Legal Issues

VACCINE LIABILITY BEFORE 1986

To understand the decisions that were rendered in cases filed against vaccine manufacturers and administrators before 1986, it is important to understand the nature of products liability law as it was evolving in that era. Before the early 1980s, manufacturers were not held liable for the harm associated with a product unless it failed to comply with the standards of manufacturing or care implemented by similarly situated manufacturers. Usually, vaccine manufacturers sued by consumers would prevail because they used customary practices and complied with statutes and regulations and because of the doctrine of the learned intermediary , discussed later.

This standard began to change when, in 1965, the American Law Institute introduced the concept of “strict liability” in its Restatement (Second) of Torts . Although the principles embodied in this Restatement were not applied uniformly to lawsuits against vaccine manufacturers and administrators, they served as guiding principles in the field and were viewed by many as significant emerging legal doctrines.

Under the Restatement ’s doctrine of strict liability, a manufacturer who sold a product in a defective condition that made the product unreasonably dangerous was subject to liability for harm caused to the user or consumer even if the manufacturer exercised all possible care in the preparation and sale of the product. A product was deemed defective if it was in a condition not contemplated by the ultimate consumer, which made it unreasonably dangerous to the consumer. Although the doctrine of strict liability lowered the burden required to find manufacturers liable for the harm caused by their products, the authors of the Restatement recognized that some products were, by their nature, “unavoidably unsafe,” and determined that such products should not be deemed unreasonably dangerous under the doctrine of strict liability. Thus, products such as vaccines, which necessarily entail some risks (risks considered reasonable given their benefits to the community), were not deemed defective or unreasonably dangerous so long as they were properly prepared and accompanied by adequate warnings. Consequently, vaccine manufacturers and administrators were generally not held liable for harm caused by their products before 1986, so long as these requirements of proper preparation and adequate warnings were satisfied.

The risk of liability created by the requirements to properly prepare vaccines and provide adequate warnings is important. If, for instance, a lot of vaccine was defective and caused disease in recipients because the disease-causing agent was not sufficiently inactivated or because of contaminants, the manufacturer could be liable, regardless of whether the defect could be shown to be the manufacturer’s fault. This happened with early lots of Salk poliovirus vaccine, and there were numerous and substantial recoveries by persons who acquired polio from the vaccine. As another example, if a physician administered a vaccine when it was contraindicated (e.g., administered Sabin oral poliovirus vaccine [OPV] to a child known to be immunodeficient or administered a second dose of diphtheria and tetanus toxoids and whole-cell pertussis [DTP] vaccine after a child had a severe adverse reaction to the first), the physician could be liable if the adverse consequence risked by violating the contraindication occurred. Furthermore, if a physician administered a vaccine without warning the patient of the risks, the physician could be liable if the risks occurred.

Despite the limits on liability imposed by general doctrines of products liability law in cases concerning adverse reactions from vaccines, certain judicial decisions in the pre-1986 era imposed liability even when the vaccines were properly made and administered. These cases, which were a significant impetus to the enactment of the NCVIA, can be divided into three categories: the Reyes decision, the swine flu litigation against the government, and the 1980s decisions.

Reyes v Wyeth Laboratories , decided in 1974 by the United States Court of Appeals for the Fifth Circuit, held a manufacturer of OPV liable to a child who contracted paralytic poliomyelitis after being administered the vaccine. The decision broadened the potential liability faced by manufacturers in the context of mass vaccination efforts.

This case articulated an exception to the learned intermediary doctrine. Under the general rule, a manufacturer of prescription medicines, including vaccines, is obliged to provide warnings concerning the product to the healthcare provider (the learned intermediary), but has no duty to directly warn the user of the product of its associated risks. This doctrine assumes that the medical professional makes an individualized medical judgment with respect to the risks and benefits of a particular drug or vaccine for a particular patient. The Reyes decision narrowed this general rule, holding that, when a manufacturer can reasonably be said to be aware that the product (i.e., the vaccine) will be administered in such a way that no personalized medical advice will be provided (e.g., in the context of a public health department’s immunization effort in which the patient had no direct contact with a physician), the manufacturer is responsible for providing warnings directly to patients or ensuring that such warnings will be given.

In Reyes , the manufacturer shipped the vaccines to the Texas Department of Public Health, accompanied by the Food and Drug Administration (FDA)-required package inserts containing warnings concerning the possible consequences of the vaccine. The Texas Department of Public Health sent the vaccine to the county health department without ensuring that the warnings would actually be given to vaccine recipients (or their parents). The nurse who administered the vaccine to the child in this case did not warn the parents of the minute risk that a recipient or contact could contract the disease. Although the Reyes Court determined that OPV was not unreasonably dangerous per se, it concluded that the vaccines were unreasonably dangerous as marketed and that the manufacturer breached its duty because it was aware that the vaccine could result in a particular danger, knew or had reason to know that the vaccine would be administered in circumstances in which vaccine recipients might not be counseled by learned intermediaries (i.e., in mass vaccine clinics), and failed to provide warnings or ensure that such warnings were provided to vaccine recipients.

