Outbreak investigation

Question 1

What are the steps in an outbreak investigation?

Answer 1

1. listen to the person who picks you up from the airport
2. verify the presence of the outbreak
3. verify diagnosis
4. define and identify cases
5. describe outbreak in person, place, and time
6. develop hypotheses
7. design studies to conduct hypotheses
8. refine hypotheses and conduct additional studies
9. implement control and prevention activities
10. communicate findings

Question 2

What was the case definition of BPF?

Answer 2

acute illness in children 3 months to 10 years with fever of at least 101.3°F, abdominal pain/vomiting, petechiae/purpura within 72 hours of fever onset, and no evidence of meningitis, preceding conjunctivitis

Question 3

What was the hypothesis for BPF?

Answer 3

BPF was a bacterial infection and preceding conjunctivitis was a risk factor

Question 4

What initial study was conducted for BPF?

Answer 4

Case control by testing the eye samples that were associated with conjunctivitis among cases and controls

Question 5

What was a common between the cases but not associated with controls with BPF? Why was this result met with skepticism?

Answer 5

Haemophilus influenzae - it has previously been unknown to be associated with severe disease

CDC testing showed the strain to have virulent plasmids

Question 6

What was the intervention/control measures

Answer 6

developed a test for fast diagnosis

oral rifampin and topical chloramphenicol used to treat BPF during conjunctivitis stage