Dr. Nelli is committed to advancing the understanding of viral pathogenesis and host immune responses while also developing innovative diagnostic tools to enhance disease control measures. His research program is centered on collaborative and independent studies focusing on influenza A viruses, specifically on receptor distribution, coronaviruses in animal populations, and other pathogens of significant importance to livestock. Critical areas of investigation include the underlying risk factors for viral transmission at the animal-human interface, the evaluation of host susceptibility to these pathogens, and the analysis of factors contributing to pathogenesis, all of which are vital for effective disease prevention and outbreak containment. His laboratory has pioneered the development of 3D cell cultures, known as "mini-tracheas" or "mini-guts," in various animal species, including humans, pigs, cattle, horses, cats, dogs, deer, elk, and bats.
Dr. Nelli’s diagnostic research directly benefits the National Animal Health Laboratory Network (NAHLN) laboratories across the United States, as well as various stakeholders, including the USDA-APHIS, the FDA (Veterinary Laboratory Investigation and Response Network), veterinarians, and diagnostic professionals globally. As a Principal Investigator (PI), he has secured over $1.9 million in extramural funding to support his research endeavors and has published > 40 manuscripts.