You are a member of the Hepatitis Unit of the Centers for Disease Control and Prevention in Atlanta, Georgia. The year is 1968. On May 15th, a request to assist in the investigation of an outbreak of infectious Hepatitis A was extended. You learned that 55 cases of infectious hepatitis had been reported to District #2 Health Department in North Trail, Michigan.

Knowing that between April 1 and May 15, 1968, there were 55 cases of Hepatitis A infection reported to the County Health Department, could you conclude that this is a problem of epidemic proportion?

Are 55 cases in excess of normal expectancy?
How did you establish whether this is greater than expected?

As members of the Hepatitis Unit you determined that all of the reported hepatitis victims should be interviewed as the first step of the investigation. They will be interviewed in their homes if possible. What questions will you ask?You should identify at least ten questions.

What other actions might you take at this time in the investigation while you are at the victims’ homes?

What information can you identify from studying daily incidence and the epidemic curve?

Make observations about the characteristics of the outbreak in terms of time (i.e, Which decade of age had the highest attack rate? And What hypothesis relative to time and person can you make at this point in the investigation?)

Sample Solution