On Christmas Eve of 1998, the Ohio State Health Department announced that two elderly people had died during the previous six weeks, apparently after ingesting tainted meat. Ten additional non fatal cases were reported in the state during this period. The state epidemiologist was aware of a national outbreak of a disease with the symptoms seen in these cases. The symptoms included fever and muscle aches, and often diarrhea and nausea. Occasionally, the central nervous system was affected, resulting in confusion, stiff neck, headache, and convulsion. The nationwide outbreak affected approximately 50 people, with a particularly high infection rate in pregnant women and a significant number of deaths among fetuses. The Centers for Disease Control and Prevention (CDC) issued a list of people who were at particular risk for the disease. These included pregnant women, newborns, people with weakened immune systems, and the elderly. The CDC and the U. S. Department of Agriculture suspected pre packaged meats, such as hot dogs and cold cuts, as the source of the outbreak. Required:
a. What is the most likely cause of the disease?
b. Why is this infection associated with processed meats, but not usually with hamburger or cuts of meat including pork, beef, or chicken?