Yellow Fever Treatment & Management

There is mandated reporting to the WHO of all suspected or confirmed yellow fever cases within 24 hours of detection. Cases should also immediately be reported to the local health department.

No specific treatment exists for yellow fever; however, supportive care is critical. Severely ill patients should be treated in an intensive care setting. The required management consists of vasoactive medications, fluid resuscitation, ventilator management, and treatment of disseminated intravascular coagulation, hemorrhage, secondary infections, and renal and hepatic dysfunction.

Endotracheal intubation may be required in patients with significant hemorrhage, pulmonary edema, secondary bacterial infections, and shock.

Central venous access may be required for vasopressors and medications when patients enter the toxic stage of the illness.

To manage coagulopathy in yellow fever, the following recommendations have been made:

• In actively bleeding patients, administer fresh frozen plasma to maintain prothrombin time at 25-30 seconds
• In patients with DIC, heparin has been recommended for treatment.

Additional supportive care recommendations for patients with yellow fever include the following:

• A nasogastric or orogastric tube may be required to provide nutritional support
• Patients with renal failure or refractory acidosis may require dialysis
• Salicylates should be avoided because of the increased risk of bleeding secondary to platelet dysfunction

Transmission prevention

Because viremic patients bitten by mosquitoes can transmit the virus to other patients, the patient should be isolated with mosquito netting in areas with potential vector mosquitoes.

Yellow fever virus is not transmitted person to person, but other infections in the differential diagnoses can be transmitted; thus, the patient should be isolated until a definitive diagnosis is made.

Adherence to universal precautions is mandatory to prevent transmission to health care workers. One case of infection of a health care worker (a phlebotomist) has been reported. However, no documented needlesticks or blood splashes explained the transmission in this case.

Treatment of yellow fever principally is symptomatic and preventative. Closely monitor patients for hypovolemia, oliguria, hypoxia, acidosis, and electrolyte imbalance. Hypotension and hypoxia may aggravate hepatic and renal injury.

Intravascular volume may decrease secondary to sequestration in the extravascular space and fluid loss through insensible losses, vomiting, and capillary leak. Invasive arterial blood pressure monitoring may be warranted.

Monitor central venous pressure, peripheral blood pressure, as well as surrogates for organ perfusion and regional blood flow (eg, capillary refill, urinary output, ScvO₂). Monitor acid-base disturbances and metabolic acidosis via arterial blood gas sampling.

Replacement of red blood cells and clotting components will be necessary to treat hemorrhage and shock. Consider vasopressor support for those patients who remain hypotensive despite volume resuscitation and further management of shock.

Patients with respiratory failure, acute respiratory distress syndrome (ARDS), or both may require endotracheal intubation and mechanical ventilation. In those cases, nasogastric suction is essential to prevent gastric distention and aspiration of gastric contents.

Other points to remember include the following:

• Renal failure may necessitate dialysis
• H2-receptor antagonists and proton pump inhibitors may be valuable in preventing gastric bleeding
• Use of cooling blankets and tepid sponging can reduce fever and, thus, oxygen consumption
• Hypothermia frequently occurs late in the disease course and is corrected with gradual rewarming
• Consider parenteral alimentation; hypoglycemia can be prevented by infusion of 10-20% glucose solution

Prevention remains the cornerstone to minimizing the risk of yellow fever. Travelers to endemic areas and local populations should be vaccinated. The currently available vaccine confers near lifelong immunity in 95% of patients.^[11] For travel certification, revaccination is recommended every 10 years.

International Health Regulations allow countries to require proof of vaccination before allowing travelers to enter or leave. Travelers should have a completed International Certificate of Vaccination or Prophylaxis (ICVP). Only the most recent ICVP form CDC 731 complies with the International Health Regulations. For specific information regarding vaccination, see the CDC's Traveler's Health Web site.^[18]

Preventive measures also include staying in air-conditioned or properly screened sleeping quarters and wearing protective clothing, long sleeves, and long pants. Travelers should consider using DEET (N,N -diethyl-meta-toluamide)-containing insect repellent spray.

Eradication challenges

Yellow fever will likely not be eradicated in the near future. Various mosquito species transmit the sylvatic form via nonhuman primates in the jungles and moist savannas;^[3] this ongoing life cycle does not require humans for the spread of disease. Additionally, urbanization and deforestation have reintroduced the virus into areas of previous inactivity. New outbreaks and epidemics continue to reemerge in regions of Africa and South America previously not considered at risk.

At present, the burden of disease internationally is greater than the resources available for proper surveillance and mass vaccination.^[6] Yellow fever also carries the potential threat of use as a bioterrorist agent;^[4] however, other viral hemorrhagic fevers pose a greater risk because of their lack of prophylactic protection.