The next development in the area of vaccine liability involved the swine flu vaccine. In the spring of 1976, leading epidemiologists predicted that the United States could be afflicted the following winter with a strain of influenza that could lead to a pandemic similar to the catastrophic outbreak of 1918. The lack of prior immunity raised fears that many people who contracted the disease would die or suffer serious illness. This prediction led the government to launch a campaign to immunize almost all American adults. ^,

The Reyes decision caused manufacturers to refuse initially to provide the swine flu vaccine to the government. Because manufacturers, concerned about other unforeseen risks of liability in a program this large, did not want to accept any liability for the vaccines. As a result, the Swine Flu Act was passed. This law required vaccine recipients who believed they had been injured to sue the federal government, which served as a substitute defendant for vaccine manufacturers. The swine flu program was a considerable success as a matter of effective public health mobilization, insofar as the vaccine was successfully produced, distributed, and administered to more than 45 million people in a few months. However, vaccination was suspended when the feared swine flu epidemic did not appear and suspicions arose that there might be an association between the vaccine and Guillain-Barré syndrome (GBS). Numerous claims concerning GBS were filed under the Swine Flu Act, many of which relied on a Centers for Disease Control and Prevention (CDC)-sponsored study that showed a statistically significant increase in the risk of GBS in the 10 weeks after immunization compared with the risk in unvaccinated people. The government accepted liability for all cases of GBS with onset falling within this period. The government did not agree to accept liability for cases of GBS falling outside this time interval or for other illnesses. The defense of this litigation resulted in more than 100 judicial opinions, which generally shielded manufacturers and administrators from liability by relying on the Swine Flu Act. However, some courts wrote opinions in the Reyes v Wyeth tradition that imposed increased liability for the federal government based on a theory of inadequate warning, for example, Unthank v United States and Petty v United States , in which the federal government was found derivatively liable for a manufacturer’s failure to provide plaintiffs with adequate warnings covering the risks of the swine flu vaccine.

The efforts of plaintiffs to establish common law, strict tort liability on the part of vaccine manufacturers (i.e., holding the manufacturer liable even if adequate warnings are given and the vaccine is produced and handled in full compliance with FDA regulations) seemed to increase after Reyes and the swine flu episode. In the 1980s, plaintiffs achieved some notable successes. For example, in Johnson v American Cyanamid Co. , the father of a vaccinated child who claimed to have contracted polio through contact with his child sued the manufacturer and administrator of the OPV. The jury found the vaccine manufacturer liable and imposed a $10 million damages award. The Kansas Supreme Court reversed the jury’s verdict and award, determined that there was no manufacturing or design defect, and concluded that the manufacturer’s warning was adequate. The court did not resolve whether the vaccine administrator might have been liable for failing to warn the parents of the vaccine’s risk had this claim been pursued.

In Toner v Lederle Laboratories , a jury returned a verdict of over $1.1 million for a recipient of a DTP vaccine who claimed that the vaccine caused transverse myelitis, a condition that had never been shown scientifically to be caused by any available DTP vaccine. The plaintiff’s theory was that the vaccine caused transverse myelitis, that the defendant could have marketed a safer vaccine (a vaccine once marketed by another manufacturer that was withdrawn from the market in the 1970s), and that the manufacturer’s failure to make a safer version of the vaccine was negligent. The verdict was appealed to the United States Court of Appeals for the Ninth Circuit, which referred the issues to the Idaho Supreme Court. The Idaho Supreme Court affirmed the jury’s verdict that the manufacturer’s design of DTP was negligent.

The results reached in these cases are notable and underscore the fear of liability by vaccine manufacturers and healthcare professionals.

NATIONAL CHILDHOOD VACCINE INJURY ACT

The Reyes v Wyeth decision and its progeny were followed by the withdrawal of several pharmaceutical houses from vaccine production and an increase in the price of vaccines.

The litigious atmosphere of the 1980s and the sharp decrease in the number of vaccine manufacturers had an adverse impact on the research and development of new and safer vaccines. Before a vaccine is marketed and a manufacturer has the possibility of reaping any profit, the FDA requires it to prove that the vaccine is safe and effective. Meeting this burden is costly, and the investment cannot be recovered until the vaccine is marketed. The costs and logistics associated with administering a new vaccine enough times in prelicensure clinical trials to detect rare adverse side effects are high. A manufacturer’s inability to accurately estimate its risk of liability and, therefore, the effect of this potential liability on its profit margin, translated into limited commercial incentives to develop new vaccines.

During this period, the nation’s children were at risk. The American Academy of Pediatrics and the American Medical Association were concerned about the continued availability of vaccines and the possibility that physicians were at risk for liability. At the time, it was common for plaintiffs to join the pharmaceutical company and the administering physician in a complaint, claiming that the physician did not adequately disclose the risk associated with the vaccine. At least one state (North Carolina) enacted legislation protecting participants in the delivery of vaccines from liability and authorizing compensation to injured vaccinees. In the end, the NCVIA of 1986 was compromise legislation for which parents and physicians advocated with some backing of industry and trial attorneys.

NATIONAL VACCINE INJURY COMPENSATION PROGRAM

VACCINE INJURY COMPENSATION PROGRAM CASES SINCE 1986

Without question, the biggest controversy (and challenge) in adjudicating cases filed in the VICP has been determining vaccine causation. The legislative history underlying the NCVIA noted the lingering controversy about what is and is not vaccine-caused, with a recognition that the scientific understanding on these issues would evolve. For the first 8 years after the VICP was created, the vast majority of petitions filed alleged a VIT injury (“Table claim”), which confers the presumption that the injury, significant aggravation, or death were vaccine-related. A VIT-based adjudication was straightforward: A petition would usually allege that the injured person experienced the signs and symptoms described in the VIT, as defined by the Qualifications and Aids to Interpretation (QAIs), within a VIT time frame, regardless of whether these allegations were substantiated or contradicted by the medical record. Accordingly, in the earlier years of the VICP, the special masters and the courts concentrated almost exclusively on developing a body of law establishing the quality and quantity of evidence needed to prove an injury included on the VIT.

