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Lax vaccination policies heighten risk for vaccine-preventable disease outbreaks
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Between December 2014 and February 2015, 125 measles cases were confirmed among U.S. residents in connection with the California-Disneyland measles outbreak — the largest vaccine-preventable disease outbreak that the United States has experienced in years, according to MMWR.
Through the end of June 2015, 178 measles cases have been reported in 24 states and the District of Columbia. A Washington state woman who was immunocompromised from medications treating other chronic health conditions died from measles in the spring, the first such measles death in the U.S. in 12 years. The majority of those infected have not received the measles vaccine.
Some of these cases were too young to be vaccinated but many were intentionally unvaccinated due to personal beliefs. The first identified case occurred in an unvaccinated individual, and most of the subsequent cases were unvaccinated also.
While a main source of the outbreak was never identified, CDC officials believe it was brought into the U.S. from an international traveler, due to matched disease genotypes with a recent outbreak in the Philippines, 14 other countries and six states within the same time period.
Photo courtesy of University of Alabama at Birmingham
“The Disneyland outbreak exemplified many lessons about recent outbreaks of measles and other vaccine-preventable diseases. Measles is extremely contagious to those who are unvaccinated or otherwise vulnerable,” Robert Schechter, MD, section chief of the California Department of Public Health Immunization Branch, said during an interview with Infectious Diseases in Children. “For the unimmunized adults in the outbreak, decisions made to decline immunization had their ramifications decades later. Consequences linger.”
Infectious Diseases in Children spoke with several experts about the heightened risk for other vaccine-preventable outbreaks without stricter vaccination policies, the questions regarding the laws and policies surrounding vaccination debates and the strategies pediatricians are utilizing to maintain, as well as increase, vaccination rates among their patients.
Lenient laws
Experts agree that the measles outbreak in Disneyland highlights the end result of lax vaccination laws.
“We have recently seen the heightened risk for a vaccine-preventable disease outbreak without stricter vaccination policies,” David W. Kimberlin, MD, the Sergio Stagno Endowed Chair in Pediatric Infectious Diseases, and co-director of the division of pediatric infectious diseases, at the University of Alabama at Birmingham, said during an interview with Infectious Diseases in Children.
With low rates of vaccination comes opportunities for importation of diseases that are otherwise preventable. Not only are infants who are not able to be vaccinated susceptible, but the population of children and adults who are immunocompromised and are medically prohibited from vaccination also are at risk.
“When there is importation of a vaccine-preventable disease, and the disease gains exposure within a community that has relatively low vaccination rates for that particular infection, it is like throwing a match on dry leaves — the flame will catch and it will spread quickly,” Kimberlin said. “From a societal standpoint, we need to do the responsible thing and keep others who are not able to be vaccinated from getting sick in the first place. Vaccines save lives.”
José R. Romero, MD, Section head and Horace C. Cabe professor of Infectious Diseases at Arkansas Children’s Hospital, and also a member of the Infectious Diseases in Children Editorial Board, said that while there have not been any other recent outbreaks of the magnitude of the Disneyland event, pertussis outbreaks that have occurred in California and in other parts of the country in recent years also may be associated with the lack of vaccination.
“However, there have been discussions suggesting they may be due to waning immunity based on the current pertussis vaccines, so this needs to be addressed,” Romero said during an interview. “The Disneyland measles outbreak is a sentinel event and a clarion call for physicians and parents to rethink their approach to vaccines in the near future.”
Walter A. Orenstein, MD, professor and associate director of the Emory Vaccine Center, professor in the department of medicine and the division of infectious diseases, and director of influenza pathogenesis and immunology research center at Emory University School of Medicine, agrees that while there has been a resurgence of pertussis, this appears to be more of a problem of waning vaccine-induced immunity than a failure to vaccinate. Yet, some of the largest outbreaks of pertussis have occurred in areas with low vaccination coverage.
