Haris Malik

Project Title: Pre-empting Emerging Viruses: Infection Dynamics of a Transmissible Vaccine Candidate against Vampire Bat-Transmitted Rabies

In most Latin American countries, vampire bats are the primary source of human and livestock rabies mortality, resulting in losses exceeding US$30 million per year in the livestock industry, and an estimated 960 deaths/100,000 people in affected regions. Rabies has been classically controlled in Europe and North America via mass-vaccination of vertebrate reservoir populations such as dogs and foxes, however, for vampire bat-transmitted rabies virus (VBRV) these approaches are currently not applicable due to the lack of functional vaccine delivery methods to wild bat populations. Furthermore, current control measures such as bat culling and livestock vaccination have proven largely ineffective. One potential solution is the use of self-disseminating vaccines, whereby harmless viruses are modified to express immunogenic material from a target virus – whilst retaining transmission capacity. Using this novel technology, we could potentially pre-empt transmission to humans by eliminating viruses from animal sources like bats that have, historically, been inaccessible to manual mass-vaccination. Preliminary work has found a naturally occurring betaherpesvirus in vampire bats (DrBHV) that shows many characteristics of an ideal transmissible vaccine vector.

This project aims to develop a self-disseminating VBRV-vaccine by isolating and modifying DrBHV to express the rabies glycoprotein. Following this, I aim to undertake experiments in captive vampire bats to determine properties that underpin how a DrBHV-vectored rabies vaccine would be deployed. This project represents an exciting milestone in this emerging field; and, with success, will provide a framework for using self-disseminating vaccines to control other significant bat-borne zoonoses.