Poster Presentation 64th International Conference of the Wildlife Disease Association 2015

A Two-Tier Ebola Virus Vaccination Strategy for Wild African Apes (#193)

Christopher Whittier 1 , Aisling Murphy 2 , Andrea Marzi 3 , Yoshimi Tsuda 4 , Friederike Feldman 5 , Michele Klailova 6 , David Greer 6 , Illhem Messoudi 7 , Peter Barry 8 , Allard Blom 6 , Heinz Feldmann 3 , Michael A Jarvis 2
  1. Cummings School of Veterinary Medicine at Tufts University, Grafton, MA, United States
  2. School of Biomedical and Healthcare Sciences, University of Plymouth, Plymouth, Devon, UK
  3. Laboratory of Virology, Division of Intramural Research and Rocky Mountain Veterinary Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
  4. Department of Microbiology, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
  5. Rocky Mountain Veterinary Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
  6. World Wildlife Fund, Washington, District of Columbia, USA
  7. School of Medicine, University of California at Riverside, California, USA
  8. California National Primate Research Centre, University of California at Davis, Davis, California, USA

The 2014 Ebola virus outbreak in West Africa is a stark example of the devastating impact of ebolaviruses after establishment of human-to-human transmission. African apes (chimpanzees and gorillas) are one main source of zoonotic Ebola virus transmission into the human population, but Ebola virus is also highly lethal in apes, and has resulted in substantial reductions in wild ape populations. Our aim is to reduce the impact of Ebola virus on wild apes and therefore also reduce this source of virus introduction into the human population by using vaccination to provide immunological protection for apes against Ebola virus. The assembled multi-disciplinary team represents a unique collaboration between conservationists, wildlife veterinarians and laboratories with expertise in vaccines and ebolavirus disease. We propose a two-tiered vaccination strategy comprising a short and a long-term aim to provide immunological protection of apes against Ebola virus – initially in habituated (accustomed to close human proximity) apes and then, using a novel ‘disseminating’ cytomegalovirus (CMV)-based vaccine, potentially in all ape populations. In the short term we will pilot vaccination of captive or semi-captive western lowland gorillas using a conventional human Ebola virus vaccine, with non-invasive antibody analysis in feces. With agreement from key stakeholders including the Central African Republic (CAR) Government, and based on our prior successful field vaccination campaigns, a comparable protocol will then be used to vaccinate habituated western lowland gorillas in Dzanga- Sangha Protected Area (DSPA), CAR. This short-term vaccination will provide these habituated animals protection from Ebola virus disease, and prevent them serving as a conduit for Ebola virus transmission into the human population. It will also establish a vaccination protocol that can be considered for use in other accessible ape populations. In the long term, our previous studies in mice and ongoing studies in non-human primates indicate that CMV-based vaccines can provide immunological protection against Ebola virus. The high species specificity of CMV and its ability to disseminate through its host population regardless of prior host immunity suggest that CMV has the potential for development as a ‘disseminating’ vaccine to achieve vaccine coverage of inaccessible, non-habituated wild apes. Our immediate long-term aim is to develop gorilla CMV (GoCMV) as a ‘disseminating’ Ebola virus vaccine to vaccinate all (including non-habituated) western lowland gorillas.