Case law generally places more weight on the medical records most contemporaneous to the vaccination than on contradictory evidence assembled later, after memories fade or when litigation is contemplated. In circumstances in which the contemporaneous medical records are contradictory or do not exist, the special masters rely on the evidence provided by the family and the expert witnesses, including making credibility determinations of those witnesses, to determine whether a VIT injury occurred. The appellate courts give deference to special masters’ findings of fact and credibility determinations, as long as they were not arbitrary or capricious.

The courts also have addressed questions concerning whether special masters must strictly apply and interpret the definitions in the QAIs, which accompany the VIT. In Hellebrand v Secretary of Department of Health and Human Services and Hodges v Secretary of Department of Health and Human Services , the U.S. Court of Appeals for the Federal Circuit found that because special masters have wide latitude in adjudicating claims, they are not required to apply the QAIs in a mechanical manner; rather, they have reasonable discretion when applying them.

Shalala v Whitecotton is a landmark Table injury case regarding the meaning of “significant aggravation” under the statute. Significant aggravation is important in VICP cases because if the onset of signs or symptoms following vaccination is not the first evidence of the alleged vaccine-related condition, to receive compensation, the petitioner must prove that the vaccine significantly aggravated a condition present before vaccination. The NCVIA defines significant aggravation as “any change for the worse in a preexisting condition which results in markedly greater disability, pain, or illness accompanied by substantial deterioration of health.” According to the legislative history, an example would be a child whose seizure frequency increased from one per month before vaccination to one per day after vaccination. The special master in Whitecotton denied compensation on the basis that the child was born with a brain disorder that was responsible for the encephalopathy that appeared after receipt of the third DTP vaccination. The Court of Federal Claims agreed, but the U.S. Court of Appeals for the Federal Circuit reversed the decision based on a different interpretation of “first symptom or manifestation of onset,” writing that “first” did not necessarily mean that other clinical signs could not appear before vaccination. The U.S. Supreme Court unanimously reversed the Federal Circuit’s decision, finding that the Federal Circuit misread the NCVIA. However, Justice O’Connor, in a concurring opinion, noted that the Federal Circuit opinion did not address the issue of significant aggravation of a preexisting condition, but instead only addressed the issue of “first symptom or manifestation of onset.” The case was remanded to the Federal Circuit, which set forth a test for Table injury significant aggravation claims, specifying that the special master must (a) assess the person’s condition before the administration of the vaccine, (b) assess the person’s current condition, and (c) determine if the person’s current condition constitutes a significant aggravation of the person’s condition before vaccination within the meaning of the statute; and, if the special master determines there has been a significant aggravation, then the special master must (d) determine whether the first symptom or manifestation of the significant aggravation occurred within the period prescribed by the VIT for the injury. Although Whitecotton involved a Table injury, the courts have applied the significant aggravation test in off-Table claims. ^,

A clarification of the fourth step of the Whitecotton test was announced in Gruber v Secretary of Department of Health and Human Services. The Court of Federal Claims clarified that the special master, in determining the first symptom or manifestation of onset of the significant aggravation, must take into account the preexisting condition. The court found that the definition of the term significant aggravation should more properly be understood as “any change for worse in [the allegedly aggravated Table injury] which results in a markedly greater disability, pain, or illness accompanied by substantial deterioration of health.” Furthermore, the court indicated that the four-step test articulated in Whitecotton does not merge the significant aggravation and sequelae inquiries. Rather, to obtain compensation for sequelae, a petitioner must establish that the aggravation of the Table injury caused them, without reliance on any Table presumption.

More recently, Sharpe v Secretary of Department of Health and Human Services, 964 F. 3d 1072 (Fed Cir 2020), which involved a claim of significant aggravation of an on-Table injury (encephalopathy) or alternatively, an off-Table injury (seizure disorder), the U.S. Court of Appeals for the Federal Circuit agreed that the special master properly found that there was no on-Table significant aggravation claim. However, with respect to the off-Table claim, the petitioner was not required to show that a change in her child’s prevaccination condition following vaccination was worse than the expected outcome of that condition.

The parameters of the factor unrelated defense also have been tested. Under the NCVIA, if petitioners show proof of a Table condition occurring within the specified time, they are entitled to a presumption of vaccine causation unless the government can show preponderant evidence of an alternative cause or factor unrelated. The U.S. Court of Appeals for the Federal Circuit generally used a strict interpretation when it applied the NCVIA’s definition of the term: A factor unrelated may not include “any idiopathic, unexplained, unknown, hypothetical, or undocumentable” condition. In Knudsen v Secretary of Department of Health and Human Services , the U.S. Court of Appeals for the Federal Circuit explained that while there is “nothing” in the NCVIA that “requires a per se rule” that the government identify with specificity the viral infection that is alleged to be the factor unrelated, the government must establish preponderant evidence that the infection “actually caused the table injury complained of.”

However, in off-Table cases, the Federal Circuit has acknowledged that evidence of other sources of the claimed injury can be relevant not only to the “factors unrelated” defense (in which the government bears the burden of proof), but also to whether a prima facie showing has been made by a petitioner that the vaccine in question was a substantial factor in causing the injury. See Stone v Secretary of Department of Health and Human Services . Thus, special masters may consider evidence of a factor unrelated in examining the record as a whole to determine whether petitioners have met their burden of proof in establishing a prima facie case.

