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Updated: Aug 13, 2026
08:33
A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti
Published on: May 16, 2011
Update on the Pathophysiology of Yellow Fever Intoxication
Amaro Nunes Duarte-Neto1, Yeh-Li Ho2, Esper G Kallas2
1Department of Pathology, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.
The American Journal of Tropical Medicine and Hygiene
|August 11, 2026
Summary
Severe yellow fever (YF) involves multiorgan damage, not just the liver. Gut bacteria translocation and sepsis contribute to high mortality, necessitating new treatment strategies.
Area of Science:
- Virology
- Pathophysiology
- Public Health
Background:
- Yellow fever virus (YFV) poses a significant global health risk, exacerbated by climate change and vaccine scarcity.
- The pathophysiology of severe yellow fever (YF), particularly the lethal intoxication phase, is not well understood.
- Recent epidemics and animal models suggest YFV causes a multiorgan syndrome, not solely liver damage.
Purpose of the Study:
- To re-evaluate the pathophysiology of severe YF based on recent clinical and experimental data.
- To propose a gut-centered framework for understanding YF intoxication.
- To identify key factors contributing to high YF mortality.
Main Methods:
- Analysis of clinical data from the 2016-2019 São Paulo YF epidemic.
- Review of recent advances in YFV animal models.
- Integration of findings to develop a new conceptual framework.
Main Results:
- YFV infection leads to endothelial damage and hypotension, causing intestinal ischemia and barrier dysfunction.
- Gut bacteria translocation into the portal system occurs due to liver damage.
- Secondary polymicrobial sepsis develops, contributing significantly to YF mortality.
Conclusions:
- Severe YF is a complex multiorgan syndrome with a critical gut-intestinal component.
- Secondary sepsis and vascular leakage are key features of YF intoxication.
- Optimized fluid management, early dialysis, and antimicrobial therapy are crucial for improving YF outcomes.
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