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Updated: Aug 5, 2026
A Human Fallopian Tube Model for Investigation of C. trachomatis Infections
Published on: August 11, 2012
Pesky trachoma suspect finally caught
Aim:
Face seeking flies have long been thought to transmit Chlamydia trachomatis, the causative agent of trachoma, but this has never been proven. The four criteria proposed by Barnett, previously used to incriminate other arthropods suspected of transmitting disease, were examined. One of these criteria remains unmet: the repeated demonstration of the presence of C trachomatis on flies. The authors used polymerase chain reaction (PCR) to look for the presence of C trachomatis DNA on flies in the Gurage Zone of Ethiopia.
Methods:
Using sticky paper, one fly was collected from the face of each of 103 children aged 1-10 years. The piece of fly paper to which the fly was attached was cut out, followed by the collection of an empty piece from an arbitrary area of the fly paper, which served as control. Roche Amplicor PCR kits were used to detect C trachomatis DNA.
Results:
Evidence of C trachomatis by PCR was found on 15 of 103 flies versus 0 of 103 controls (p = 0.0001).
Conclusion:
These results meet the final criterion needed to incriminate flies as a vector of trachoma. However, interventional studies will be needed to show the importance of fly control.
Insights
Flies can transmit Chlamydia trachomatis, the bacteria causing trachoma. This study detected C. trachomatis DNA on flies collected from children's faces in Ethiopia, providing key evidence for flies as disease vectors.
Area of Science:
- Ophthalmology
- Medical Entomology
- Infectious Diseases
Background:
- Trachoma, a leading cause of preventable blindness, is caused by Chlamydia trachomatis.
- Flies, particularly face-seeking flies, are suspected vectors of trachoma but lack definitive proof.
- Previous research has not consistently demonstrated C. trachomatis presence on flies.
Purpose of the Study:
- To investigate the role of flies as vectors for Chlamydia trachomatis.
- To fulfill the final criterion for implicating flies in trachoma transmission.
- To detect C. trachomatis DNA on flies using polymerase chain reaction (PCR).
Main Methods:
- Flies were collected from the faces of 103 children in Ethiopia using sticky paper.
- Control samples of fly paper were collected from arbitrary areas.
- Roche Amplicor PCR kits were utilized to detect C. trachomatis DNA.
Main Results:
- Chlamydia trachomatis DNA was detected on 15 out of 103 flies.
- No C. trachomatis DNA was found on any of the 103 control samples.
- The difference in detection rates between flies and controls was statistically significant (p = 0.0001).
Conclusions:
- The study provides the first definitive evidence incriminating flies as vectors of trachoma.
- Meeting this criterion supports the need for fly control strategies in trachoma prevention.
- Further interventional studies are required to quantify the impact of fly control on trachoma transmission.