“Measles is the ‘canary in a coal mine’ — it is at the top of the list of contagious vaccine-preventable diseases and when immunization rates become low, the population becomes vulnerable,” Orenstein said. “The highest year for measles in 20 years occurred in 2014, and thus far this year, we have had a substantial number of cases giving us worry that measles could re-establish itself as endemic and circulating in the United States. The other big concern with measles is how expensive it is to try and contain outbreaks, so it would certainly be best if we could get higher immunity levels in our population, which would decrease the chances of spread if any importations come about.”
Debunking autism/vaccine link for good
The unfortunate resurgence of these vaccine-preventable diseases has been caused by parents not vaccinating their children due to the continued concerns over vaccines causing autism.
“We need to debunk and finally put away the connection between autism and vaccines,” Aaron E. Glatt, MD, hospital epidemiologist at South Nassau Communities Hospital on Long Island and a Spokesperson for the Infectious Diseases Society of America, told Infectious Diseases in Children. “It is a shame that people still unfortunately believe that there is a connection. As best as science can ever possibly prove, that has been debunked. It is like arguing that the earth is flat: It is almost impossible to prove that the earth is round if one does not want to believe that the earth is round. We have done everything possible to prove that autism is not at all related to vaccination. Yet, when people are asked why they do not want to get vaccinated, a high percentage still respond with the autism concern.”
In a study published in JAMA in April, researchers sought to examine the possible association between autism spectrum disorders and measles-mumps-rubella vaccine status among 95,727 U.S. children with older siblings with and without autism.
According to study results, 84% of children with older siblings who did not have autism received one or more doses of the MMR vaccine at age 2 years, and 92% received the vaccine at age 5 years. Among those with older siblings who had autism, 73% received one or more doses of the vaccine at age 2 years, and 86% received one or more doses at age 5 years.
Of the children with older siblings, 1.04% were diagnosed with autism of which 2.01% had an older sibling with autism. Of those with older siblings with autism, 6.9% had autism when compared with 0.9% of those with a sibling who did not have autism (P < .001).
“In this large sample of privately insured children with older siblings, receipt of the MMR vaccine was not associated with increased risk for autism, regardless of whether older siblings had autism,” the researchers wrote. “These findings indicate no harmful association between MMR vaccine receipt and autism even among children already at higher risk for autism.”
Glatt noted the resurgence of these vaccine-preventable diseases is essentially preventable by universal vaccination.
“We have eradicated smallpox, but only through vaccination,” he said. “Smallpox killed hundreds of millions of people in the past, and now there is zero smallpox in the world. Essentially, polio has been eradicated in North America with only a few countries in the world harboring indigenous polio. We have the ability to eradicate fatal and serious childhood illnesses by universal vaccination and anything short of that is unfortunately putting many children at risk.”
Enactment of stricter policies
As mandated by the most recent vaccination law enacted in California, beginning in 2016, parents who refuse to vaccinate their children cannot enroll them in public school or any other educational facilities where the law states a child must be vaccinated before attending. Children with medical reasons shall remain exempt as well as those enrolled in a home-based private school or those enrolled in an independent study program.
In Mississippi and West Virginia, where vaccination exemptions are limited to medical reasons, attempts to allow religious or personal belief exemptions have failed. Vermont also removed its personal belief exemption this year, leaving only medical and religious exemptions in place.
“In West Virginia, school vaccination laws were revamped this past legislative session. Requests for medical exemptions are now reviewed, or can be reviewed,” Andy Baker-White, JD, MPH, instructor at the Michigan Public Health Training Center of the University of Michigan, said during an interview. “This might be something that occurs more often down the road, with medical exemptions reviewed by the state department of health or some other entity.”
Baker-White said some states are testing the idea of making the vaccination rates of schools public, so that parents can be informed of vaccination coverage for their child’s school.
