This case study is designed to raise awareness of the use of high-throughput screening (HTS), the resources available at PubChem, and the potential for discovery of promising therapeutics in collections of existing drugs. Students prepare for the case by viewing several background videos. Once in class, they access a published and highly cited HTS screen for small molecules to stop Zika virus epidemics, and then interact directly with the data in PubChem to dissect the research findings. The case can be extended to consider how similar approaches and PubChem database searches can be used in the search for drugs to combat the novel coronavirus responsible for the COVID-19 pandemic. The case is ideally suited for upper-division undergraduate students or graduate students (e.g., first year or professional students in pharmacy or medicine) in a molecular biology or medicinal chemistry course with enough time for class work in groups and productive discussions.