Informed Consent in Vaccination
The American Medical Association defines informed consent as "a process of communication between a patient and physician that results in the patient's authorization or agreement to undergo a specific medical intervention."1 The principle behind this process reflects respect for patient autonomy, and it is particularly relevant to the administration of vaccines. The Declaration of Helsinki, the highly-regarded international guidelines for research on human subjects, states that "considerations related to the well-being of human subjects should take precedence over the interests of science and society."2 While this statement was written with respect to biomedical research, it has been argued that a similar principle should be applied to vaccine policy. Some bioethicists, clinicians, and others argue that the decision to vaccinate should always be left to patients (or parents, in the case of children), despite years of evidence that mass immunization confers additional protection to the communities by reducing the spread of infectious disease--a phenomenon known as herd immunity. Regardless, the principle of informed consent requires that a patient (or his/her parents, in the case of children) understand the risks and potential benefits of a particular vaccine before receiving it.
Vaccine information sheets and signed consent forms
Because vaccination in the U.S. is viewed as routine, discussions between physicians and parents about immunization may be truncated, if not omitted entirely. While not a replacement for a meaningful dialogue between healthcare providers and parents, information statements produced by the Centers for Disease Control and Prevention are required to be made available to parents whose children are vaccinated. In addition to its ethical importance, consent has legal meaning as well, as parents are responsible for the medical decisions involving their minor children. More controversial is what role, if any, "assent"--the approval of the child, independent of the parent's--should play in the decision to administer vaccines.
While much of the discussion involving vaccine policy focuses on pediatric vaccination issues, an increasing number of vaccines are available and recommended to older individuals. In the case of influenza and pneumococcal conjugate vaccines, recommended for elderly populations, it has been argued that a signed consent form--a common strategy for obtaining informed consent--does not necessarily confirm that the patient understand the risks and benefits of the vaccines.3 In fact, the requirement for signed consent forms for these vaccines may hinder efforts to immunize older and more susceptible populations, leading to unnecessary deaths from these increasingly preventable diseases, according to researchers.
HPV vaccine and consent
2006 marked the introduction of Gardasil, a vaccine against two strains of human papillomavirus (HPV) that are responsible for the majority of cervical cancer cases in the U.S. and worldwide.4 It also provides protection against two addition HPV strains that cause most cases of genital warts. Since the virus is spread sexually, the vaccine is most effective when given before sexual activity begins. Based on clinical trial results, the Advisory Committee on Immunization Practices (ACIP) at the Centers for Disease Control and Prevention (CDC) recommended that Gardasil be given to girls between the ages of 11-26 years. The vaccine can be administered as early as 9 years of age, based on the judgment of the physician.5 In 2009, a competing HPV vaccine, Cervarix, was licensed in the United States. This vaccine was approved for protection against the same cancer-causing viruses as Gardasil (without the genital wart protection). Cervarix is recommended for the same population of adolescents and young women as Gardasil.6
The introduction of HPV vaccines in the United States has been contentious. Some observers have feared that it may be difficult to persuade parents to vaccinate their 11-year old daughters against a sexually transmitted disease. Critics have suggested that the vaccine may force parents to discuss sex at an earlier age than they might desire, or that by consenting to Gardasil, parents may be tacitly encouraging their daughters to engage in early sexual behavior. Evidence supporting such changes in risk behaviors following HPV vaccination has not been observed to date.
Despite these early concerns, studies have shown that less than a quarter of parents are likely to deny consent for their daughters' vaccination against HPV. Those who do often change their minds in favor of Gardasil when presented with more information about HPV and its association with to cervical cancer.7 Additionally, a recent study published in Vaccine found particular importance for the physician's recommendation in parental decision-making regarding HPV vaccination. Researchers found a four-fold increase in parental support for the vaccine after receiving a strong doctor recommendation compared to a weaker endorsement.8
Unique aspects of HPV vaccines raise additional ethical debates. For example, should a well-informed young woman (still a minor) be permitted to received the vaccine without her parents' consent, either unbeknownst to them or against their explicit wishes? The answer may depend, in part, on the age of the minor, as most agree that the views of a 17-year-old regarding medical decisions should receive more respect than those of an 11-year-old, for example. According to one study, parents who support teenagers' right to receive the HPV vaccine without parental consent do so to encourage responsible behavior, protect adolescents from ill-informed parents, and respect their confidentiality. Parents who support the requirement for parental consent cite the desire for adult responsibility in a child's health, fear of erosion of parental rights, and respect for cultural and moral values.9
Informed consent in research
Informed consent becomes particularly important in vaccine research. Many bioethicists agree that investigators should follow the ethical principle of the "practical imperative," which states that a people cannot be used simply as means, but rather that they should be treated as ends in and of themselves.10 There is consensus that all participants in a randomized vaccine clinical trial, as with any clinical research, must be fully aware of all possible risks in addition to any potential direct benefits of enrolling.
Several obstacles often hinder appropriate informed consent in research. Among them, consent forms can be complex and poorly designed, researchers may not spend enough time with participants, and research staff may not communicate in a culturally or linguistically appropriate manner.11
-- By Ben Kleifgen, Temple University School of Medicine; Updated July 2010
For more information
• CDC Vaccine Information Statements: http://www.cdc.gov/vaccines/pubs/vis/default.htm
1 American Medical Association website: http://www.ama-ssn.org/ama/pub/category/4608.html Accessed 20 July 2007.