Assignment:
On 6/20/2019 student 13 arrived at the ER with fever, minor jaundice, headache, and abdominal pain. Shortly after, several other individuals from the same educational institution were attended at other ER facilities, and clinics with similar signs and symptoms. Upon testing, it was determined the students had contracted hepatitis B. Health authorities were informed. Theoutbreak appearedamong a group of students who met two months earlier for a weekend of wild partying. Hepatitis B, a disease transmitted by body fluids, is characterized by jaundice, weakness, abdominal pain, nausea, and fever. The County Health Department, and the local health facilities have stepped in to identify the possible source of the infection.The identification of the source of the outbreak is needed to prevent further spread.
1. Mention two behaviors that could lead to the spread of hepatitis B.
2. Contrast the mode of transmission of hepatitis B with those of COVID 19 virus (SARS COV 2 virus).
3. Why is an epidemic of hepatitis B unlikely?
After extensive questioning of all the students involved, the following close contact incidents have been stablished between the exposed population. Each student has been assigned a number. The two numbers in the boxes showed the two students who had close contact. The order of the boxes recreates the sequential order of the close contact events that occurred within the two days of exposure.
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Contact sequence
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1st
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2nd
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3rd
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4th
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5th
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6th
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7th
|
8th
|
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Students who had close contact
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3 <-> 11
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15 <-> 4
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7 <-> 3
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8 <-> 3
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2 <-> 6
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4 <->3
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11 <-> 12
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10 <-> 15
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Contact sequence
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9th
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10th
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11th
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12th
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13th
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14th
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15th
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Students who had close contact
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5<->1
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9 <->8
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13 <-> 8
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14 <->7
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2 <-> 15
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13 <-> 12
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10<-> 7
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Here is a list of the students who were infected, as evidenced by antigen and antibody testing.
3, 4, 7, 8, 9, 10, 13, 14, 12
Here is the list of uninfected students as evidenced by antigen and antibody testing.
1,2,5,6,11,15
4. Which student appears to be the source of the outbreak?
5. Which student was the index case? What is the index case of an outbrake or epidemic?
6. Create aflow chart that plots the spread of the outbreak, starting at the source. Account for each of the infected students, and when/by whom they were infected.
7. What is the etiology of the outbreak?
8. What is the reservoir of the infectious agent causing the outbreak?
9. Define ‘incubation time". What is the incubation time for Hepatitis B in this outbreak?
10. Distinguish an outbreak from an epidemic.
11. What are some of the signs of hepatitis B?
What are some of the symptoms of hepatitis B?
12. Calculate the attack rate of the mock outbreak. Show your work.
Attack rate: # people infected / total # of people exposed x 100