The original NCVIA allowed the Secretary of HHS to modify or amend injuries listed in the VIT, which was originally included in the statute, and QAIs (see “Modifying the Vaccine Injury Table” later) by regulation. In petitions filed after the first set of VIT changes took effect, the focus of most claims changed from proving a presumptive VIT injury to proving that the injury was caused-in-fact by the vaccine (i.e., off-Table claims). This shift occurred for several reasons. First, HHS removed residual seizure disorder and shock collapse from the VIT. Second, the QAIs for encephalopathy were revised to more accurately reflect the medical view of significant acute and chronic neurologic injuries, instead of the normal, transient side effects common to some childhood vaccines.

Third, although additional presumptive injuries have been added to the “original” vaccines, few of the new vaccines added to the VIT in recent years have had associated presumptive injuries ( Table 85.5 ). Fourth, several of the new vaccines added to the VIT are also routinely administered to the adult population, expanding the spectrum of claimed injuries. Fifth, the licensure of acellular pertussis vaccines for primary use in infants and the transition to an IPV-only schedule all but eliminated DTP vaccine and OPV filings, the former of which comprised a significant percentage of alleged injury and death claims.

Current cases, therefore, present a challenge for the special masters and the courts to strike an appropriate balance between (a) applying the statutory standard of preponderance of the evidence in the adjudication of claims, and (b) the need to fulfill the VICP’s mandate to provide compensation “generously” and “fairly,” even in the absence of full scientific knowledge about potential vaccine adverse events.

To establish entitlement to compensation under the NCVIA in an off-Table case, a petitioner must prove by preponderant evidence that the vaccine at issue in fact caused the alleged injury. Early in the history of the VICP, the Federal Circuit observed that the NCVIA “relaxes proof of causation for injuries satisfying the Table . . . but does not relax proof of causation in fact for non-Table Injuries” ( Grant v Secretary of Department of Health and Human Services ). Within that context, the Court stated that “a proximate temporal association alone does not suffice to show a causal link between the vaccination and the injury.” Rather, causation-in-fact requires “proof of a logical sequence of cause and effect showing that the vaccination was the reason for the injury. A reputable medical or scientific explanation must support this logical sequence of cause and effect.” The Federal Circuit later clarified that causation-in-fact involves “ascertaining whether a sequence of cause and effect is ‘logical’ and legally probable, not medically or scientifically certain.” Still, there were questions regarding the type of evidence to be considered by fact finders (e.g., whether peer-reviewed literature was required to prevail in a cause-in-fact claim), as well as the weight accorded to that evidence, which have been addressed by the Federal Circuit over time. The following cases examine some of those nuances.

In Shyface v Secretary of Department of Health and Human Services , the Federal Circuit held that petitioners need not show that the vaccine at issue is the predominant cause of the injury or condition. Rather, adopting the Restatement (Second) of Torts , the Court found that for the purpose of determining vaccine injury, a petitioner must establish that the vaccine is a “substantial factor” in bringing about the alleged condition or injury, and that the condition or injury would not have occurred “but for” the vaccine.

In Althen v Secretary of Department of Health and Human Services , the Federal Circuit held that the Vaccine Act did not preclude a finding of compensation in the absence of peer reviewed literature supporting a nexus between the alleged injury and the vaccine at issue, reasoning that “the purpose of the NCVIA’s preponderance standard is to allow the finding of causation in a field bereft of complete and direct proof of how vaccines affect the human body.” Summarizing prior caselaw in a three-prong test, the Court stated that petitioner’s evidentiary burden in an off-Table case was to show by preponderant evidence that the vaccine brought about her injury by providing: “(1) a medical theory causally connecting the vaccination and the injury; (2) a logical sequence of cause and effect showing that the vaccination was the reason for the injury; and (3) a showing of proximate temporal relationship between vaccination and injury.” The Federal Circuit has repeatedly affirmed the applicability of the Althen test in off-Table cases.

A petitioner must satisfy all three parts of the Althen test to prevail in a petition for entitlement to compensation under the NCVIA. De Bazan v Secretary of Department of Health and Human Services , 539 F3d 1347 (Fed Cir 2008). However, once a petitioner establishes a prima facie cause-in-fact claim, the Vaccine Act does not require the petitioner to eliminate other potential alternative causes of the injury. See Walther v Secretary of Department of Health and Human Services. In Capizzano v Secretary of Department of Health and Human Services , the Federal Circuit held that in deciding whether petitioner established a “logical sequence of cause and effect,” the special master was required to consider the opinions of treating physicians (where offered) because “medical records and medical opinion testimony are favored in vaccine cases, as treating physicians are likely to be in the best position to determine whether ‘a logical sequence of cause and effect show[s] that the vaccination was the reason for the injury.’”

In proving a medical theory of causation between a vaccine and an alleged injury, the Court has repeatedly emphasized that a petitioner is neither required to rely on epidemiologic studies, nor show that the theory has general acceptance in the medical community. Andreu v Secretary of Department of Health and Human Services. However, where such evidence is offered, it is not to be evaluated through the lens of a laboratorian, but instead from the vantage point of the preponderance standard.

The Federal Circuit has reaffirmed in several precedential decisions that the applicable level of proof in off-Table vaccine cases is the traditional tort standard of preponderant evidence (i.e., more likely than not), and has squarely rejected evidence of a “plausible” or “possible” causal link to vaccination as legally sufficient. Moberly v Secretary of Department of Health and Human Services ; LaLonde v Secretary of Department of Health and Human Services , 746 F3d 1334, 1341 (Fed Cir 2014).

