Spillover by David Quammen. The book discusses zoonotic diseases, which are illnesses that originate in wild animals and are transmitted to humans, often through an intermediate host species.
In Africa, zoonotic diseases sometimes spread when people consume wild animals such as gorillas or chimpanzees. One notable example in the book is the Hendra virus outbreak in eastern Australia. This virus originated in bats, specifically flying foxes, which would defecate near areas where horses fed. Horses became infected by contact with bat droppings, and when an infected horse died, the virus was present in its bodily fluids. Humans contracted the virus through direct contact with the horse’s respiratory secretions or fluids, not just blood.
In this outbreak, a few horses became sick, with some showing signs of brain damage. The first horse to die was buried without any forensic investigation because the owner did not want to pursue expensive tests. Unfortunately, one of the people who cared for the horse later fell ill as well.
The book goes on to explore other zoonotic diseases. Published in 2012, it made a remarkable prediction that a future pandemic could emerge in places like southern China. This was long before the COVID-19 pandemic, which began at a wet market in Wuhan, China, making the book’s prediction particularly striking.
The Marburg virus, another zoonotic disease, caused several deaths in the late 1990s, notably during an outbreak in the Democratic Republic of Congo. One of the most dramatic cases of zoonotic transmission is Ebola. There are different strains of the Ebola virus, and not all of them cause illness in humans. For example, the Reston virus, which appeared in the U.S. in 1989, did not make humans sick. However, a deadly strain of the Ebola virus, the Zaire strain, caused hundreds of deaths in Kikwit, Zaire (now the Democratic Republic of the Congo) in 1995. Scientists believe an intermediate host is needed for Ebola to transmit to humans.
The book made a striking prediction that an epidemic could soon emerge, possibly in China. Although Professor Robert Webster primarily focused on influenza and bird flu, he also understood that coronaviruses have an inherent ability to evolve. This trait makes them a significant threat to humanity.
Additionally, Professor Donald Burke anticipated the SARS epidemic six years before it occurred. In this book, published in 2012, Burke interestingly describes scenarios that later became a reality with the COVID-19 pandemic.
To prepare for the next epidemic, several actions are essential:
– Identify which virus groups to monitor.
– Develop field capabilities to detect spillovers in remote areas before they become outbreaks.
– Build organizational capacity to control outbreaks before they escalate into pandemics.
– Strengthen laboratory tools and skills to identify viruses quickly.
– Create vaccines and therapies swiftly.
The book also explores whether we, as humans, are an “ecological outbreak” on Earth. The global population has grown at an alarming rate and now stands at around 8 billion. Typically, outbreaks cause significant negative impacts on the environment and other species.
We need to recognize that epidemics not only reflect what is happening to us but also what we are doing to the environment.