What is the fine-grained topic of the following text: "If we could discover the sources of this strain, the transmission pathways that allow it to spread so effectively, and the factors that have led to its rapid emergence, we could find ways to intervene and possibly slow or halt this strains emergence," says study author James Johnson, MD, of the VA Medical Center in Minneapolis. Only return the topic.
Study on the sources, transmission, and rapid emergence of a disease strain