RAPID: Measuring host competence across wild bird species during outbreaks of highly pathogenic avian influenza

University Of Massachusetts Boston, Dorchester MA

Investigators

Abstract

This RAPID will study the current outbreak of highly pathogenic avian influenza (HPAI) in North American birds, focusing on host competence as a way to estimate which species are primary reservoirs and sources. The spread of HPAI in North America in the past year poses catastrophic consequences for the health of wild birds and poultry. The virus can readily jump the species barrier leading to concerns that continued spread of HPAI in animals could start a pandemic in humans. The scale of the current North American outbreak is unprecedented both in terms of the number of infected birds, and the geographic area impacted. This strain of HPAI is a multi-host pathogen that within North America is demonstrating transmission back and forth between wild birds and poultry. The spread of HPAI in the U.S. has involved a wider diversity of birds than previously observed - well beyond the traditional poultry reservoir. There are over 1,000 wild bird species in the U.S. and over 100 species have become infected with HPAI in the last 6 months. Depending on the wild bird species, HPAI can cause disease ranging from mild to severe, or in extreme cases death. A rapid response to the outbreaks is crucial to identify how wild birds are contributing to transmission in the U.S. with the goal of developing models to predict the risk of the virus jumping to novel hosts. Currently there are challenges with predicting how wild birds will influence HPAI transmission due to a lack of information about their host competence, defined as the ability of an individual to become infected and cause infection in other hosts. Characterizing host competence requires a systems approach to unify host traits (disease severity, body condition) and pathogen traits (replication dynamics, pathogen viability). This study will capitalize on an extensive and well-developed network of collaborations with wildlife managers and rehabilitation clinics to ensure sampling of a wide diversity of birds in the North Atlantic, a region that has emerged as a geographic hotspot for HPAI. This study will characterize the range of host competence of wild birds and will integrate ecological and life-history traits of wild birds into models of disease prediction by testing whether aquatic foraging and predation on aquatic species are linked to transmission. Information gained will be critical to develop a mechanistic understanding of HPAI dynamics, allowing for more informed decision-making about animal and human health as the outbreak unfolds. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.