A study warns that by 2050, diseases transmitted from animals to humans may kill at least 12 times more people than in 2020.

Epidemics caused by certain zoonotic infectious diseases, also known as spillovers, may become more frequent in the future due to climate change and deforestation, says American biotechnology company Ginkgo Bioworks.

Researchers found that the number of epidemics increased by almost 5% each year from 1963 to 2019, with a 9% increase in mortality.

"If these annual growth rates persist, we expect the analyzed pathogens to cause four times more spillover events and 12 times more deaths in 2050 than in 2020," the study says.

However, researchers noted that these figures are likely underestimated because COVID was not included in the study, as it did not meet their strict inclusion criteria.

The World Health Organization (WHO) has stated that it is "likely" that the virus was transmitted to humans from bats, but some scientists dispute this theory.

The study, published in the BMJ Global Health journal, analyzed historical trends in four specific types of diseases. These included filovirus diseases, such as Ebola and Marburg viruses, atypical pneumonia, coronavirus 1, Nipah virus, and Machupo virus.

Researchers studied over 3,000 outbreaks from 1963 to 2019 and identified 75 spillover events in 24 countries. These included outbreaks reported by WHO, events since 1963 resulting in 50 or more deaths, and historically significant events, including the influenza pandemics of 1918 and 1957.

In total, these events led to the deaths of 17,232 people, with 15,771 deaths attributed to filoviruses, primarily occurring in Africa.

The researchers added that data from recent epidemics caused by zoonotic spillovers suggest that they are "not deviations or random clusters" but follow a "decades-long trend in which spillover events have become larger and more frequent."

The team concluded that "urgent actions are needed to mitigate the substantial and growing risk to global health" based on historical trends.