by The term zombie virus conjures images of reanimated corpses and apocalyptic outbreaks straight out of Hollywood, writes columnist James Williams. While fiction makes sense, reality presents a more dramatic picture: ancient viruses trapped in frozen soil or frozen ice for thousands of years are melting due to climate change, raising concerns about their potential threat to health the person. But before the panic sets in, let’s separate the fact from the fiction and get into the science behind these zombie pathogens.
Technically, a zombie virus is an informal term for any virus that is revived after a long period of dormancy. The main cause of concern is viruses trapped in permafrost, the permanently frozen ground in arctic regions. As global temperatures rise, this “deep freeze” gradually melts, potentially releasing viruses that have been dormant for thousands, even millions, of years.
Melting permafrost can deliver some amazing, mummified remains. In Siberia for example there are whole mammals exposed with intact meat, bones and fur. We can sample the DNA and there is even a project to recreate the mammoth using modern elephants as a carrier of a mammoth fetus. So far, scientists have succeeded in reviving several old viruses from dormancy, but none of them directly threaten humans. These viruses primarily infect single-celled organisms, which illustrates a critical point: not all ancient viruses can infect humans. Our immune systems have co-evolved with specific pathogens, which has made many resistant over time.
Although we have the ability to revive these viruses, we need to examine the ethics of doing so and what the benefits and risks might be. Studying resurgent viruses can help us understand their evolution, transmission, and purity, which could lead to better vaccines, diagnostics, and treatments for existing or similar viruses . Understanding how and why viruses emerged can help predict and prevent future outbreaks of similar pathogens. Some viruses can be used for beneficial purposes, such as cleaning up environmental pollutants.
As for potential risks, even with strong safety protocols, there is always the risk that the revived virus could accidentally escape from a laboratory and trigger a new pandemic. Reanimated viruses could be used by malicious actors for bioterrorism purposes, causing widespread devastation, and even if the reanimated virus is not highly contagious or virulent, it could interact with other organisms or the environment in unexpected ways, which which would lead to unintended consequences. Scientists will, however, perform a risk-benefit analysis, in which the potential benefits are carefully weighed against the risks, before attempting to revive any virus.
Research involving potentially dangerous pathogens should be conducted openly and transparently, with strong public oversight. Although we would like to think that all countries conducting this research will do so transparently, it is difficult to know what some countries, such as China, North Korea or Russia, are doing. Global cooperation and information sharing are therefore essential.
Although the zombie apocalypse scenario has little basis in science, it would be unwise to underestimate the risks. The great diversity of viruses locked in the permafrost remains unknown. We cannot predict how our immune systems might respond to novel pathogens. They are not just viruses that can live for thousands of years in a dormant state. Bacteria can also do the same and here, again, there is the risk of releasing new infectious diseases into the population. The zombie bacteria that have survived hibernation have so far shown no signs of increased danger. However, a growing concern is antibiotic-resistant bacteria, commonly known as zombie bacteria.
Focusing on zombie viruses or bacteria alone, the broader issue of emerging infectious diseases is looked at. Deforestation, intensive agriculture, and the illegal wildlife trade contribute to the emergence of new pathogens, emphasizing the interconnectedness of environmental and human health. Tackling these issues requires a multifaceted approach, from tighter regulations and habitat protection to improved pandemic preparedness.
While the immediate threat of zombie viruses may be exaggerated, they serve as a stark reminder of the complex dance between humans and pathogens. We must invest in research to understand these ancient viruses, develop robust surveillance systems, and prioritize global health initiatives. This requires international cooperation, increased funding for scientific research, and a shift towards environmentally responsible practices.
Dr James Williams is a senior lecturer in education at the University of Sussex
