Case Study: Measles in Texarkana


Case Study: Measles in Texarkana
Read the following case study and answer all questions below in a Word document. You must submit your paper in proper APA format (see attached example –

note – an abstract is not required).
The following case study was taken from the CDC-EIS.
On Tuesday, November 3, 1970, the Center for Disease Control (CDC) in Atlanta received the weekly telegram of surveillance data from the Texas State Health

Department. The telegram reported 319 cases of measles in the state during the previous week. In contrast, Texas had reported an average of 26 cases per

week during the previous four weeks. In follow-up telephone calls, CDC learned from State health officials that 295 cases of measles had been diagnosed in

the city of Texarkana, including 25 in children reported to have been previously immunized.
An invitation to investigate the situation was extended to the CDC on November 4, 1970. An EIS officer departed for Texarkana early on November 5.
Texarkana is a city of roughly 50,000 that straddles the Texas-Arkansas state line. Texarkana, Texas (Bowie County), had a population of 29,393 in the 1960

census; the population had been stable during the 1960s. Texarkana, Arkansas (Miller County), had a 1960 population of 21,088.
Although Texarkana is divided by the state line, it is a single town economically and socially. Persons of all ages on both sides of town have frequent

contact. Churches, physicians, offices, movie theatres, and stores draw people from both the Arkansas and Texas sides of town. People cross the state line

to attend social functions such as football games and school dances. Many families have friends and relatives who visit back and forth on both sides of

town. Private nurseries and kindergartens receive children from both sides of town. The two sides of Texarkana, however, do have separate public school

systems and separate public health departments.
The Investigation
The investigators obtained names of cases from the health departments, physicians, school and nursery records. They conducted a door-to-door survey. They

also asked families of cases for names of other cases. They used the same methods of case-finding and epidemiologic investigation on both the Arkansas and

Texas sides of town.
Clinical Picture
The illness was clinically compatible with measles. Typically, the patients had a 4- to 5-day prodrome with high fever, coryza (runny nose), cough, and

conjunctivitis (red, irritated eyes) followed by the appearance of a bright maculopapular (red spots and areas) rash. The temperature usually returned to

normal 2 to 3 days after appearance of the rash, while the rash persisted for 5 to 7 days.
The Outbreak
Between June 1970 and January 1971, 633 cases of measles were reported from Texarkana. Dates of onset were accurately determined for 535 cases. Though

infants, adolescents, and adults were involved in the epidemic, the majority of cases occurred in children 1 to 9 years of age. Measles cases were not

evenly distributed within the two counties.
Measles in Previously Vaccinated Children
Before this outbreak, the proportion of children vaccinated against measles on the Arkansas side was substantially higher than the proportion vaccinated on

the Texas side. The Texas side had never had a community or school vaccination campaign for measles. In contrast, the Arkansas side had held mass community

programs against measles for school and pre-school children in 1968 and 1969.
Based on health department and physician records, investigators estimated that over 99% of children aged 1-9 years in Miller County, Arkansas had received

measles vaccine prior to the outbreak. The overall vaccination level in Bowie County, Texas, was estimated to be 57%.
In this outbreak, 27 of the measles cases in Bowie County and all 25 of the measles cases in Miller County gave a history of prior vaccination with live

attenuated measles-virus vaccine. Parental history of vaccination was corroborated for all the cases by clinic or physician records. Local health

authorities in both counties were very concerned that children who had previously received measles vaccine got the disease.
In previously vaccinated children aged 1-9 years in Bowie County, the measles attack rate in this outbreak was 4.2 per 1000; the comparable rate in

unvaccinated children was 96.9 per 1000. From these data, a vaccine efficacy of 95.7 percent was calculated. This is a minimum figure since it has been

assumed that all 27 children were correctly vaccinated and that all of the cases therefore represent vaccine failure.
In actuality. some of these patients did not receive vaccine under ideal conditions. Eight of the 27 previously vaccinated patients had been vaccinated by

nurses from the Texarkana/Bowie County Health Unit at a day nursery. The vaccine for these eight children had been carried back and forth to the nursery

from the Health Unit in a cooler in a car on three separate days in June and July 1970. Although a lapse in technique which allowed warming of the vaccine

cannot be documented here, it is a possible explanation.
An additional seven patients had been vaccinated under the age of 1 year. These children were vaccinated in the years 1963-67 when it was recommended that

measles vaccine be given at age 9 months. It has since been learned that a vaccine failure rate as high as 15% may accompany vaccination at 9 months in the

United States.

Answer the following questions (use appropriate APA headings instead of repeating the questions):
1. What would be the initial steps of your investigation into this outbreak, i.e., the steps before trying to find additional cases?
2. How might you look for additional cases?
3. How would you define a case for this investigation? Is it a sensitive, specific, or both case definition? Why would you use this type of case

definition (i.e. sensitive, specific, both)?
4. What interventions would you propose to stop the spread of infection?
5. What is the current recommendation by the CDC for measles vaccination in children in the U.S.? What is the current WHO recommendation for children in

developing countries? Discuss why there are differences and how this is relevant to the case study.
Please ensure you cite your references in APA format with a minimum of 3 references (You may use your textbook as a reference and you should have a minimum

of 3 academic outside references). Assignment will be graded based on the following areas: Foundation and synthesis of knowledge, application of knowledge

critical thinking, writing skills, and organization of ideas and format.