Although a petitioner in the NCVIA is not required to submit proof of causation to the level of scientific certainty, the special master is “entitled to require some indicia of reliability to support the assertion of an expert witness.” Moberly , supra at 1324 (citing Terran v Secretary of Department of Health and Human Services , 195 F3d 1302, 1306 (Fed Cir 1999). Likewise, it is well-settled that special masters, as finders of fact, are expected to make determinations as to the reliability of the evidence presented to them, and, if appropriate, the credibility of persons presenting that evidence. See Moberly ; Broekelschen v Secretary of Health and Human Services, 618 F3d 1339, 1345 (Fed Cir 2010); Porter v Secretary of Department of Health and Human Services . . However, a special master may not “cloak the application of an erroneous legal standard in the guise of a credibility determination, and thereby shield it from appellate review.” Andreu, supra at 1379. As the Court has clearly stated, ultimately, “the function of a special master is not to ‘diagnose’ vaccine-related injuries, but instead to determine ‘based on the record evidence as a whole and the totality of the case, whether it has been shown by a preponderance of the evidence that a vaccine caused the [person’s] injury.” Id. at 1382 (internal citations omitted).

Boatmon v Secretary of Department of Health and Human Services is one of the more significant VICP cases interpreting Althen in recent years. In Boatmon , the Federal Circuit held petitioners’ medical theory of causation, which was only “medically plausible,” failed to demonstrate a causal connection required for compensation under the Vaccine Act. 941 F3d 1351 (Fed Cir 2019). As background, on August 27, 2013, the Boatmon petitioners filed a petition for compensation under the Vaccine Act, alleging that their son, J.B., died as a result of the diphtheria-tetanus-acellular pertussis (“DTaP”), Haemophilus influenzae type B (“HiB”), inactivated poliovirus (“IPV”), rotavirus, and pneumococcal conjugate vaccines administered to him on September 2, 2011. Boatmon v Secretary of Health & Human Services , No. 13-611V, 2017 WL 3432329 at 1 (Fed Cl Spec Mstr July 10, 2017). J.B. died one day after receipt of the vaccinations and the cause of death was determined to be Sudden Infant Death Syndrome (SIDS). The special master found for the petitioners, accepting their theory that vaccines, like mild infections, were an exogenous risk factor for causing SIDS under the Triple Risk Model and did so by stimulating the production of cytokines, which suppressed the infant’s respiratory response system. The special master’s decision was the first non-Table claim under the VICP to find that vaccines can cause SIDS.

The Department of Health and Human Services sought review of the special master’s decision on the basis that he committed legal error by applying the incorrect legal standard and by finding essential facts based on statistical evidence alone Boatmon v Secretary of Health & Human Services , 138 Fed Cl 566, 571 (2018). The Court of Federal Claims reversed the entitlement decision, concluding that the special master committed legal error in ruling for petitioners. Specifically, the Court found that the special master applied a lower burden of proof than required by the Act, failed to acknowledge other VICP cases that reached opposite conclusions based on similar evidence, made no attempt to distinguish Boatmon from those cases, and embraced a theory that has not been accepted by any other experts in the field of SIDS research.

The Federal Circuit affirmed the judgment of the Court of Federal Claims but based on a different rationale. Boatmon v Secretary of Health & Human Services , 941 F 3d 1351 (Fed Cir 2019). The Federal Circuit held that the special master applied a lower standard than what is required with respect to the petitioners’ medical theory of causation; that is, a theory of vaccine causation that is merely “plausible” or “possible” is not sufficient under the Act. Further, examining the evidence upon which the special master based his decision, the Federal Circuit concluded that petitioners’ extension of the Triple Risk Model theory to include vaccinations as an exogenous risk factor as a cause of SIDS is not a sound and reliable medical theory as required by Althen prong one. Further, because petitioners failed to present a sound and reliable theory of how vaccinations can cause SIDS, they necessarily failed to establish a logical sequence of cause and effect that the vaccinations caused or contributed to the infant’s death from SIDS ( Althen prong two).

Another important issue that has been litigated in the VICP is ascertaining when a claim for an alleged vaccine-related injury begins to run. In 2011, the Federal Circuit issued an en banc decision holding that the NCVIA’s statute of limitations begins to run on the date of occurrence of the first symptom or manifestation of onset of the injury, reversing a panel decision that concluded the limitations period does not run until the medical community at large objectively recognizes a causal relationship between the vaccine and the injury (i.e. “discovery rule”). Overruling prior precedent, the Federal Circuit also held that equitable tolling applies to the NCVIA. Equitable tolling is a principle of law stating that the statute of limitations shall not bar a claim in cases in which the petitioner, despite due diligence, could not or did not discover the injury until after the expiration of the limitations period. Observing that equitable tolling is to be used “sparingly” in federal cases (such as cases involving deception, or the timely filing of a procedurally defective pleading), the Federal Circuit held that unawareness of a causal link between an injury and the administration of a vaccine is not a basis for application of equitable tolling under the NCVIA and declined to apply equitable tolling in petitioner’s case to forgive the untimely filing of her petition under the NCVIA. The issue of whether attorneys’ fees and costs were available in this untimely filed case was appealed to the U.S. Supreme Court, which affirmed the judgment of the Federal Circuit, finding that a person whose petition under the NCVIA is dismissed as untimely may recover an award of attorneys’ fees and costs if certain requirements are satisfied.

