Scientists have spotted four types of animal-to-human infections which are spreading at an “exponential rate” – and could pose a major threat to global health by 2050.
According to an analysis of 60 years of historical data published in the BMJ Global Health, this small group of viruses could collectively kill 12 times more people in 2050 compared to the deaths recorded in 2020, at the height of Covid.
The group includes:
3. Nipah virus, which causes a Nipah infection
4. Machupo virus, which can cause viral hemorrhagic fever
How did the scientists come up with this conclusion?
This group of specialists spotted a general pattern of increasingly larger and more frequent spillover epidemics, when infections move from animals to humans, through their research.
The scientists noted that these epidemics have generally become larger and more frequent over the last six decades.
And, to make things worse, climate and land use changes will worsen this cross-over infection, too, due to increased population density and connectivity.
Animal-to-human infections, known as zoonotic, have caused most of our modern epidemics.
However, they’re difficult to characterise because there is not enough historical data on the frequency and severity of the crossover infections.
Still, the scientists’ database looked through a wide range of official sources.
They included epidemics recorded by the World Health Organisation, any disease outbreaks caused by a viral pathogen that killed 50 or more people, and historically significant outbreaks, like the flu pandemics of 1918 and 1957.
It was then that the scientists noted four viruses have been increasing by almost 5% and 9%, respectively, every year between 1963 and 2019, excluding the Covid pandemic.
They spotted 75 spillover events in 24 countries during that time frame.
What does this mean for global health?
That means all four viruses pose “a significant risk to public health and economic or political stability”.
The researchers noted: “If these annual rates of increase continue, we would expect the analysed pathogens to cause four times the number of spillover events and 12 times the number of deaths in 2050 than in 2020.”
In fact, this could be an underestimate, because of the strict inclusion criteria for pathogens and ruling out Covid.
The study suggested spillover events are “not an aberration or random cluster”, but a regular trend.
The scientists subsequently called for measures to up global prevention, preparedness and resilience, suggesting that their findings prove “urgent action is needed to address a large and growing risk to global health”.