“We are at a new horizon for ape conservation”
Dr. Peter Walsh VACCINAPE
We’ve known for a long time that poaching and habitat loss were causing great declines in ape numbers, but what we’ve found out recently is that infectious disease is also causing steep declines in many ape populations.
There are really two kinds of disease that are causing these de- clines. There are what you might call natural diseases, like the Ebola virus, which has killed about a third of the gorillas in the world in about the last fifteen years and there are also diseases that are being introduced to gorillas and chimpanzees from hu- mans. For instance, we have had a series of respiratory disease outbreaks at tourist and research sites over recent years that have killed a lot of gorillas and chimpanzees. That, in particular the fact that these diseases are coming from humans, gives us a particular impetus to do something about this. Because if we don’t, gorillas aren’t going to go extinct tomorrow, and neither will chimpanzees, but in the next twenty, thirty, forty years, we are going to lose most of the populations, or we will be left with a very small handful.
It is also important to recognize the potential threat to African ape conservation posed by naturally occurring pathogens. Recent studies suggest that Ebola may be contributing substantially to great ape declines in central Africa (see chapter Ebola; Leroy et al., 2004). Also troubling are findings of higher mortality and lower reproductive success in wild chimpanzees infected with SIV, long thought to be non-pathogenic in apes, compared to un- infected individuals (Keele et al., 2009). Lastly, anthrax infections with no known link to humans or livestock have killed wild goril- las and chimpanzees at multiple sites (Leendertz et al., 2006).
What I, and a group of other people have been doing, is looking at options to prevent those disease deaths. In particular, we are look- ing at vaccination; what we are trying to do, is to take human vac- cines and adapt them for use on wild apes. Now this has only been done once or twice before, and so we are at a sort of new horizon for ape conservation. What we are trying to do is take a very scientific look at the process and be very safe, and make sure that the benefits of vaccination outweigh the costs. We are doing a series of tests and trials involving a lot of experts from different fields, virologists, primatologists, veterinarians, and we are trying to come up with a plan that will allow us to take the many human vaccines that are now available, and in development, and use them on apes in the wild. Right now, we have two pilot projects, we are adapting an Ebola vaccine and a measles vaccine. The measles vaccine is very safe and it has been used on hundreds of millions of children and we are using that as a sort of proof of principle, and then we are also trying to move in with the use of an Ebola vaccine, and that will happen over about the next two years. If you’d like to hear more about these efforts, you can go to www.vaccinape.org.
Our capacity to understand the role of anthropogenic and natural selective pressures on wild primate populations is challenged by the need to effectively form multidisciplinary teams bridging conservationists and researchers that can re- spond adaptively to the development of integrated theory and next-generation methods and technologies while maintaining standardization to allow for meaningful meta-analyses and model formulation embracing animal health, human health and environmental health issues (Leendertz et al., 2006; Gil- lespie et al., 2008).