Yellow fever vaccine-associated viscerotropic disease (YEL-AVD) is a rare and serious adverse event associated with administration of the yellow fever vaccine. YEL-AVD is an illness similar to wild-type yellow fever, in which the vaccine virus proliferates in multiple organs, causing multiple organ dysfunction syndrome or multiorgan failure and death in at least 60% of cases. Since this complication was first recognized in 2001, more than 65 cases have been reported throughout the world. Viscerotropic disease has been reported in primary vaccinees only, with average onset 4 days (range: 0–8 days) after vaccination. Based on a recent analysis of VAERS data, the rate of YEL-AVD in travelers from the United States is 0.4/100,000 doses distributed.
Initial symptoms of YEL-AVD are nonspecific and can include the following: fever, malaise, headache, myalgia, vomiting, and diarrhea. More severe cases can progress to hepatic, renal, or respiratory insufficiency or failure; hypotension; thrombocytopenia; and coagulopathy.
There is no specific therapy for YEL-AVD. Treatment is supportive, once other diseases have been excluded. The diagnosis can be made by the presence of yellow fever vaccine virus detected by RT-PCR from serum or tissues.