In the quiet forests and grasslands of North America, a silent but disturbing phenomenon is developing: chronic wasting disease (CWD). The disease, often called “zombie deer disease,” is spreading silently through deer populations, raising concerns amongst scientists, conservationists and the general public.
This neurological disease, characterised by a myriad of symptoms including drooling, lethargy, stumbling and absent gaze, has now been detected in greater than 800 samples of deer, moose and moose in Wyoming alone, underscoring the size and urgency of the issue.
At the center of the CWD mystery lies a peculiar perpetrator: prions.
Prions are misfolded proteins that may cause normal proteins within the brain to misfold, resulting in neurological degeneration. This unique feature makes prion diseases particularly concerning because they’re extremely hardy and might persist within the environment for years, resisting traditional disinfection methods resembling formaldehyde, radiation, and combustion at extreme temperatures.
The spread of CWD poses serious ecological and potentially human health risks. Although there isn’t a clear evidence that CWD can directly infect humans, the chance stays a priority.
Prion diseases resembling Creutzfeldt-Jakob disease (CJD) in humans and “mad cow disease” in cattle have shown that they will cross the species barrier – with devastating consequences.
For example, since 1995, an outbreak of mad cow disease within the UK has resulted within the slaughter of tens of millions of cattle and the death of 178 people, which has been attributed to the human variant of the disease.
Although there aren’t any confirmed cases of CWD in humans, concerns arise from several aspects. First, research has shown that the prions liable for CWD can infect and reproduce in human cells under laboratory conditions, raising the spectrum of potential transmission.
Second, humans are already inadvertently exposed to potentially infected animals by hunting and eating them. Reports show that in 2017, humans ate between 7,000 and 15,000 CWD-infected animals per 12 months, with projections indicating a 20% annual increase.
In regions where CWD incidence is high, resembling Wisconsin, 1000’s of individuals can have unknowingly consumed meat from infected deer, highlighting the urgent need for risk-mitigation measures.
The situation is further complicated by the inherent difficulties in detecting and diagnosing prion diseases in humans. Unlike conventional infectious agents, prions don’t trigger an immune response, which makes them difficult to detect by conventional methods. This poses a serious obstacle to early intervention and efforts to contain the spread of the virus.
The potential for CWD to affect human health isn’t limited to direct transmission. The persistence of prions within the environment signifies that humans may additionally be exposed to indirect effects, resembling contaminated soil, water and other environmental sources.
Given the resilience of prions and their ability to persist within the environment for prolonged periods of time, the long-term effects of CWD on human health remain uncertain but require serious consideration.
In addition to direct health problems, the spread of CWD also poses significant ecological and economic risks. Deer hunting isn’t only a well-liked recreational activity, but additionally an important source of food and livelihood for a lot of communities.
The spread of CWD threatens to disrupt this delicate balance, potentially decimating deer populations and threatening food security in affected regions.
Moreover, the ecological effects of CWD extend beyond deer populations and affect entire ecosystems. Deer play a key role in shaping vegetation dynamics (the change and evolution of plant communities over time) through browsing and grazing.
Their decline could have cascading effects on plant communities, soil health and other wildlife species that depend on deer as a food source or habitat modifier.
In Europe too
It is price noting that although there have been no reported outbreaks of CWD within the UK, it was diagnosed in wild deer in Norway in 2016, marking the primary cases of CWD in Europe.
This development highlights the potential for CWD to spread beyond its current range and underscores the necessity for international cooperation in monitoring and controlling the disease.
Meeting the various challenges posed by CWD requires a comprehensive and coordinated approach.
This includes strengthening surveillance and monitoring to trace the spread of the disease and implementing stringent biosecurity measures to forestall further transmission – resembling controlling the movement of deer and moose populations, conducting regular testing to observe the incidence of the disease, and promoting responsible hunting practices to minimizing the chance of transmission.
Further research can also be needed to raised understand the dynamics of disease transmission, its ecological effects and potential impacts on human health.
Ultimately, the CWD spectrum highlights the interconnectedness of ecosystems and human health. By listening to scientists' warnings and taking decisive motion to cut back risks, we will work to guard each wildlife and human populations from the insidious grip of CWD and other emerging zoonotic diseases.
In doing so, we honor our commitment to protecting the health and well-being of our planet and its inhabitants for future generations.
Samuel J. White, Senior Lecturer in Genetic Immunology, Nottingham Trent University and Philippe B. Wilson, Professor of One Health, Nottingham Trent University
This article has been republished from Conversation under Creative Commons license. Read original article.
Image Source: Pixabay.com