For purposes of judicial economy (when the process is agreed upon by the parties), special masters may opt to adjudicate several cases (typically involving claims that the same alleged injury was caused by the same vaccine) in a consolidated or “omnibus” proceeding. The results of some of these proceedings (e.g., hepatitis B vaccine and demyelinating diseases discussed under Hepatitis B Virus Vaccines, below) have been controversial given the scientific literature.

One such omnibus proceeding early in the vaccine injury program involved tuberous sclerosis complex (TSC), a genetic disorder characterized in many cases by classical skin lesions, growths (tubers), and other structural changes in the brain, causing seizures and intellectual disabilities. Many of the claims alleging seizure onset within a VIT time frame were litigated as a group to determine whether DTP vaccine significantly aggravated the preexisting TSC condition. Based in part upon advances in magnetic resonance imaging in the 1990s, ^, the presiding special master ruled that the number and presence of tubers in the cerebral cortex, not the timing of DTP vaccination, ultimately determine clinical outcome. The special master’s decision denying compensation was affirmed on appeal in Hanlon v Secretary of Department of Health and Human Services , Turner v Secretary of Department of Health and Human Services , and Flanagan v Secretary of Department of Health and Human Services.

To date, the omnibus proceeding that has garnered the most public interest and scrutiny is the omnibus autism proceeding (OAP). Interest and concern about vaccines and autism started with the publication of a 1998 case series by Andrew Wakefield and colleagues in the Lancet suggesting that the MMR vaccine was associated with autism. Little attention was paid in the United States until the following year, when a congressionally mandated FDA review of mercury in biological products showed some vaccinated infants were receiving ethylmercury in excess of one federal safety guideline established for methylmercury, the more extensively studied form of organic mercury. Attention then became focused on thimerosal, an ethylmercury compound used for decades in the formulation of many routinely administered childhood vaccines to prevent bacterial and fungal contamination.

In the early 2000s, individual and class action lawsuits were filed in state courts alleging autism or autism spectrum disorder caused by thimerosal-containing vaccines and/or the MMR vaccine (which does not contain the preservative). The plaintiffs often argued that they were not required to subject to the NCVIA’s exhaustion requirements with respect to claims concerning thimerosal. Multiple large, well-controlled epidemiologic studies all failed to find an association between thimerosal-containing vaccines and autism. The IOM concluded in its 2004 report that the body of scientific evidence favors rejection of a causal relationship between MMR and thimerosal-containing vaccines and autism. A 2012 IOM report reiterated the same conclusion for MMR vaccine and autism, and did not again examine thimerosal-containing vaccines as part of its review.

The VICP began receiving claims alleging autism or autism spectrum disorder caused by MMR or thimerosal-containing vaccines in late 2001. As the number of claims grew to nearly 5000, the Office of the Special Masters established the OAP to adjudicate these cause-in-fact cases in a consolidated manner.

The Petitioners Steering Committee (PSC) put forth six test cases to represent two separate theories of general causation. See uscfc.uscourts.gov/autism-decisions-and-background-information. Under the first theory (“Theory 1”), petitioners argued that MMR vaccine and thimerosal-containing vaccines (TCVs) combine to cause autism. Under the second theory (“Theory 2”), petitioners argued that thimerosal-containing vaccines alone cause autism.

The Office of the Special Masters conducted extensive evidentiary hearings, reviewing 939 medical articles, 50 expert reports, and testimony from 28 experts. The hearings produced more than 5000 pages of transcripts and well over 7000 pages of post hearing briefs. The three presiding special masters issued decisions finding that petitioners had not met their burden of showing by preponderant evidence that MMR vaccine, either alone or in combination with TCVs, can cause autism and/or autism spectrum disorder, much less that they did so in any of the test cases. Petitioners appealed the three Theory 1 cases to the Court of Federal Claims without success. Petitioners further appealed two of the three Theory 1 cases to the Federal Circuit. ^, In both cases, the Federal Circuit ruled in favor of the government, upholding the lower determinations that petitioners had not proven their theory of causation by a preponderance of the evidence. Petitioners did not pursue appeals in the Theory 2 cases.

MODIFYING THE VACCINE INJURY TABLE

The Secretary of HHS has the authority to modify or amend injuries listed in the VIT (and QAIs) in consultation with the ACCV and after opportunity for public comment. Such changes apply only to cases filed after the effective date of the changes. In 1993, Congress provided a mechanism for the Secretary to add to the VIT “new” vaccines recommended by CDC for routine administration to children based on the effective date of the excise tax for that vaccine. Table 85.5 summarizes changes to the VIT through June 1, 2021.

Separate efforts by the VICP to modify the initial statutory VIT and QAIs began with publication of the two congressionally mandated IOM reviews in 1991 and 1994, respectively. With a few exceptions, the approach by the VICP was straightforward: If the IOM concluded that there was evidence that a condition was “causally related” to a covered vaccine, it was added to the VIT or left on the VIT. However, if there was no proven evidence of an association, that condition was removed. Publication of final rules in 1995 and 1997 setting forth these modifications was the final step in a 3-to-4-year process for each set of changes involving ad hoc scientific panel reviews by the NVAC, mandatory ACCV reviews, and a 180-day public comment period, including a public hearing.

