Question 1
Researchers have proposed that the herpes virus responsible for the childhood illness roseola may cause a type of T cell leukemia. Ninety percent of the population has been infected by the virus by two years of age, but the T cell leukemia is relatively rare. The virus can be cultured in the laboratory in tissue culture, but not in mature organisms. Discuss the obstacles to applying Koch's postulates to the etiology of this disease.
Question 2
Describe three types of reservoirs of infectious disease in humans. Give an example disease for each type of reservoir.