QUESTION 1 Recently, a report was published describing a string of cases of Norwalk virus gastroenteritis...
QUESTION 1 Recently, a report was published describing a string of cases of Norwalk virus gastroenteritis among passengers on cruise ships. From this report, an epidemiologist went on to form a number of hypotheses as to why there had been this rather unusual increase in reported gastroenteritis outbreaks on cruise ships in 2015. The cruise ship owners contacted the Centers of Disease control and Prevention (CDC) to conduct an in-depth analysis of the possible modes of transmission of the Norwalk virus in the cruise ship environment. CDC investigators interviewed all of the passengers on the last affected cruise (N=3,000) and obtained information on the passenger's recreational activities. They found the following results: 1,000 passengers had gone swimming in the upper deck pool and 2,000 passengers had never gone swimming in the upper deck pool. One hundred (100) of the passengers who swam in the upper deck pool and 100 of the passengers who did not swim in this pool developed Norwalk virus gastroenteritis during the cruise. FYI: The cruise lasted one week. a)Set up the 2x2 table for this data. (b) Calculate the risk ratio of gastroenteritis associated with swimming in the upper deck pool N.b. There are three parts to the answer here. The first two are elements of the risk ratio. The third is the risk ratio itself. Format: (x)/(y) = (2) Hints: X & Y should be fractions, Z is not. X refers to Step 1, Y refers to Step 2, Z refers to the RR/= 5 points c) State in words your interpretation of the above risk ratio.