Along with trendy "greenness" and various environmental protection efforts, alternative recreational programs such as eco-tourism have received their fair share of growth. While their intentions are clearly benevolent, the outcome of such activity may be harming wild animals. While transmission of infectious diseases between two dissimilar species is very rare, humans are close enough physiologically to apes to share several devastating diseases. This unfortunate fact has become very evident as eco-tourists have been unknowingly spreading pathogens to these noble forest dwellers and wreaking havoc upon their populations.
Viral infections are usually very specific to the host they target. On a cellular level, a virus binds to a cell and takes control of its processes before injecting a new, foreign genetic code. The disabled cell has no choice but to carry out whatever biological instructions are encoded in the viral DNA. Almost always, the code forces the cell to produce hundreds to thousands of more viruses. Soon after, the cell bursts, unleashing the viral copies to infect new cells.
Once the virus has commandeered the cell, there is little that can be done to save it. Viruses can, however, be stopped before they reach that stage. These microscopic semi-living artifacts of DNA and protein have evolved over millions of years to only bind to specific proteins found on a cell's outer membrane. If that protein is damaged, altered, or otherwise missing, the virus cannot bind - it cannot infect the host. This phenomenon has manifested itself in the group of Northern Europeans who are seemingly immune to HIV infection. They possess a gene that produces a mutated CCR5 protein, the membrane protein necessary for HIV to infect an organism.
This same phenomenon is responsible for preventing transmission of viral disease across dissimilar species. For the most part, receptor proteins are different enough between species to prevent the very biologically specific viruses from infecting multiple host organisms. Rabies and several strains of the influenza virus (i.e. Avian Flu and Swine Flu) are notable exceptions to this rule.
Unfortunately, apes in popular eco-tourism destinations are bearing the brunt of our species' similarities. Furthermore, eco-tourists aren't the only culprits; researchers and other scientists whose missions depend on close contact with gorillas, chimpanzees, and others were also found to be harmful vectors of disease. Ebola, HIV, polio, yaws (a non-sexually transmitted form of syphilis), and even anthrax are known to cross-infect both humans and apes. Several groups of endangered chimps in Africa's Cote d'Ivoire all succumbed to either the human respiratory syncytial virus (HRSV) or human metapneumovirus (HMPV) after recent encounters with teams of researchers. Fabian Leendertz, wildlife epidemiologist at the Robert Koch Institute and the Max Planck Institute, claims that "virtually all diseases that can harm us can harm the great apes."
These findings are scientifically relevant since they represent some of the first fully confirmed cases of disease transmission between apes and humans. Scientists have conjectured that HIV originated among apes many years ago and these recent unfortunate human disease outbreaks are helping to confirm several of today's most virulent ailments' origins. The negative effects of close proximity to these animals must be carefully considered, however. Poachers have long been a formidable enemy of gorillas and other apes. Eco-tourists and various research efforts have successfully thwarted many poachers by either drawing political attention to the apes' plight and economic value, or simply by their presence.
Most scientists accept that the recent mortality rate increase caused by human diseases has taken a much smaller toll on overall populations than poachers would have otherwise taken.
If anything, the attention being generated by these outbreaks has raised awareness. Many researchers are taking precautions against spreading human diseases to apes, such as wearing surgical masks, keeping their distance, and washing their boots more frequently.
Hopefully these safety measures can help protect the very apes that researchers and tourists are trying to save.
Be the first to comment on this article!