The first set of changes, effective March 10, 1995, was controversial. Hypotonic-hyporesponsive episode and residual seizure disorder were removed as presumptive injuries for DTP vaccines under the VIT, and the definitions of encephalopathy and residual seizure disorder were modified in the QAIs. At that time, the only exception to using the IOM’s conclusions to guide changes to the VIT was encephalopathy/encephalitis following DTP vaccine, which had been proposed for removal, but was left on the Table in response to advice from the ACCV. The ACCV recommended that claims of acute encephalopathy of unknown etiology within 3 days (72 hours) of DTP vaccination should continue to receive a presumption of causation, but that the definition in the QAIs needed to be more clinically precise. A subsequent 1994 analysis by the IOM of a 10-year follow-up to the British National Childhood Encephalopathy Study fell short of answering the ultimate question of whether DTP vaccine causes permanent brain damage, even though many investigators over time had failed to find a link based on epidemiologic and other scientific evidence.

For the most part, DTP injury claims under the original VIT were filed on behalf of children and adults with chronic encephalopathy of unknown cause manifesting as developmental delay or the onset of seizures during the first year or two of life. Overall, no specific cause is ever determined for as many as 40% of the cases, with most thought to be caused by migrational abnormalities of fetal brain development or metabolic or “genetic” conditions not identifiable by current technology. ^, For petitioners to successfully pursue a VIT claim, the presumptive condition and time frame must be established and there is not a preponderance of the evidence that the condition is due to factors unrelated to the vaccine, which do not include “idiopathic” or unknown causes.

As for seizures, nearly half of the early DTP filings involved the initial onset of seizures in an otherwise healthy infant. Significant numbers of seizure claims were being compensated using the original statutory version of the VIT. Often the fever commonly associated with DTP vaccine would serve as the triggering event for the onset of seizures in a child predestined to have epilepsy. Alternatively, a Table seizure condition would be found in a child with cryptogenic (idiopathic) infantile spasms if the onset of myoclonic seizures was within 3 days of DTP vaccination. This resulted in compensated cases despite controlled epidemiologic studies showing the condition to be non–vaccine-related. ^,

Claims alleging death caused by DTP vaccine also proved challenging in the program’s early years. Approximately half were attributed to sudden infant death syndrome (SIDS), with compatible histories and forensic findings in accordance with the 1989 National Institutes of Health consensus definition. However, because the cause of SIDS remains unknown, these cases were initially viewed as “idiopathic” by the court and could not be used by the government to prove that a factor unrelated to the vaccine caused the death. Furthermore, based on testimony concerning events preceding the death, the court sometimes concluded that an encephalopathy or hypotonic-hyporesponsive episode was present before death and awarded compensation. More recently, however, in off-Table claims the Federal Circuit has held that special masters may consider evidence of SIDS (alternative cause) in determining whether petitioner established a prima facie case.

The second set of changes to the VIT proved less controversial and was based, in large part, on the 1994 IOM report covering the five remaining original VICP vaccines, as well as Hib, HBV, and VZV vaccines, which were also added to the VICP because all were recommended by the CDC for routine administration to children. The other modifications, effective March 24, 1997, included the addition to the VIT of thrombocytopenia for measles-containing vaccines and brachial neuritis for tetanus-containing vaccines, the removal of residual seizure disorder under MMR vaccines, and the creation of a provisional or placeholder category on the VIT for vaccines newly taxed and satisfying the CDC recommendation requirement. Only after notice to the public with publication in the Federal Register would the newly added vaccine have a separate and distinct listing on the VIT, including the addition of a Table condition when appropriate.

As with the 1995 rulemaking, proposed VIT changes developed by the Secretary paralleled the IOM conclusions for or against causation with two exceptions: the Secretary did not add GBS following OPV and following tetanus-containing vaccines. The IOM’s OPV conclusion was based largely on a Finnish study following a national OPV campaign. A subsequent U.S. study (therefore not considered by the IOM) showed no evidence of an increase in GBS following OPV administration. Further doubt was cast when one of the Finnish study’s coauthors wrote a letter noting that it was not their intention to claim that OPV was causally related to GBS because the data could be interpreted more than one way.

The question of GBS and tetanus-containing vaccines was even more difficult to decide. The IOM conclusion was based on case reports, particularly of one person who experienced three episodes of GBS, each within weeks following tetanus vaccination. The fact that he had other non–vaccine-related episodes made him immunologically unique (notably, in the 2012 IOM report, that case report was reexamined and the patient was found to have CIDP, not GBS). Population studies, in contrast, showed no evidence that GBS incidence is higher in people receiving tetanus vaccine compared with the background rate. ^, Because there was no evidence of increased incidence overall, it was thought that petitions involving GBS following tetanus-containing vaccines should continue to require proof of causation, and, therefore, GBS should not be added to the VIT.

Since 1997, the VIT has been modified further (see Table 85.5 ). The general category of rotavirus vaccines was added effective October 21, 1998, following licensure of RotaShield, a tetravalent rhesus-based rotavirus vaccine. RotaShield was subsequently withdrawn from the market by the manufacturer in October 1999, after epidemiologic studies confirmed an association between the vaccine and cases of intussusception, a potentially life-threatening bowel obstruction that occurs in infants. In July 2002, a final rule was published adding intussusception as a listed injury to the VIT under a second category of rotavirus vaccines (i.e., live, oral, rhesus-based). In addition, pneumococcal conjugate vaccines were made a separate and distinct category on the VIT. The second category of rotavirus vaccines (i.e., live, oral, rhesus-based), with the associated injury of intussusception, was removed from the VIT, effective November 10, 2008. This was a technical change, since the 3-year filing deadline for all such claims had long since passed given that the RotaShield vaccine was withdrawn from distribution in the United States in 1999. The general category of rotavirus vaccines with “no condition specified” was not affected.

