USDA and PARC documents reveal biological mass-spray vaccine testing

Documents from the U.S. Department of Agriculture (USDA) and the Palo Alto Research Center (PARC) reveal plans and funding for biological spray technologies involving bat vaccines prior to the COVID-19 pandemic.

A July 2019 USDA Environmental Assessment detailed plans to field-test an unlicensed experimental raccoon-poxvirus-vector bat vaccine. The plan involved applying vaccine-laden glycerin jelly to bat houses or directly to bats “by hand or by spraying” so they would ingest the material through grooming.

Records indicate that the U.S. government funded PARC to develop and test automatic spray technology for the mass delivery of vaccines and other compounds to free-ranging bats. This work was linked to the DEFUSE project, a proposal submitted to the Defense Advanced Research Projects Agency (DARPA) that discussed using raccoon poxvirus vectors for delivery to bats.

According to USAspending records, the U.S. government paid PARC $198,940 on May 13, 2020, to “DEVELOP&TEST SPRAY DEVICES,” a contract that remained active through December 31, 2021. The DEFUSE project characterized its technology as capable of “large area and high throughput aerosol delivery” of bioactive formulations, noting potential applications for the “large area inoculation of animals/humans.”