Article: "Prediction of Spillover and Interventional Animal Vaccination to Prevent Emerging Pathogen Threats in Current and Future Zones of US Military Operation"

Preempt Program PictureDARPA (Defense Advanced Research Projects Agency) issued a Broad Agency Announcement in January 2018 entitled "PREventing EMerging Pathogenic Threats - PREEMPT" to "a new layer of medical preparedness to combat emerging infectious diseases".  The basis for DARPA interest in this topic is that almost 60% of emerging infectious diseases in humans are transmitted from an animal species harboring the pathogen that is then subsequently transmitted to humans, known as a zoonotic transmission.  Emerging infections also result from insect species, such as mosquitos, that transmit novel viral pathogens into humans, such as the Zika virus that is carried by mosquitos.

We confront this seasonally every year as variant influenza viruses that normally infect wild and domesticated birds, and/or swine acquire the ability to infect humans, which can efficiently transmit the influenza virus from the infected person to close contacts.  Other examples affecting human health include HIV, where HIV-1 appears to have jumped from chimpanzees to humans and HIV-2 jumped from nonhuman primates in western Africa to humans, Ebola virus, which appears to be an infection of fruit bats and possibly other species, and Lassa Fever virus, which is endemic in rat populations in western Africa.  

Zoonotic diseases result in millions of human deaths every year, and the scope of the challenge is increasing due to increased livestock and poultry production, increases in human deforestation of previously undisturbed natural environments, and increases in globalization, temperature, and population.  Responses to zoonotic infections are largely reactive once a novel outbreak is recognized, although the process of generating new vaccines for the next flu season are based on characterizations of influenza strains currently circulating in humans.  One major impediment in responding to novel zoonotic infections is that animal-to-human transmissions are unpredictable, meaning that the capability to better predict when a virus might make the zoonotic jump into humans is not currently available. 

The overarching goals of DARPA's PREEMPT program are to develop (1) better modeling capabilities to prepare in advance for imminent zoonotic viral infections, and (2) novel technologies that can reduce the potential of animals and insect species to serve as vectors that can transmit emerging viruses into humans.

Dr. Peter Barry is a Co-Principal Investigator with Dr, Brian Bird of the One Health Institute at UC Davis, Dr. Scott Nuismer (Univ. of Idaho), and Dr. Michael Jarvis (Univ. of Plymouth, UK) on a DARPA-funded PREEMPT project entitled "Prediction of Spillover Potential and Interventional En Masse Animal Vaccination to Prevent Emerging Pathogen Threats in Current and Future Zones of US Military Operation".  The goals of the project are twofold.  The first is to better predict the likelihood of emergent pathogens, and the second is to develop preemptive countermeasures to reduce the risk of viral exposure by US military personnel.  This is a project that could only have come out of UC Davis given our strengths in animal modeling of human diseases (CCM and the CNPRC), and the critical foundation established for investigating at the nexus of animals, humans, and the environment for potential zoonotic infections (One Health Institute).  This project will focus on novel strategies to model the spread of Lassa Fever Virus from Mastomys rats to humans in Sierra Leone, which resides in the middle of the Lassa Fever zone in western Africa, and the spread of Ebola virus to humans.  In addition to better modeling capabilities, a co-equal outcome of this project will be the ability to vaccinate animals directly before the viral pathogens can be spread to humans.