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STUDIES ON THE FILTRABILITY OF BACTERIUM GRANULOSIS
P K Olitsky1, R E Knutti, J R Tyler
1Laboratories of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Trachoma
Area of Science:
- Ophthalmology
- Microbiology
- Virology
Background:
- Trachoma's etiological agent has been debated, with some evidence suggesting a filtrable virus.
- Bacterium granulosis has been implicated, but its role and filtrability remain unclear.
Purpose of the Study:
- To investigate the filtrability of the trachoma agent.
- To determine if Bacterium granulosis is the cause of trachoma or if it's associated with a filtrable virus.
Main Methods:
- Filtration experiments using trachomatous material and Bacterium granulosis suspensions.
- Inoculation of humans and monkeys with filtrates.
- Microscopic examination of tissues for inclusion bodies and bacterial presence.
Main Results:
- The etiological agent of trachoma is generally not filtrable.
- Bacterium granulosis was not consistently recovered from filtrates of trachomatous tissues.
- Inclusion bodies, previously thought to indicate a viral cause, may be bacterial in origin and are not specific to trachoma.
Conclusions:
- Evidence strongly suggests the trachoma agent is not a filtrable virus.
- Bacterium granulosis is unlikely to be the etiological agent or adsorbed to a viral cause.
- The concept of trachoma being caused by an ultramicroscopic virus is not supported by current evidence.
