The purpose of this research is to leverage recently developed aerosol diagnostic and experimental methods to create an improved understanding of viral aerosol natural decay in poultry production…

The U.S. Department of Agriculture Animal and Plant Health Inspection Service awarded the Regents of the University of Michigan a cooperative agreement valued at $1.939 million on February 2, 2026, under the Plant and Animal Disease, Pest Control, and Animal Care program (CFDA 10.025).

The research examines viral aerosol natural decay and engineered air disinfection technologies in poultry production environments to mitigate airborne transmission of avian influenza. The University of Michigan will evaluate how elevated ammonia concentrations influence aerosol pH and the natural and engineered inactivation of viral aerosols through fundamental and applied experiments. Work includes using fluorescence methods to measure time-resolved pH of single aerosols and influenza virus infectivity decay, employing aerosol instrumentation to age influenza viral aerosols in controlled environments, and demonstrating plasma air treatment effectiveness in poultry facilities. Testing will progress from nonenveloped viral surrogates to enveloped viral surrogates to influenza aerosols.

The University of Bristol serves as a sub-recipient, with $424,923 allocated to fabricate and operate a QELEBS instrument coupled with a plasma source for installation at the University of Michigan and to explore natural decay dynamics of avian influenza across particle types and environmental conditions. The University of Bristol budget covers labor (principal investigator and postdoctoral researcher), materials and supplies, travel, and 15 percent indirect costs.

Performance occurs at Ann Arbor, Michigan, with the award period extending from February 2, 2026, through February 1, 2029.

The purpose of this research is to leverage recently developed aerosol diagnostic and experimental methods to create an improved understanding of viral aerosol natural decay in poultry production environments, while also advancing new and superior air disinfection technologies that meet the high ventilation needs of poultry production structures while also mitigating airborne transmission of avian influenza (AI). The primary beneficiaries of these research outcomes will be poultry and EGG producers for whom transmission of AI through ventilation systems is a priority. In this plan of research, the university of michigan in partnership with university of bristol (UK) will evaluate how aerosol PH is influenced by elevated ammonia concentrations found in air in poultry production environments. Furthermore, we will examine the influence of ammonia concentrations and aerosol PH on both the natural and engineered inactivation of viral aerosols. Fundamental experiments on natural decay and inactivation of viral aerosols will inform potential ways in which facility management practices can be leveraged to accelerate the loss of infectivity of aerosolized viruses. Applied experiments will demonstrate the effective performance of plasma air treatment in such environments. We will employ fluorescence methods to precisely measure time-resolved PH of single aerosols while also measuring influenza virus infectivity decay under identical conditions. We will employ novel and state-of-the art aerosol instrumentation to levitate and precisely age influenza viral aerosols within controlled environments to allow development of decay curves for viral infectivity as a function of time and ammonia (NH3) concentration. Viral targets will progress methodically from robust, easily cultured nonenveloped viral surrogates, progressing to enveloped viral surrogates, and finally to evaluations of influenza aerosols. Our use of aerosol fluorescence measurements as indicators of aerosol PH, in particular, represent a novel advance over approaches relying on bulk solution PH or deposition of aerosols on PH paper. Deliverables from this work will be data that allow facility management practices to be modified in ways that encourage rapid decay of viral aerosol infectivity, as well as performance data for the design of air disinfection technologies based on UV or non-thermal plasma technologies. The outcomes of these deliverables being utilized will be more secure poultry and EGG production.