The Case for Wild Animal Vaccination

It is in large part due to the inescapable, debilitating, and agonizing effects of disease that we believe wild animals might live truly miserable lives. Not only does it cause a significant amount of suffering for infected animals, disease is also extremely widespread across all species and populations. As such, reducing, controlling, and eliminating diseases impacting wild animals has a huge potential to alleviate suffering and improve lives.

Fortunately we’ve already begun working to control disease in the wild, and showing that this avenue of approach is extremely fertile for more direct attempts to help animals in the future. Most of our attempts to treat disease, while they are ultimately good for the animals in question, have thus far been to protect human interests, such as pets and livestock, either from endemic diseases in these populations, or those which may be transferred from wild animals to domesticated ones. Reducing disease in wild animals can be good both for people and animals.

Targeted vaccination programs represent the majority of successful human reductions of wild animal disease. Contrary to how human vaccination is done, it is possible and indeed even desirable to use hands-off forms of vaccination for wild animals. Such vaccines are typically in the form of baits—edibles which, when consumed by a member of the target species, deliver a vaccine to the animal in question. This method has become the norm in wild animal vaccination since it causes no harm to the animal in question compared to injection by syringe or dart, and because baits can be distributed throughout a target species’ territory without the need to actually seek out individual animals.

In this way, we have partially addressed the tractability of vaccinations as a way to promote welfare, and shown it to be greater than intuition might suggest. It remains to be seen, however, whether vaccinations are legitimately effective in reducing disease, and thus increasing welfare. Fortunately there are numerous examples of successful vaccination programs around the world, not to mention ongoing research into the development of new vaccines.

The rabies vaccine is perhaps the most well-known example of this type of intervention. Although the rabies vaccine has been used for companion animals like dogs and cats, it has been far more important for wild animal populations. Rabies vaccination programs have long been employed to protect livestock and human populations alike, leading to the near total elimination of rabies in some parts of the world. In Estonia, for example, the disease was completely eradicated in their raccoon population using oral baits over the course of several years. In Texas, there has been similar success with a vaccination program targeting rabies in coyotes. Thanks to decades of distributing oral vaccines, the number of reported cases of rabies has fallen from 250 a year, to zero, a number which has stayed constant for the past ten years.

In fact, wild animal vaccination has become fairly routine in many countries around the world. New Zealand, Australia, the UK, and Spain have all executed successful vaccination programs to protect against Bovine Tuberculosis, in possums, badgers, and wild boar respectively. The UK has also had an intensive vaccination program for avian influenza which has been successfully deployed in a number of regions for many years. What’s more, these programs don’t need to continue indefinitely, as once disease is eradicated in one region, attention can be be directed towards other suffering populations, since without any disease agents in a region the disease has no way to reappear.

Fortunately as these once ubiquitous diseases are eliminated forever new vaccines are constantly being developed to address the next. Research into vaccines is continuously happening around the world, such as recent research into vaccinations for wild mice to prevent the spread of Lyme disease. Another study was conducted recently in deer, in order to test a vaccination against Chronic Wasting Disease, or CWD. Given that CWD is caused by prions, rather than bacteria or viruses, the success of this research is all the more inspiring, as yet another class of disease can now be protected against.

These results represent only a fraction of the numerous victories humanity has won against disease, yet they suffice to illustrate a hopeful realization: wild animal vaccination is genuinely effective and viable. Yes, there are still hurdles to overcome, and much research to be done, especially regarding the ecological role of disease in nature, but from the perspective of reducing suffering there is demonstrated potential. However inadvertently, humanity has found itself on the path to stewardship.




Cara Ouellette