Pursuant to a legislative requirement, GAO reviewed the operation of the vaccine injury trust fund and its adequacy for paying claims and administrative costs, focusing on: (1) which vaccines have accounted for the majority of trust fund expenditures, and whether the vaccines are still being widely administered; (2) how the trust fund has been affected by the addition of new vaccines; (3) whether amounts appropriated for agency administrative costs were sufficient to meet the agency's needs; and (4) the sufficiency of the trust fund balance to meet future program demands.

GAO noted that: (1) two vaccines, accounting for about 88 percent of the trust fund payments for injury claims through 1999, are being phased out of use in the United States; (2) one type of vaccine against pertussis (whooping cough) accounted for about 68 percent of trust fund payments, and one type of vaccine against polio accounted for another 20 percent; (3) trust fund payments for injuries and deaths associated with these two vaccines are expected to decline as the vaccines are replaced with others that to date have resulted in fewer reports of adverse reactions; (4) vaccines against four diseases have been added to the Vaccine Injury Compensation Program (VICP) since 1997, but through December 1999, only 6 of the 285 claims filed related to these vaccines had been adjudicated, and only one $600 payment for attorney fees had been made from the trust fund; (5) historically, claims experience for other vaccines has shown that payments are generally higher for claims with injuries listed on the vaccine injury table, but only five of the claims against new vaccines so far allege an injury listed on the table; (6) for claims with nontable injuries, a lower percentage of petitioners obtain compensation, in part because available medical evidence often is insufficient to prove that the vaccine was responsible, and the amounts awarded often have been less; (7) current annual appropriation levels to reimburse agencies from the trust fund for administrative expenses appear sufficient to meet agency needs; (8) the Department of Health and Human Services administers VICP, with involvement by the Department of Justice and the U.S. Court of Federal Claims to help adjudicate injury claims; (9) in earlier years of the program, administrative expenses incurred by these agencies sometimes exceeded the amounts appropriated from the trust fund to reimburse them; (10) since fiscal year 1996, however, when the trust fund appropriation was increased from about $7.8 million to $9.4 million, appropriated amounts have exceeded actual expenditures by 3 to 11 percent each year; (11) the $1.46 billion trust fund balance appears to provide a more than adequate reserve, given experience to date for claims payments and related administrative costs; and (12) if Congress is concerned about the size of the balance and wants to reduce it or its rate of growth, various options are available to do so.