1. An Analysis in Measles Outbreak of
2014: The Role of Personal Beliefs
Exemptions.
FELIX SHIH
GEOGRAPHY490
CALIFORNIA STATE UNIVERSITY, NORTHRIDGE
DEPARTMENT OF GEOGRAPHY

2. Measles, Mumps, and Rubella (MMR)
vaccination.
 A viral infection that's serious for children, it is one of the leading
causes of death among young children. Before the introduction of
the vaccination in 1980s, measles caused an estimated 2.6 million
deaths each year.
 the modern vaccination of Measles, Mumps, and Rubella (MMR)
vaccination has two doses of vaccine recommended for children:
the first dose is administered at 12-15 months of age and the second
dose at 4-6 years of age.
 The measles component in the MMR vaccine has been in use since
1968. The vaccine is so effective that the United States eliminated
measles in 2000.

3.  In general, the safety record of the MMR vaccine is good. Most
children who get the vaccine do not have any side effects. So far
the MMR vaccine has been linked with a very small risk of seizures
that lead to a fever and this risk increases as infants get older. Other
risks with the vaccine that include joint pain, temporary arthritis, and
a disorder that decreases the blood platelet count are rarer.

4. Andrew Wakefield
 The safety of the vaccine only became a controversy
after Andrew Wakefield’s paper was published in 1998.
 The paper showed a false link to autism from the MMR
vaccine by using only 12 cases as evidence.
 This flawed information was distributed widely by non-
scientific journalism and mass media. As the result,
many parents still do not believe the vaccine is safe
even it has been further tested for safety.

5. Religious and Personal Belief
Exemptions
 Religious and personal belief exemptions
for vaccination are allowed in all states
in the U.S. except Mississippi and West
Virginia.
 California does not clearly recognize
religion as a reason for claiming an
exemption, however, the non-medical
exemption in the state of California has
Philosophical (Personal) Exemption can
be use, so the reason of use exemption
can be both religious and personal
belief.

6. Research Question
 This research proposes to examine vaccination and immunization
rates according to different factors:
 Ethnicity (Caucasians or Hispanics)
 Median household income (High - Low)
 Personal belief rate (High - Low)
 Religious belief rate*
*Since there has no data for religious belief rate, I use the number of churches instead.

7. Study Area
 Los Angeles County, with an
approximate population of
ten thousands (Estimate in
2014: 10,116,705). There are
1672 kindergartens located
within in Los Angeles County.

10. Data
 On September 3, 2014, The Los Angeles Times released a list of
thousands of kindergartens within the county containing each
schools’ MMR vaccination rate and exemption rates. Original data
is from California Department of Public Health
 Number of population with ethnicity data and median household
income in census 2013 data from U.S. Census Bureau.
 Distribution of churches in Los Angeles County is provided by the
USA churches from ArcGIS online.

11. Method and Analysis
 ArcGIS to make spatial join and selection:
 Join churches with census tracts.
 Select the tracts that contains kindergartens
 Statistical analysis tool on Microsoft Excel
 Due the skewness exists on all data, conversion is needed.

12. Analysis: Correlation

13. Analysis: Correlation (cont.)
 Personal believe rate (2014) :
 positive correlation with personal belief exemptions, Caucasian
population, age and income
 negative correlation with MMR vaccination rate and immunization rate
 Hispanic population has quite strong positive correlation with
vaccination rate.
 Churches have very weak correlation with all variables except
density of population.

14. Analysis: Regression
This regression
analysis used 2014
personal belief
rates as a
dependent
variable.
32.4% of the variation in
personal belief rates can be
explained by the
independent variables in
table.
The significance F is far less
than 0.05, H0 is rejected at
significance level 0.05 so
this regression is statistically
significant.

15. Analysis: Regression cont.
 Significance P-values in four independent variables; 2013 personal belief
exemption rate, 2013 MMR vaccination rate, Caucasians and Hispanics are far
lower than 0.05 significant level.
 For every percentage of increased in the Caucasian population, their personal belief
rates are increase by about 76%.
 For every percentage increase in the Hispanic population, personal belief rates are
decreased about 53.3.
 For each percentage of vaccination rate increase, about 9% decrease in personal
belief rate.
 17.1% increase in personal belief rate for each percentage of median household
income
 Immunization and number of churches have p-value higher than 0.05 significance level
so the relationship with personal belief rate are not clear.

16. Conclusion
 This model has good explanation for the relationship between
personal belief / exemption, vaccination and ethnicity population,
however, the impact on the measles immunization is unclear.
 Personal belief exemptions are very likely used by Caucasians
 People with high median income in population is likely to use
personal belief exemptions.
 Hispanics and low income are unlikely to use personal belief
exemptions, so they are likely to be vaccinated.

17. ACKNOWLEGEMENTS
 Professor Julie Laity for research essay guidance
 Professor Steven M. Graves for statistical analysis
 Los Angeles Times for data (Plunge in kindergartners' vaccination
rate worries health officials, September 3, 2014)