Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now

×

New research provides recommendations for the ethical and safe development of zoonotic vaccines

Seven commitments were proposed to help ensure the safely designed and staged transparent development of vaccines

New research from the Royal Veterinary College (RVC), exploring the potential development of purposeful transmissible wildlife vaccines to reduce the risk of viral zoonosis affecting humans, has shared recommendations to ensure vaccines are intrinsically safe and ethically designed and developed.

A zoonosis is a pathogen that is naturally transmissible from animals to humans. Transmission of these pathogens from animal hosts to humans can be through direct or indirect routes. Zoonoses comprise a substantial proportion of new and existing diseases in humans and are of increasing concern in a globalised world. Several known zoonoses have been identified as priority pathogens by the World Health Organisation due to their epidemic potential. 

Recently, transmissible vaccines, which are intentionally developed to spread within a target population, have been considered as a means to control the transmission of zoonotic diseases, reducing the risk of pathogen spillover into human populations. By delivering immunisation at scales sufficient to interrupt pathogen transmission, there is the potential to transform the management of public health challenges, wildlife conservation and animal welfare.

However, the development of these vaccines will require the modification of viruses that would be intended to spread in nature. This raises concerns about technical feasibility, safety and security risks, regulatory uncertainties and ethical decision-making.

A multidisciplinary cohort of researchers was convened, including David Simons, a recent PhD graduate at the RVC, alongside bioethicists, disease ecologists, evolutionary biologists, immunologists, sociologists and virologists. Throughout the multi-day event, the researchers appraised the potential ecological and societal risks associated with the transmission of an engineered viral vaccine.

Subsequently, the researchers proposed seven commitments for the sector, beginning with a priori decisions on vaccine design and continuing through to stakeholder co-development, to help ensure the safely designed and staged transparent development of vaccines.

These included:

  • Vaccines will use naturally occurring and host-specific viruses as vectors that would be sourced from and returned to their natural host species after antigen insertion
  • Genetic modifications that increase host range, pathogenicity, or transmissibility, or create secondary hazards will not be intentionally pursued
  • Technologies that could plausibly be harmful if applied to a human virus should be avoided
  • Development will be staged with defined checkpoints and carried out within appropriately controlled environments
  • Unintended spread and consequences will be monitored throughout the development stages, with contingency plans
  • Development will be transparent and community-led
  • Safety standards will approach the strictest standards of partner nations involved

The commitments are designed to increase the likelihood that the potential risks of vaccine transmission are outweighed by benefits to conservation, animal welfare and zoonosis prevention. They are designed to serve as a conservative starting point which will then be evolved with further research alongside societal attitudes, scientific evidence and technology.

David Simons, recent PhD graduate at the RVC, said: “Deliberately transmissible wildlife vaccines to combat endemic and emerging zoonoses are not currently in use. However, they represent a potentially vital novel technological development to improve the health of individuals living in endemic settings for several important pathogens where there is currently no effective treatment or prevention, for example, Lassa fever in West Africa.

“We strongly encourage scientists and vaccine developers to integrate and advance our seven commitments for transmissible vaccines to ensure safe, transparent and equitable implementation of this exciting intervention.

“Identification of suitable zoonotic pathogens for targeted vaccine development is underway, and the adoption of these commitments and any future commitments will ensure that implementation of this exciting technology will benefit those who need it most.”

The full paper can be accessed here.

Have you heard about our
Membership?

The number one resource for veterinary professionals.

From hundreds of CPD courses to clinical skills videos. There is something for everyone.

Discover more