Scientists warn 'zombie deer disease' could spread to humans

CWD, also known as “zombie deer disease,” is a progressive, degenerative brain disorder that has no cure or vaccine and can be fatal. It has been found in deer, elk, moose, and elk in the northern United States, Canada, Norway, and South Korea.

CWD is caused by prions, unusual transmissible pathogens that alter the host's brain and nervous system, causing infected animals to drool, become lethargic, collapse, and stare blankly.

Experts described the disease as a “slow-moving disaster” in a recent report by The Guardian.

The disease is “always fatal, incurable, and highly contagious,” explains Dr. Cory Anderson, a CWD researcher at the University of Minnesota, warning that it is nearly impossible to eradicate once it is introduced into the environment. Scientists note that CWD is resistant to disinfectants, formaldehyde, radiation, and 600°C incineration, and can survive in dust or on surfaces for years.

The disease was detected in about 800 samples collected from deer, elk, and moose across Wyoming in 2022, according to Breanna Ball of the U.S. Fish and Game Service. She said the CWD infection rate has increased compared to previous years.

Scientists are particularly concerned that the disease appears to have entered Yellowstone National Park in recent months. The park’s ecosystem supports the largest and most diverse population of large wild mammals on the continent, explains Dr. Thomas Roffe, former chief animal health officer for the U.S. Fish and Wildlife Service. Failure to contain the spread of CWD could expose millions of people who visit Yellowstone each year to the disease.

A US Geological Survey published in early December 2023 found that the disease is currently present in 32 US states as well as three Canadian provinces.

To date, there have been no reported cases of CWD spreading to humans, although an estimated 15,000 infected animals were consumed by humans in 2017, according to the Alliance for Public Wildlife.

However, epidemiologists in the US and Canada warn that it is only a matter of time because the disease is part of a family of fatal neurological disorders, including mad cow disease or bovine spongiform encephalopathy (BSE).

"The outbreak of mad cow disease in the UK is an example of how chaos can occur overnight when a disease spreads from cattle to humans," The Guardian quoted Dr. Cory Anderson, a CWD researcher at Minnesota State University (USA).

"We're talking about the possibility of something like this happening. No one is saying it's going to happen, but it's important that we're prepared," Dr. Anderson stressed.

Britain had to cull 4.4 million cattle after mad cow disease spread in the 1980s and 1990s, caused by cattle being fed meat and bones from infected animals.

The disease attacks the central nervous system in cattle, causing them to behave abnormally, have difficulty moving and lose weight before dying.

Since 1995, 178 people have died from infection with the variant mad cow disease.

Minh Hoa (t/h)

Source