Beginning in 2004, hepatitis A and trivalent influenza, meningococcal (conjugate and polysaccharide) and HPV vaccines were added to the VIT in the placeholder category for “new” vaccines recommended by CDC for routine administration to children. However, the vaccines were subsequently moved to separate and distinct categories in the VIT, effective July 22, 2011. On November 12, 2013, all seasonal influenza vaccines (e.g., quadrivalent influenza vaccines) were added to the VIT in the placeholder category for “new” vaccines. Subsequent to the licensure of two new rotavirus vaccines in 2006 and 2008, new evidence from postmarketing studies suggested intussusception was causally associated with Rotarix and RotaTeq, although much more rarely than had been the case with RotaShield. ^– Effective July 23, 2015, intussusception was added to the VIT as a presumptive injury for rotavirus vaccines, but only following the first two doses. ^a

In 2016, Section 3093(c) of Public Law 114-255, the 21st Century Cures Act (Cures Act) amended 42 USC §§ 300aa–14(e)-(f) of the NCVIA to expand the types of vaccines covered under the Act to include vaccines recommended by the CDC for routine use in pregnant women (subject to an excise tax by federal law), and to amend the Act’s one petition rule as it applies to vaccines administered to pregnant women by providing that “both a woman who received a covered vaccine while pregnant and any child who was in utero at the time such woman received the vaccine shall be considered persons to whom the covered vaccine was administered and persons who received the covered vaccine.” 42 USC § 300aa-11(f)(1).

In 2011, the IOM reported the results of its reviews concerning the evidence with respect to causal associations between 12 VICP-covered vaccines (in various combination) and 158 adverse events. After release of its report in 2012 (2012 IOM report), medical staff at the Health Resources and Services Administration (HRSA) and the CDC reviewed the IOM’s conclusions, as well as other medical and scientific literature not contained in the IOM report. Based primarily on the IOM’s review, the work of nine HHS workgroups that reviewed the IOM findings, and consideration of the ACCV’s recommendations, a final rule to substantially revise the VIT was published on January 19, 2017 and was effective on March 21, 2017. ^b-

The 2017 final rule included numerous revisions to the VIT. It added two injuries, shoulder injury-related vaccine administration (SIRVA) and vasovagal syncope, based on the IOM’s findings that the scientific evidence convincingly supports a causal relationship between an injection-related event and deltoid bursitis and syncope. 80 FR 45135 (July 29, 2015). Thus, the final rule included SIRVA and vasovagal syncope as injuries for all intramuscularly injected vaccines on the VIT, provided they met the timeframes for a presumptive injury, as well as the QAI. Further, the rule revised the QAI for anaphylaxis and added it as an injury for the varicella, seasonal influenza, meningococcal, and HPV vaccines based on the IOM’s findings that the scientific evidence convincingly supports a causal relationship. Additionally, stemming from the IOM’s findings, the final rule added vaccine-strain measles viral disease in an immunodeficient recipient to the VIT as an injury for vaccines containing the measles virus, and disseminated vaccine-strain viral disease and varicella vaccine-strain viral reactivation as injuries for varicella vaccines.

Following the recommendation of the ACCV, the final rule also added the injury of GBS to the VIT for seasonal influenza vaccines. The IOM found the evidence inadequate to accept or reject a causal relationship between seasonal influenza vaccines and GBS. However, studies have demonstrated a causal association between some nonseasonal influenza vaccines—the monovalent 2009 H1N1 vaccine and the 1976 swine flu vaccine—and GBS. To date, the H1N1 antigen has been included in all seasonal influenza vaccines beginning with the 2010–2011 flu season. Acknowledging that seasonal influenza vaccine formulations, unlike other vaccines, include multiple antigens that change from year to year, and enhanced surveillance activities to detect the incidence of GBS that occurred during the 2009 H1N1 pandemic may not occur with each virus strain change, the ACCV recommended that the Secretary add GBS to the VIT consistent with one of the ACCV’s Guiding Principles: where there is credible evidence to both support and reject a change to the VIT, the change should, whenever possible, be made to the benefit of petitioners.

Finally, the final rule included many organizational and structural changes to the VIT and QAI designed to increase clarity and scientific accuracy. For example, it added definitions for terms that had previously been on the VIT or QAIs but were undefined, such as encephalitis and immunodeficient recipient; it updated some of the QAIs to address certain changes in scientific nomenclature; it streamlined the VIT with the deletion of redundant wording; and it changed the category of “trivalent vaccines” to “seasonal influenza vaccines” to cover all seasonal influenza vaccines, including trivalent influenza vaccines, in one category. A Final Rule, published on January 21, 2021 (86 FR 6249), which would have removed SIRVA and vasovagal syncope as presumptive injuries under the VIT, and removed Item XVII (i.e., provisional or placeholder category) was rescinded on April 22, 2021 (86 FR 21209) and never took effect.

MEDICAL REVIEW OF CLAIMS

Most claims filed under the original NVCIA had some clinical outcome in temporal relation to vaccination that varied from the expected side effects of crying, fever, and local swelling to much more serious acute and chronic illness. The claims generally represent a database of possible vaccine-related events, although only a small percentage of serious outcomes are thought to be actually caused by vaccines after VICP medical staff review. Some of the more relevant allegations are reviewed here.