Althen is a bedrock case in the Vaccine program that sets forth the standard of proof necessary for a grant of entitlement under the Vaccine Act.  In Althen, the petitioner ultimately suffered a serial loss of vision in both eyes along with other central nervous system injuries subsequent to the administration of a tetanus toxoid {“TT”} vaccine at age 49.

At hearing, Attorney Chin-Caplan set forth a theory on how the vaccine could lead to the initial loss of vision and the progressive neurological symptoms experienced by petitioner.  The Special Master denied entitlement under a newly articulated framework that he had developed in a prior case.  On a Motion for Review, the US Court of Federal Claims reversed, finding that the special master had exceeded the authority granted to him under the Vaccine Act when he applied his new analytical framework to deny entitlement rather than apply existing law and further held that the denial was not in accordance with established case law.  The Federal Circuit affirmed the reversal and indicated that it was not the special master’s role “to craft a new legal standard to be used in causation-in-fact cases.  In addition, the Althen court specifically addressed elements of the discredited framework applied by the special master and indicated that “requiring medical literature” as the Special Master erroneously did at trial, “prevents the use of circumstantial evidence” and “negates the system established by Congress, in which close calls regarding causation are resolved in favor of injured claimants.”  “The Vaccine Act does not require [petitioners] to provide medical documentation of plausibility, [and thus] cannot require [a] demonstrat[ion] that the specific injury is recognized by said medical documentation of plausibility.”  In its analysis of the Act and existing case law, the Althen court set forth the elements of proof needed to establish a grant of entitlement under the Vaccine Act (“Althen prongs”).  The Althen prongs are now the accepted standard of proof within the Vaccine Program.