Yellow fever is one of those scary diseases that most of us have never seen before. Many of us have read about the crippling outbreak and widespread yellow fever transmission that occurred during the construction of the Panama Canal and how it impacted public health. Some of us may not realize that it once occurred in many parts of the United States as far north as Philadelphia.
Currently there is an outbreak in the Amazonian jungles of Brazil. There is concern that cases may start appearing in the United States. Tomorrow someone in your clinic may be presenting with early signs of yellow fever. Will you be ready? The analytics presented throughout the discussion can help to identify problems early.
Clinical Presentation
The early stages of yellow fever are similar to many other diseases that travelers can contract. The patient may present with fever and systemic symptoms. Later when liver damage is evident and the patient becomes jaundiced then the diagnosis may be considered.
- Clinical Features of Yellow Fever
- Conditions Associated with Fever of Unknown Origin (FUO)
Severe cases develop acute hepatic and then multi-organ failure. At this point the prognosis is poor.
- Criteria for Acute Liver Failure
- BiLE (Bilirubin, Lactate, Etiology) Score for Acute Liver Failure (ALF)
- Criteria for Predicting Outcome of Fulminant Hepatic Failure
Differential Diagnosis
There are many other tropical diseases that need to be considered in the differential diagnosis. Malaria, dengue fever, Zika virus and chikungunya fever are just a few. Since these are prevalent in the tropics, they may be considered initially. Only later may the true diagnosis be made.
- Clinical Features of Chikungunya Fever
- Zika Virus (ZIKV) Infection (Zika Fever)
- Model for Identifying an Adult at Risk for Dengue Hemorrhagic Fever
Prevention
Prevention is the best way of dealing with yellow fever. Fortunately, there is a yellow fever vaccine, although it is not without its problems. Countries endemic for yellow fever require proof of vaccination before permitting entry. Unfortunately, some travelers try to seek an exemption in order to avoid the vaccine. This can be a very bad decision.
Another strategy is to take measures to reduce the likelihood of diseases in the differential diagnosis, such as malaria, typhoid fever and viral hepatitis. Avoiding mosquito bites can minimize multiple threats.
- Classifying the Risk of Malaria Transmission for a Traveler
- Prevention of Viral Hepatitis A in a Traveler
Take-Home Message
With modern airline transportation tropical diseases may be just a few hours away. Many of us are unfamiliar with these infections, and often there is a delay in diagnosis as we try to peg them to something that we have seen before.
Medical algorithms can help us to broaden our expertise and recognize problems early. This can be critical for the patient and when there is a public health threat.