“Here in Michigan, the newspapers have published these numbers. I was recently looking at the rates for my daughter’s preschool, and was shocked at the number of kids [without vaccinations] who do not have exemptions at the preschool,” he said. “It has sparked a discussion for the preschool board about whether we need to take additional steps when it comes to parents who want exemptions for their children.”
In other states, bills have been introduced that would give parents notice when an unvaccinated child enrolls in their child’s school via a note sent home from the school principal stating that there is a child or a number of children who are not vaccinated.
Diane C. Peterson, associate director of immunization projects for the Immunization Action Coalition, has tracked vaccination exemption-related legislation for nearly 7 years.
“It started with people wanting to broaden the ability for parents to choose to opt out of vaccinations that were required for school or day care,” Peterson said during an interview. “For example, all states in the country with the exception of three states, now that California has joined West Virginia and Mississippi, have exemptions permitted for religious reasons, and there are 18 states that have exemptions due to parents’ personal, philosophical and conscientious beliefs.”
According to Peterson, it took a few years before pro-vaccine bills were introduced that would tighten existing nonmedical exemptions.
“Washington state was probably the first state that had an educational requirement for parents seeking a personal belief exemption,” she said. “Rather than only having to check a box on a form and send the form back to the school or day care, parents have to physically go into a physician’s office or other health care provider and receive information about the risks and benefits of the vaccines, and the diseases and the consequences of the decision they were about to make.”
Both Oregon and California followed suit, passing bills that added the educational component to the process, with other states continuing to follow.
“Other bills that I have seen are adding more administrative requirements to the process,” Peterson said. “The overall belief is that it should not be easier to get children into school without vaccinations than it is to get them into the school with vaccinations.”
AMA takes a stance
The American Medical Association recently took a stance on tighter limitations on vaccination opt-outs, with the goal of minimizing the susceptibility of the overall population to vaccine-preventable diseases.
According to an AMA press release, the new policy enacted by the association addresses the re-emergence of vaccine preventable diseases in the U.S. and requires states to move toward banning nonmedical vaccination exemptions. With this new policy, the AMA stated it will seek more stringent state requirements to allow vaccination exemptions for medical reasons only.
“The Pediatric Infectious Diseases Society completely agrees with the AMA’s stance,” Kimberlin, who is the society’s immediate past president, said. “Every major medical organization that I know of supports these types of restrictions, and the reason is that we have known in the medical field for years what will happen without vaccinations. The entire country saw what will happen without them with the Disneyland outbreak. It is not rocket science, it is pathetically predictable. You decrease vaccination rates, and the disease roars back. The good news is that resurgences like this can be stopped and then prevented with a renewed commitment to vaccination programs.”
“People need to do the right thing. We are all connected to one another. We live in communities and with this comes responsibility. Vaccinations not only protect one’s own child, they protect all children. The current movement across the country that was most visibly highlighted by the California law just passed is unequivocally a move in the right direction.”
Orenstein said a major goal of these laws and limitations is to protect those who are unable to be vaccinated because they are too young or have medical contraindications.
“When someone is vaccinated, they are not only getting protection for themselves, but they are getting protection for their communities,” Orenstein said. “The rationale and the requirements are based` not only upon individual protection, but community protection. And specifically, community protection for people who cannot be vaccinated. They are protected if they are not exposed, and the likelihood of them being exposed is very slim if everybody else who can be vaccinated in the community is vaccinated.”
The role of pediatricians
The pediatrician, as always, remains the front-line person to address parental vaccine safety concerns and vaccine refusals in this latest trend in vaccination avoidance, Romero said.
“As an infectious disease specialist, I have more time than a pediatrician to spend with parents when seeing a child in the clinic. Sitting down and talking with a parent is certainly the way to do this, but I realize that the pediatrician may not have the time to spend 20 or 30 minutes discussing vaccines with a parent,” he said. “Providing parents with literature or sending the parents to the websites or blogs where they can obtain accurate information on vaccinations is helpful. We should offer ‘firm’ recommendations for childhood vaccinations. Pediatricians can have the nurses in their practice provide immunization information to the parents and discuss it with them. Organizations, such as the American Academy of Pediatrics, should continue to provide information and educate parents about the benefit of immunizations that vaccines save lives and that they are safe.”
