title: Risk groups for yellow fever vaccine-associated viscerotropic disease (YEL-AVD).
abstract: Although previously considered as the safest of the live virus vaccines, reports published since 2001 indicate that live yellow fever virus vaccine can cause a severe, often fatal, multisystemic illness, yellow fever vaccine-associated viscerotropic disease (YEL-AVD), that resembles the disease it was designed to prevent. This review was prompted by the availability of a listing of the cumulative cases of YEL-AVD, insights from a statistical method for analyzing risk factors and re-evaluation of previously published data. The purpose of this review is to identify and analyze risk groups based on gender, age, outcome and predisposing illnesses. Using a passive surveillance system in the US, the incidence was reported as 0.3 to 0.4 cases per 100,000. However, other estimates range from 0 to 12 per 100,000. Identified and potential risk groups for YEL-AVD include elderly males, women between the ages of 19 and 34, people with a variety of autoimmune diseases, individuals who have been thymectomized because of thymoma, and infants and children ≤11 years old. All but the last group are supported by statistical analysis. The confirmed risk groups account for 77% (49/64) of known cases and 76% (32/42) of the deaths. The overall case fatality rate is 66% (42/64) with a rate of 80% (12/15) in young women, in contrast to 50% (13/26) in men ≥56 years old. Recognition of YEL-AVD raises the possibility that similar reactions to live chimeric flavivirus vaccines that contain a yellow fever virus vaccine backbone could occur in susceptible individuals. Delineation of risk groups focuses the search for genetic mutations resulting in immune defects associated with a given risk group. Lastly, identification of risk groups encourages concentration on measures to decrease both the incidence and the severity of YEL-AVD.
authors.affiliation: Department of Microbiology and Immunology, New York Medical College, 15 Dana Road, Valhalla, NY 10595, United States. Electronic address: stephen_seligman@nymc.edu.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Seligman
mesh_terms: D000328:Adult; D016907:Adverse Drug Reaction Reporting Systems; D001327:Autoimmune Diseases / Q000150:complications; D002648:Child; D002675:Child, Preschool; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D013950:Thymus Gland / Q000503:physiopathology; D022341:Yellow Fever Vaccine / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D022341:Yellow Fever Vaccine
keywords: Risk groups; Vaccine; Viscerotropic; Yellow fever