Professionalism/The Disneyland Measles Outbreak of 2014-2015

The OutbreakEdit

Measles is a viral infection that is serious for small children and causes a rash and fever and is preventable by vaccine. The virus infects mucus in the nose and throat and can live for up to two hours in the airspace where an infected person has coughed or sneezed, making it extremely contagious. Furthermore, an infected person can spread the disease up to four days before they have a visible rash [1]. Before the invention of the measles vaccine, between 3 and 4 million people in the U.S. were infected annually. The vaccine became available in 1963 and by 2000, the Center for Disease Control and Prevention (CDC) declared measles eliminated from the U.S. Elimination is defined as the absence of continuous disease transmission for greater than 12 months [2].

Figure 1. Number of confirmed measles cases (N = 110),* by date of rash onset — California, December 2014–February 2015 [3]

On January 5, 2015, the California Department of Public Health was notified of a measles case: an 11 year old boy who had recently visited Disneyland in Orange County, California. Five other cases were reported that day and all of the patients had visited the Disney park within the period of December 17-20, 2014. By January 7, 2015, 7 measles cases were confirmed by the California Department of Public Health. By February 11, 125 measles cases were confirmed in the period of December 28, 2014 - February 8, 2015. 111 of these cases were in the state of California. Figure 1 shows the timeline of measles cases reported. The patients ranged in age from 6 weeks old to 70 years old with a median age of 22 [3]. The outbreak was officially declared over on April 15, 2015 [4].

Out of the measles patients from December 29, 2014 to February 8, 2015, 36% were infected at the Disney parks in Orange County, California and 31% were a secondary infection (receiving the virus from someone who had visited the parks). The remaining patients’ source of infection is unknown [3].

The outbreak was caused by inadequate levels of vaccination. Among the patients in California, 45% were unvaccinated. Only 12% were reported to be vaccinated and the rest had an unknown vaccination status. Of those who were vaccine-eligible, 67% were intentionally unvaccinated for “personal beliefs”. The measles vaccine (administered as a combination vaccine against measles, mumps and rubella) is typically done in two doses, one at one year old and one at four years old [3]. Because measles is highly contagious, vaccination rates of 96%-99% are necessary to prevent outbreaks [5].

While parents may choose to exempt their children from the vaccine altogether, they may also delay their child’s vaccination or not continue with the second dose. Low vaccination rates, combined with the large number of international visitors, made the Disney parks highly susceptible to this outbreak. Although the initial source of the virus is unknown, the strain was the same genotype that caused a previous outbreak in the Philippines [3].

Response to the Measles OutbreakEdit

As a result of the measles outbreak in 2015, both Disney and the California Department of Public Health (CDPH) responded to the situation in ways that best suited their organization’s needs and objectives. The CDPH responded proactively while Disney adopted a low profile, but gave full support and compliance to the decisions of the CDPH. Though their responses were considerably different, both strategies were successful [6].

Disney’s ResponseEdit

Disney’s response strategy was to align authority of managing the outbreak with the state public health department. Disney conveyed its support for the medical community’s management through media interviews and statements. Disney’s chief medical officer, Dr. Pamela Hymel, said, “we are working with the health department to provide any information and assistance we can,” [6].

Disney also revealed that the outbreak had affected its employees, and the company was taking precautions to reduce spreading the disease. The company said, “we immediately began to communicate to our cast [employees] to raise awareness,” and “in an abundance of caution, we also offered vaccinations and immunity tests. To date, a few Cast Members [employees] have tested positive and some have been medically cleared and returned to work. Cast Members who may have come in contact with those who were positive are being tested for the virus. While awaiting results, they have been put on paid leave until medically cleared,” [6].

By positioning itself as not centrally involved but cooperative with health officials, Disney was relatively unaffected by the crisis. Park attendance during and after the measles outbreak remained high and the company even increased ticket prices while the numbers of people infected with measles continued to increase [6].

The CDPH’s ResponseEdit

The CDPH took a more proactive, involved approach to addressing this issue. They responded in two key ways. The first, was to provide frequent updates about the spread of the disease, the numbers of people affected, and whether those people were immunized. These updates highlighted the spread of the disease across the US and the importance of immunization as the best protection against measles. This strategy of providing constant updates on the numbers of infected due to not being vaccinated served as a reminder of the need for immunization. It also debunked anti-vaccine claims on social media, as social media comments on #disneymeasles by anti-vaccine supporters were debunked by vaccine advocates who used the outbreak as evidence [6].

The second main response by the CDPH was to sign a legislative bill into law on June 25, 2015 that substantially narrowed acceptable exceptions to school-entry vaccinations. This law disallowed exemptions for religious and philosophical beliefs, only permitting medical exemptions [6]. This bill, Senate Bill 277, requires students entering kindergarten and seventh grade in the state of California to be fully vaccinated. During the following year, the number of vaccinated kindergarteners increased by three percent and non-medical exemption rates dropped to the lowest figure in over a decade [7].

Vaccination DebateEdit

Since the measles outbreak, the vaccination debate has renewed [1]. Government authorities have long championed for vaccination. The United States federal government does not have an overarching vaccination law, but all 50 states have vaccination requirements to attend public schools. When the CDC declared measles eradicated, some states loosened their vaccination requirements and broadened exemption. However, recent outbreaks have caused mandated vaccinations.