Regarding ways to manage and increase timely vaccination among patients, Allison Kempe, MD, MPH, of Children’s Outcomes Research at the Children’s Hospital Colorado, and colleagues conducted a study to assess physician responses and attitudes toward parental requests to spread out the recommended vaccination schedule among children aged younger than 2 years. They also assessed the strategies used and perceived effectiveness in response to these requests.
According to the results published in Pediatrics, the researchers found that “virtually all providers encounter requests to spread out vaccines in a typical month and, despite concerns, most are agreeing to do so. Providers are using many strategies in response but think few are effective. Evidence-based interventions to increase timely immunization are needed to guide primary care and public health practice.”
“Parents come to the pediatrician’s office asking for deviations from the recommended vaccination schedule and pediatricians may modify,” Romero said. “They do not give the vaccines when they are supposed to be given. In doing so, they are not providing the maximum protection afforded by the vaccines.”
Practicing at Children’s Hospital of Alabama, Kimberlin said the pediatrician’s office is impacted every day by this, even before the Disneyland outbreak and before these legislative efforts arose.
“This is an everyday conversation that pediatricians have across the country. I do not think these laws will increase such conversations because they are already occurring with incredible frequency, and it takes a tremendous amount of time to convey information to parents,” he said. “It is a real challenge, because there are many patients to be seen throughout the day, and there simply is not time to take one and a half hours out to talk through this because other children need to be seen as well.
“I personally think that these laws that are being passed or [that] are under consideration strengthen the hand of the pediatrician because it shows that societally, we as a country and community, have considered the risks and benefits and have come down strongly in favor of vaccines and vaccinations. It helps remove the perception of gray areas and decrease confusion. Vaccines save lives and that is the only answer here.” – by David Costill and Jennifer R. Southall
- References:
- Jain A, et al. JAMA. 2015;doi:10.1001/jama.2015.3077.
- Kempe A, et al. Pediatrics. 2015;doi:10.1542/peds.2014-3474.
- Zipprich J, et al. MMWR. 2015;64:153-154.
- www.ama-assn.org/ama/pub/news/news/2015/2015-06-08-tighter-limitations-immunization-opt-outs.page. Accessed July 20, 2015.
- For more information:
- Andy Baker-White, JD, MPH, can be reached at the Michigan Public Health Training Center, The University of Michigan, 1415 Washington Heights, Room 2700, Ann Arbor, MI 48109-2029; email: abakerwhite@networkforphl.org.
- Aaron E. Glatt, MD, can be reached at South Nassau Communities Hospital, One Healthy Way, Oceanside, NY 11572, email: aaron.glattmd@snch.org.
- David W. Kimberlin, MD, can be reached at the University of Alabama at Birmingham, 1720 2nd Ave South, Birmingham, AL 35294; email: DKimberlin@peds.uab.edu.
- Walter A. Orenstein, MD, can be reached at Emory University School of Medicine, 201 Dowman Drive, Atlanta, GA 30322; email: worenst@emory.edu.
- Diane C. Peterson, can be reached at the Immunization Action Coalition, 2550 University Ave. West, Suite 415 North, Saint Paul, MN 55114; email: diane@immunize.org.
- José R. Romero, MD, can be reached at Arkansas Children’s Hospital, 1 Children’s Way, Little Rock, AR 72202; email: RomeroJose@uams.edu.
- Robert Schechter, MD, can be reached at the California Department of Public Health Immunization Branch, PO Box 997377, MS 0500, Sacramento, CA 95899-7377; email: Carlos.Villatoro@cdph.ca.gov.
Disclosure: Baker-White, Glatt, Kimberlin, Orenstein, Peterson, Romero and Schechter report no relevant financial disclosures.