Location: Zoonotic and Emerging Disease Research
Project Number: 3022-32000-027-007-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 22, 2023
End Date: Jul 21, 2027
Objective:
The increasing frequency of outbreaks of emerging and re-emerging diseases reflects the interconnected nature of human, animal, and environmental health. Local and regional outbreaks present a greater threat to human and animal health everywhere. Species in close contact at the human-animal nexus, namely humans and the animals they raise, represent high-risk populations for cross-species spillover events. Crimean-Congo Hemorrhagic Fever virus (CCHFV) and Henipaviruses are two key examples of emerging infectious diseases that represent a threat to livestock, wildlife and humans with complicated zoonotic origins. CCHFV is a tick-borne virus known to cause hemorrhagic fever with a case fatality rate ranging from 9-50%. The geographic distribution of this virus remains only partially characterized with cases found across the mediterranean through central Africa and China. As wild and domesticated animals such as cattle, goats, and sheep are amplifying hosts for the virus, those who work closely with these animals are at high occupational risk for the virus. Similarly, henipaviruses are rare but fatal viruses spread via bats to livestock animals which in turn infect the people who care for them. Hendravirus, observed in Australia in 1994 was spread from flying fox bats to horses and then to seven individuals, and caused high fatality among both groups. Nipahvirus shares a similar trajectory from wild bats to domesticated animals and eventually to humans. Nipahvirus was first discovered in 1999 on a pig farm in Malaysia. Both viruses can cause encephalitis and case fatality rates from 40-75%.
One of the greatest challenges to monitoring the geographical distribution and emergence of these pathogens are sensitive and specific diagnostic assays that can be used on samples collected from humans and from animals. Currently there are limited assays available. The majority of available tests are LDTs or laboratory developed tests. Often these tests are not available outside the individual labs, have limited validation and often subject to lot to lot variabilities. This projects seeks to develop multiplex assays to evaluate the presence of IgG to high risk emerging zoonotic pathogens.
Approach:
Aim 1: Develop individual assays for the magpix or luminex platform to: Nipah, CCHF and Ebola virus in human serums. University of HI has extensive experience in development of multi-plex assays for the luminex and magpix platforms. Currently the team has developed candidate assays for coronaviruses and filoviruses. The team will work to develop CCHF, Nipah and Ebola assays. The glycoproteins will be used as the primary targets. Commercially available monoclonal antibodies will be used for development and characterization of assays. Where possible immune serum from partners will be used for pilot evaluations.
Aim 2: Adaptation of individual assays to a species agnostic or multiple species assay. To develop assays that can be used from samples from multiple species a conjugate protein A will be used as an alternative to a species specific detection antibody. In addition there are limited commercial antibodies with reported broad reactivity across multiple species. These will also be evaluated if the protein A approach fails.
Aim 3: Development of a multiples species agnostic or multi species assay
Individual assays will be combined for a multi-plex approach. Candidate multiplex assays will be optimized to prevent loss of sensitivity and specificity. The target will be a multi-plex assay containing 4-8 targets.
Aim 4: Field testing of species agnostic multi-plex assay. The lead candidate assay will be deployed to field sites for evaluation. Samples previously identified as positive and suspect samples will be evaluated. The finalized assay will be published.