Jacob v. Massachusetts 1905 settled mandatory vaccination for the first time. Despite weaker scientific evidence for vaccines and lacking legal precedence, the Supreme Court ruled "...shall be governed by certain laws for the ‘common good,’ and that government is instituted ‘for the protection, safety, prosperity and happiness of the people, and not for the profit, honor or private interests of any one man..." and established four standards for vaccination: necessity, reasonable means, proportionality, and harm avoidance.[2]

Government Renews EffortEdit

Officials have credited the lack of vaccination as the cause of the recent measles outbreak. A UNICEF report found that 2.593 million children missed their first measles vaccine dosage in the United States from 2010 to 2017 [3]. France is second with 608,000. Second dosage misses are higher. Henrietta Fore, UNICEF Executive Director, said, “The ground for the global measles outbreaks we are witnessing today was laid years ago. The measles virus will always find unvaccinated children… we need to vaccinate every child, in rich and poor countries alike.” The CDC reported over 1,000 measles cases in over 20 states from end of 2018 through April 26, 2019 [4]. In 2017, there were only 75 cases. The other spike occurred in 2014 during the Disneyland outbreak. They cite two main causes, unvaccinated U.S. travelers contract measles abroad and bringing it back into the U.S. and further spread of measles in U.S. communities with pockets of unvaccinated people. States including New York and California have introduced stricter vaccination requirements [5]. These requirements denied all vaccination exemptions except medical conditions proven by a physician. Anti-vaxxers have challenged these sweeping changes citing risk and constitutional freedom.


Anti-vaxxers oppose mandated vaccination citing rights and freedom [6]. California state bill SB277 required virtually all public and private school students to be vaccinated against contagious illnesses, prompted by the Disney outbreak. The bill only exempted medical conditions and home schooled students. However, opponents challenged the bill in court [7]. The Second District Court of Appeal ruled that the bill did not deny students’ right to an education since “Compulsory immunization has long been recognized as the gold standard for preventing the spread of contagious diseases”. They used a 1944 Supreme Court child-labor law ruling as precedence to address freedom of religion, “The right to practice religion freely does not include the liberty to expose the community or the child to communicable disease or the latter to ill health or death.” State Sen. Richard Pan, D-Sacramento praised the court for “rejecting unproven assertions and accepting the scientific evidence” when it shot down other arguments, such as “our constitutional right to live vaccine-free,” “medical experiment,” and “totalitarian mandate.”

Recent measles outbreak in New York also sparked litigations [8]. Parents successfully appealed a New York county’s ban of unvaccinated children from schools and parks, punishable with jail time and a $500 fine. Judge Thorsen agreed that the ban “denied attendance at nursery programs and schools and has effectively prohibited their movement and denied them the right to congregate and assemble in public places.” Extremist even compared the measure to Nazi persecution of Jews since measles hit Orthodox Jewish communities the hardest. The county does not plan to contest the ruling since the goal was to promote vaccination. They did not even plan on arresting violators.

Conclusions about Professional EthicsEdit

Research shows distrust in vaccines and government readiness. A Zogby Analytics and Research!America study found that 46 percent of participants believed infectious and emerging diseases will pose a major threat in the next few years. However, only 14 percent were very confident in the government to prevent such a threat, and only 32 percent were confident in the government's regulation and recommendation of vaccines [9].

A National Institute of Health study on public trust in vaccination concluded that “...neglect or abuse from a government or health system was often seen as an underlying reason for distrust in vaccines among marginalized groups...” and identified 3 areas of trust, product, provider, and policy-makers [10]. Effective prevention requires inoculating a large proportion of the population. To do so, society needs to consider external influences, such as religion and ethnicity, and continuously work to build a generalized trust.


  1. "The anti-vaccination movement". Measles and Rubella Initiative (American Red Cross). 2019. Retrieved 2019-05-06. 
  2. Gostin, Lawrence (2005-04). "Jacobson v Massachusetts at 100 Years: Police Power and Civil Liberties in Tension". US National Library of Medicine (National Institute of Health). Archived from the original. Error: If you specify |archiveurl=, you must also specify |archivedate=. Retrieved 2019-05-06. 
  3. "Over 20 million children worldwide missed out on measles vaccine annually in past 8 years, creating a pathway to current global outbreaks". UNICEF (United Kingdom: Unicef UK). 2019-04-25. Retrieved 2019-05-06. 
  4. "Measles Cases and Outbreaks". CDC (Atlanta: CDC). 2019-05-03. Retrieved 2019-05-06. 
  5. Egelko, Bob (2018-07-03). "California’s mandatory-vaccination law survives court test". San Fancisco Chronicle (Hearst). Retrieved 2019-05-06. 
  6. "Zero Tolerance Vaccine Laws in America: Will You Defend Vaccine Freedom?". National Vaccine Information Center (Sterling, VA). 2018-07-01. Retrieved 2019-05-06. 
  7. Egelko, Bob (2018-07-03). "California’s mandatory-vaccination law survives court test". San Fancisco Chronicle (Hearst). Retrieved 2019-05-06. 
  8. Sellers, Frances; Fisher, Barbara (2019-04-06). "Judge rules New York county can't ban unvaccinated children from schools, parks". Washington Post. Archived from the original. Error: If you specify |archiveurl=, you must also specify |archivedate=. Retrieved 2019-05-06. 
  9. "Americans’ Views on Vaccines and Infectious Disease Outbreaks" (pdf). Zogby Analytics (Arlington: Research!America). 2018-05-01. Retrieved 2019-05-06. 
  10. Larson, Heidi (2018-05-10). "Measuring trust in vaccination: A systematic review". US National Library of Medicine (National Institute of Health). Archived from the original. Error: If you specify |archiveurl=, you must also specify |archivedate=. Retrieved 2019-05-06.