case 1 : Parents bring their 2-year-old infant into the emergency room of a clinic. The infant is suffering with diarrhea and vomiting, and initial observation shows a dangerous level of dehydration. Initial tests do not indicate a bacterial infection or the presence of bacterial toxins. Ruling out the involvement of a bacterial pathogen, discuss what other pathogens may be involved. Discuss the characteristics of these viruses and their associated diseases. case 2: Advances in genetic sequencing have revealed new information about virus mutation and gene transfer between host cell genomes and viral genomes. Why is this research important to public health?.