Immunization information from the Internet

April 2004

Use of the Internet for obtaining and evaluating information, including medical information, has increased significantly in past years. Included in the vast array of medical information available on the Internet are various data, opinions and testimonials about the benefits and potential dangers of pediatric immunizations. Clinicians and the lay public can easily obtain information about the benefits and adverse effects of immunization from well-known Web sites such as those from the CDC and the AAP. However, information describing a lack of benefit and “toxic effect” of routinely recommended pediatric immunizations can easily be found as well. How can clinicians respond and communicate with caregivers who refuse immunizations for their children because of this information? Causes of immunization noncompliance are multifactorial. Objections for religious or philosophical reasons account for less than 1% of nonvaccinated pediatric population (1998 data), but this may be increasing because of greater Internet availability.

Risk communication

An area of study referred to as risk communication has most often been applied to efforts to reduce high-risk health behavior. Risk communication may also be applied to immunization risk, although unique challenges exist with vaccine risk communication, because of the relatively smaller risks of serious adverse effects and because of ill-defined estimates or uncertainty of specific risks that attract widespread attention and concern.

Risk communication between caregivers and clinicians is likely to be most beneficial when the following are met or acknowledged:

• Quantification of risk by scientific means.
• Acknowledgement of uncertainty when necessary.
• Trust in the exchange of information.
• Active listening and discussion, including a nonjudgmental and empathetic approach.
• An appreciation for individual differences of risk perception.
• Clinician’s appreciation of the level of understanding of immunizations (benefits, risks) by caregivers.
• Use of factual information by the clinician at a level commensurate with the caregiver’s ability to understand.

The Red Book (AAP, 26th edition) suggests that clinicians seek out information from caregivers about their cultural, health, religious or philosophical beliefs which may affect immunization acceptance. Additional information about caregiver knowledge or experience with immunization adverse effects may also be helpful. By use of these means clinicians may be more likely to dispel caregivers’ belief of inaccurate information and more able to establish credibility with them.

Numerous factors may form or sway caregiver perception or acceptance of risk. Personal testimonials were among the most commonly used methods of describing potential adverse effects of vaccines among a survey of various Internet sites supported by parent groups (Hibbs). Such personal and anecdotal “evidence” for vaccine adversity can be compelling, particularly if accompanied by pictures on Internet sites. Other factors may include lack of knowledge of disease morbidity and complications or epidemiology (especially with diseases of rare occurrence in recent years), personal experiences with vaccine safety issues, beliefs in the modern health care system and the pharmaceutical industry and education level. Understanding the sources of vaccine information used by caregivers is additionally important when communicating about risk. Use of information sources not grounded in scientific principles, the news media or alternative health information may all affect acceptance of vaccine use. Clinicians discussing vaccine issues with caregivers should seek out their sources of information.

Internet sites

Communicating with caregivers about how to assess a site’s credibility is important for those who use the Internet for obtaining information on vaccines and immunization. Internet users should be able to assess the accuracy of information on a Web site. The site should clearly state who or what organization is responsible for the information and a means for a site visitor to contact the Webmaster. Specific factual or scientific information should be referenced and the specific references listed, and the information listed should be up to date, with the revision dates given. The credentials of the Web site authors should be stated. The information contained in the Web site should offer more than one perspective (ie, evidence for beneficial effects as well adverse effects) and should attempt to be unbiased. Web site viewers should be aware of ulterior motives of the site, such as indirect commercial advertising. It is wise for clinicians to consider – and explain to caregivers – that nearly anyone can establish a Web site and post information, regardless of scientific accuracy. Clinicians can assist caregivers in assessing the validity and usefulness of Web sites offering vaccine information (www.immunizationinfo.org/parents/evaluatingWeb.cfm).

The Internet contains numerous Web sites discounting the usefulness of traditional pediatric immunizations while emphasizing the dangers. The purpose of one site (Vaccination Liberation, www.vaclib.org) is to “reveal the myth that vaccines are safe and effective” and “to preserve our right to abstain.” This site lists a contact name, e-mail address and phone number. Various links within the site provide an abundance of information alluding to the dangers of vaccinations – however, stated claims and “factual” information are not supported by referenced or peer-reviewed material. Quotes and news stories are commonly supplied. It is not hard to imagine a parent or caregiver developing doubts about routine immunization after viewing this site.

Another site (www.relfe.com/vaccine.html) is a Web site link from a commercial Web address with the mission statement “to replace the existing systems for health, education, government, money and business with systems which are in harmony with nature.” The link is written by an individual, although the individual’s credentials are not given. The individual’s listed Web site link is inoperable. Additional commercial advertisements follow the listed text. The editorial text alludes to the lack of efficacy and dangers of immunizations and includes 10 “myths” on immunizations. One “myth,” that “vaccines are very effective … or are they?” discusses this immense subject in four short paragraphs and concludes that “evidence suggests that vaccination is an unreliable means of preventing disease.” References are listed to support these claims; some are from peer-reviewed medical journals, while others are incomplete references from unclear sources. Counter-evidence from additional peer-reviewed journals or texts on the benefit of disease prevention are not presented. It is highly doubtful that such an obviously biased editorial or essay would be published in a peer-reviewed medical journal. Additional Web sites listed for more information do not include sites generally accepted by the medical community, such as those from the CDC or AAP.

The Internet offers a vast amount of information on immunizations to clinicians and caregivers. Much of this information is biased strongly against the use and beneficial effects of routine pediatric immunizations, and it is not hard to imagine a parent or caregiver developing doubts or concerns about immunization of their child. Using risk communication strategies, clinicians may be able to gain an appreciation of caregiver concerns, provide scientifically based accurate information on disease epidemiology and morbidity and provide balance to negatively biased information on immunizations, to allow caregivers to more fully understand the potential benefits and adverse effects of pediatric immunizations. Clinicians may consider scheduling office appointments specifically to discuss immunization issues, should caregivers express concerns. Offering immunization information to caregivers to review prior to the visit may be additionally helpful (see table below).

For more information:

• National Vaccine Advisory Committee. Report of the NVAC Working Group on Philosophical Exemptions. Atlanta: CDC/National Vaccine Program Office; 1998:1.
• Hibbs BF. Internet Web pages’ perceptions of vaccine pharmacoepidemiology research: an analysis of vaccine safety concerns. Abstract 129. Abstracts of the 13th International Conference on Pharmacoepidemiology. Pharmacoepidemiol Drug Saf. 1997;6(suppl 2):S60.
• Stein M, Pickering B, Tanner JL, et al. Parental refusal to immunize a 2-month-old infant. J Dev Behav Pediatr. 2000;21:432-436.
• Chen RT, Hibbs B. Vaccine safety: current and future challenges. Pediatr Ann. 1998;27:445-455.