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Procedures for In Vitro Cultivation of Treponema pallidum, the Syphilis Spirochete
Published on: January 24, 2025
Is there any evidence that syphilis epidemics cycle?
Romulus Breban1, Virginie Supervie, Justin T Okano
1Department of Psychiatry, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA 90024, USA.
The Lancet. Infectious Diseases
|August 23, 2008
Summary
This study re-examined the syphilis epidemic cycling hypothesis using US Centers for Disease Control and Prevention (CDC) data. Findings suggest syphilis epidemics do not cycle, supporting potential CDC syphilis elimination efforts.
Area of Science:
- Epidemiology
- Infectious Disease Dynamics
- Public Health
Background:
- A controversial hypothesis suggests syphilis epidemics exhibit cyclical patterns.
- Previous studies utilized spectral analysis on US Centers for Disease Control and Prevention (CDC) data to support this hypothesis.
Purpose of the Study:
- To re-examine the evidence for cyclical syphilis epidemics.
- To validate or refute the transmission model used to support the cycling hypothesis.
Main Methods:
- Reanalysis of a longitudinal US CDC dataset using spectral analysis.
- Analysis of a longitudinal US CDC mortality dataset.
- Simulation of the syphilis transmission model with varied parameter values.
Main Results:
- Neither CDC dataset provided compelling evidence for cyclical syphilis epidemics.
- The syphilis transmission model, with more reasonable parameters, did not predict cyclical behavior.
- Identified potential reasons for the original proposal of syphilis epidemic cycling.
Conclusions:
- The hypothesis of cyclical syphilis epidemics is not supported by the analyzed data.
- Findings suggest syphilis elimination by the CDC within decades is a feasible public health goal.
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