Ayanna Johnson, a student from Norfolk State University, worked with Dr. Andrew Park on transmission of viruses from birds to horses.
Abstract: The spread of influenza from wild birds to horses impacts the livelihood of people in Mongolia, where horses play an important role in their livelihood. Additionally, such cross-species transmission could potentially lead to a pandemic. This project underscores how seasonal transmission dynamics and the risk of pathogen introduction influences the spread of influenza. Seasonality transmission includes the behavior of the horses, environmental persistence of the flu, migration, and also the different positivity rates of the horses. Samples from various horse herds have been obtained through multiple trips in Mongolia at three different points of time. To visualize this data, the information was transformed into various maps and graphs using the ggplot package in R. We developed a stochastic SIR model to simulate exposure to, and transmission of, influenza. By varying pathogen exposure risk, amplitude of seasonality, and baseline environmental transmission in combination with literature estimates of other parameters, we established the conditions likely involved in bird-to-horse influenza transmission in Mongolia. An important additional finding is that seasonal exposure can mask the identification of high versus low risk exposure groups; rates of waning immunity and seasonal transmission interact so that differences in positivity rates are only apparent between groups at certain times of year.
Johnson_poster