Dr. Laura Pulscher has a wealth of experience when it comes to identifying viruses in her samples. Her One Health education has taken her from the United States to India, Australia, Christmas Island, and back again, providing a unique skillset to analyze
infectious diseases from humans, animals, and the environment. But when faced with 500 samples from poultry, humans, and their shared environment collected from Vietnamese live bird markets, she raised a concern: How should one prioritize which influenza
strains to test for, and in which samples?
In her paper, which was just published in the journal Influenza and Other Respiratory Viruses, Dr. Pulscher focused on making influenza A virus characterizations
more efficient by capitalizing on what we know about the different virus species’ endemicity in specific human and animal hosts. Her algorithm divides sample types into avian, swine, human samples and all other animals. She studied the literature
and consulted with experts to design a specimen flow algorithm that is both more efficient and more economic for researchers to follow. It also helps researchers to identify influenza A viruses which may have jumped species and may be more prone to
cause epidemics in the new host.
Influenza A species are determined by their hemagglutinin (HA) and neuraminidase (NA) subtypes. For example, the species most relevant to humans include seasonal H3N2 and H1N1. In swine, we are more concerned with H1N1, H1N2, and H3N2 subtypes. For birds,
we are particularly concerned with detecting H5 and H7 subtypes which can cause severe epidemics and death in animals. We also frequently look for the less dangerous H9 virus strains. With Dr. Pulscher’s algorithm, it becomes easier to
prioritize which subtypes to test for when one is faced with the possibility of having many unique influenza A virus types in a group of samples but have limited time or money to study them. Her paper is likely to help laboratorians in developing
countries with limited access to tools such as Next Generation Sequencing.
In the UTMB One Health Laboratory, Dr. Pulscher and others have several ongoing research projects in which influenza A testing is used. The aforementioned flu surveillance on Vietnamese bird markets, of course, is one of them. The lab team is currently also studying samples from the human-animal
interface in Mexico, Pakistan, the Philippines, and the United States. They will continue to test human samples for influenza A when there is suspicion that a novel influenza is present or that a zoonotic influenza virus has spilled over to a new
species. Influenza remains a threat to populations globally given its potential to jump between species, and proactive One Health surveillance seeks to prevent such catastrophes.
Reference:
- Pulscher, L. A., Webby, R. J., & Gray, G. C. (2024). An algorithm for the characterization of influenza A viruses from various host species and environments. Influenza and Other Respiratory Viruses, 18(2), e13258. https://doi.org/10.1111/irv.13258