The disease is endemic in Latin America, although cases are increasingly reported worldwide due to human migration. Transmission most commonly occurs when feces of infected triatomine bugs contaminate bite wounds or mucosal surfaces; additional routes include congenital, transfusional, transplant-related, and oral...
01:28Toxoplasmosis
Toxoplasmosis, a zoonotic disease caused by the protozoan Toxoplasma gondii, poses significant public health challenges globally due to its high seroprevalence and varied clinical manifestations. As an obligate intracellular parasite, T. gondii can infect all warm-blooded vertebrates, but felids are its only definitive hosts, shedding unsporulated oocysts into the environment. Humans typically acquire the infection through ingestion of tissue cysts in undercooked meat or oocysts from...
01:30Bacterial Phylum Spirochaetes
Spirochetes, unique bacteria in the phylum Spirochaetes, are gram-negative, motile, tightly coiled, slender, and flexible. They inhabit aquatic sediments and animals, with some causing diseases like syphilis. Spirochetes are classified into eight genera based on habitat, pathogenicity, phylogeny, and characteristics.Their distinctive motility arises from endoflagella, located within the cell’s periplasm. These endoflagella anchor at the cell poles and extend along the cell length, encased by a...
01:25Arboviral Encephalitis
Arboviral encephalitis refers to brain inflammation caused by arthropod-borne viruses, particularly those transmitted through mosquito vectors. Among these, West Nile virus (WNV), a member of the Flaviviridae family, is a significant public health concern. WNV is an enveloped, positive-sense, single-stranded RNA virus. Human infection typically begins when an infected mosquito introduces the virus into the dermis during feeding. The primary transmission cycle involves birds as amplifying hosts...
01:25Inhalation Anthrax
Anthrax is a zoonotic disease caused by Bacillus anthracis, a Gram-positive, spore-forming bacterium. It primarily affects herbivorous animals but can be transmitted to humans through skin contact, ingestion, or inhalation of spores.Cutaneous anthrax, the most common form, typically results from direct contact with bacterial spores through skin abrasions and is generally less severe. Gastrointestinal anthrax results from eating undercooked or contaminated meat. It affects the mouth, throat, or...