'Zombie deer disease' could spread to humans, warn scientists amid surge in US cases

Scientists issued a warning about the potential spread of a "zombie deer disease" to humans after hundreds of animals in the US were infected with the illness in the past year. Chronic wasting disease (CWD), characterized by symptoms such as drooling, lethargy, stumbling, and a blank stare in animals, was detected in 800 samples of deer, elk, and moose in Wyoming. Experts described the disease as a "slow-moving disaster" and called on governments to prepare for the potential transmission to humans.

“The mad cow disease outbreak in Britain provided an example of how, overnight, things can get crazy when a spillover event happens from, say, livestock to people,” said CWD researcher Dr Cory Anderson reported to The Guardian. Further, he added, "We’re talking about the potential of something similar occurring. No one is saying that it’s going to happen, but people need to be prepared.”

What happens in Zombie Deer disease?

During the mad cow disease outbreak in the 1980s and 1990s, the UK slaughtered 4.4 million cattle because of the spread of the disease, resulting from bovines being fed infected meat and bonemeal. The disease, usually fatal for cattle, infects the central nervous system, causing aggressive symptoms and a lack of coordination. Since 1995, 178 human deaths have been linked to the human variant of the disease. In 2017, humans were consuming 7,000 to 15,000 CWD-infected animals annually, according to the Alliance for Public Wildlife, with an expected annual increase of 20%. Dr. Anderson expressed concerns that thousands of people in Wisconsin might have consumed meat from infected deer.

Chronic wasting disease (CWD) proved extremely challenging to eradicate once an environment became infected, persisting for years in dirt or on surfaces. Scientists reported its resistance to disinfectants, formaldehyde, radiation, and incineration at 600°C (1,100°F). Following Ginkgo Bioworks' warning, illnesses transmitted from animals to humans were anticipated to cause 12 times as many deaths in 2050 as in 2020. The company highlighted the potential for more frequent zoonotic disease epidemics (spillovers) in the future due to climate change and deforestation. Between 1963 and 2019, epidemics increased by almost 5% annually, with deaths rising by 9%, according to the group’s research. The company warned that if these annual rates of increase continued, the analyzed pathogens would be expected to cause four times the number of spillover events and 12 times the number of deaths in 2050 compared to 2020.