Five diseases that originated in animals and were transmitted to humans could cause 12 times more human deaths in 2050 compared to 2020, according to research that calls for “urgent action” to combat the growing health threat posed by zoonotic infections.
Concerns about this type of disease have increased greatly since Sars-Cov-2 emerged in China at the end of 2019 and spread rapidly around the world. A study published by BMJ Global Health on the 2nd found that environmental and population changes over the last six decades are driving the growth in the number of such “transmission events” as the one that caused the new coronavirus pandemic.
“It’s not just that we are seeing more of these events, but that they are persisting longer and generating more deaths,” said Ben Oppenheim, co-author of the BMJ paper and senior director at US company Concentric by Ginkgo, which works with governments to monitor early warning of pandemics. “This points not only to the risk, but to the magnitude of work needed to mitigate it.”
Efforts to detect disease outbreaks in areas of high population density have already been intensified. However, the researchers recommended other measures, such as increasing the assessment of pandemic risks driven by climate change and deforestation.
A separate study published by Science also on the 2nd of this month found that mpox, the virus that triggered an international health emergency last year, has been transmitted between people for much longer than previously thought.
Concentric researchers focused on a group of “high consequence” pathogens: the filoviruses Ebola and Marburg —which cause hemorrhagic fevers—, Nipah, Machupo and Sars-CoV-1, a genetic ancestor of Sars-CoV-2. They used a database with more than 3,150 outbreaks and epidemics from 1963 to 2019.
The viruses caused a total of 17,232 recorded deaths across 75 transmission events in 24 countries across Africa, Asia and South America. The numbers of outbreaks and deaths increased at an “exponential rate” over the 56-year analysis period through 2019 , the researchers found.
If these trends continue, the group’s transmission events will be four times higher and the number of deaths 12 times higher in 2050 than in 2020, they concluded — a prediction they classified as “conservative.” The increase reflects how environmental changes and growing population density are increasing interspecies contact and human-to-human infections.
Separate new research into mpox, the disease formerly known as monkeypox, found mutations that suggest it has been circulating in humans and interacting with their immune systems since 2016. This contradicts assumptions prior to the 2022 emergence that mpox cases they were mostly independent rodent-to-human transmission events, with only limited cross-infections between people.
Efforts to monitor and suppress mpox, which was initially identified in captive monkeys, will need to be intensified to control its spread, the international team of researchers concluded. “Surveillance needs to be global if [o vírus] is to be eliminated from the human population and then prevented from resurfacing,” they wrote.
The World Health Organization (WHO), which stopped classifying smallpox as a global health emergency in May, has proposed a global agreement on pandemic preparedness and is working with other agencies on early warning, prevention and control of zoonotic disease threats. .
The research suggested that more attention should be paid to preventing pandemics rather than responding to them, according to Professor James Wood, an infectious disease expert at the University of Cambridge.
“Our global human impacts, such as the way we grow our food and exploit natural resources… are progressively increasing the risk of future pandemics similar to Covid-19,” he said. “These considerations are politically and economically complex, but we are ignoring them at our peril.”