This qualitative assessment provides an enhanced understanding and appreciation of the perspective, practices and challenges that staff of CCCs experience in responding to enteric illness and outbreaks. In general, it was found that CCC staff are dedicated to and well informed about the children they work with and have a tremendous responsibility. Results from this study will be useful to public health officials responsible for developing tools and resources to further support or better inform current knowledge and practices for preventing and managing enteric disease. The recommendations from this study were made based on data directly from staff of CCCs and are designed to be practical and developed in further collaboration with them. The experience and knowledge CCC staff use to identify and take action for prevention and management of enteric illness clearly demonstrates their responsibility as gatekeepers of health among the children they care for. Dating the time of viral subtype divergence Precise dating of viral subtype divergence enables researchers to correlate divergence with geographic and demographic occurrences. When historical data are absent (that is, the overwhelming majority), viral sequence sampling on a time scale commensurate with the rate of substitution permits the inference of the times of subtype divergence. Currently, researchers use two strategies to approach this task, both requiring strong conditions on the molecular clock assumption of substitution rate. As the underlying structure of the substitution rate process at the time of subtype divergence is not understood and likely highly variable, we present a simple method that estimates rates of substitution, and from there, times of divergence, without use of an assumed molecular clock. We accomplish this by blending estimates of the substitution rate for triplets of dated sequences where each sequence draws from a distinct viral subtype, providing a zeroth-order approximation for the rate between subtypes. As an example, we calculate the time of divergence for three genes among influenza subtypes A-H3N2 and B using subtype C as an outgroup. We show a time of divergence approximately 100 years ago, substantially more recent than previous estimates which range from 250 to 3800 years ago. Precise estimates are sorely lacking for dating the emergence and divergence of viral subtypes. Improved estimates equip epidemiologists and virologists to begin to correlate these important establishing events with historical demographic changes, geographical invasions and zoonoses, the transferring of a virus from one host species to another [7, 1, 25] . For example, archeological sequence data can furnish accurate dates and show that substantial genomic changes associate with geographical invasion and zoonosis [14, 17] . Further, the recent availability of viral gene sequences sampled at a pace commensurate with their rate of nucleotide substitution vastly augments the ability to rigorously infer the time scale of phylogenies and hence determine the time of the most recent common ancestor (TMRCA) for different viral types [18, 26, 6] .