A 'zombie deer disease' is infecting animals in the US. But could it spread to humans too?

We've got a new addition to the list of apocalyptic-sounding diseases – a "zombie deer disease" that has been infecting hundreds of animals in the US, with a growing possibility it might make the jump to humans.

What

Chronic wasting disease (CWD), colloquially referred to as "zombie deer disease," has become a growing concern among scientists as it has infected hundreds of animals in the United States over the past year. The recent discovery of the disease in Yellowstone National Park has heightened worries about the potential transmission to humans.

• CWD is a prion disease, a class of infectious agents composed of misfolded proteins. 
• It has been observed in various ungulate species such as deer, elk, reindeer, and moose, affecting regions in North America, Canada, Norway, and South Korea. 
• The disease is characterized by symptoms like drooling, lethargy, stumbling, and neurological abnormalities, leading to significant weight loss.

Spillover to humans

Despite primarily affecting animals, there are concerns among scientists that CWD could eventually pose a threat to human health. 

• The gradual nature of the disease has led experts to characterize it as a potential "slow-moving disaster."
• While there have been no confirmed cases of human infection (spillover) yet, epidemiologists caution that the absence of such cases does not rule out the possibility of it happening in the future.

Mad Cow Disease 2.0

The comparison to the mad cow disease outbreak in Britain serves as a reminder of the unpredictability of spillover events from animals to humans. 

• Reflecting on the devastating impact of mad cow disease in the UK, where millions of cattle were slaughtered, experts express concern about the potential consequences if CWD were to spread to humans.

Dr Cory Anderson, a CWD researcher, emphasizes the importance of preparedness in an interview with the Guardian, even though the likelihood of human transmission remains uncertain. 

Impossible to kill

The cherry on top? There's no foolproof way to eradicate this menace. Once it contaminates an area, it proves extremely difficult to eliminate, persisting for years in soil or on surfaces. Moreover, the prion has shown resistance to common disinfectants, formaldehyde, radiation, and even incineration at high temperatures.

The CDC acknowledges the potential risk to humans, citing animal studies that suggest a risk to certain non-human primates exposed to CWD-infected materials. Since 1997, the World Health Organization has emphasized the importance of preventing agents of known prion diseases, including CWD, from entering the human food chain.

As the world faces increasing challenges related to zoonotic diseases, the emergence and spread of CWD serve as a grim reminder of the importance of monitoring and addressing such potential threats.