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Why so many epidemics are occurring in Asia and Africa, and why more can be expected
On February 18, 2020, in Seoul, South Korea, people wearing face masks passed an electric screen warning about COVID-19. Coronavirus disease, known as AP Photo / Ann Young-joon COVID-19, is a horrifying reminiscent of the imminent global threat posed by emerging infectious diseases. Epidemics have occurred throughout human history, but now seem to be increasing. Over the last two decades, coronavirus alone has caused three outbreaks worldwide. To make matters worse, the period between these three pandemics is getting shorter. I am a virologist and deputy director of the Institute of Animal Diagnosis, Pennsylvania State University. At my laboratory, I am studying a zoonotic virus that jumps out of animals and infects humans. Most pandemics have at least one thing in common. It has begun a deadly activity in Asia or Africa. Why it might surprise you. Face mask shoppers line up in Wuhan’s grocery stores in 11 million cities in Hubei Province, central China. Urbanization of once jungle areas of Asia and Africa has contributed to the spread of these deadly viruses. AP Photo / Arek Rataj Population Explosion and Changes in Urban Landscapes Unprecedented changes in population are one of the reasons for the outbreak of more diseases in Asia and Africa. Rapid urbanization is occurring throughout Asia and the Pacific, where 60% of the world already lives. According to the World Bank, in the first decade of the 21st century, about 200 million people moved to urban areas in East Asia. Looking at it, 200 million people could form the eighth most populous country in the world. Migration on that scale means that forest areas will be destroyed and residential areas will be created. Wild animals forced to approach cities and towns inevitably encounter livestock and population. Wild animals often carry the virus. For example, bats can carry hundreds. The virus can then jump from species to species and eventually infect people. Ultimately, extreme urbanization creates a vicious cycle. More people will result in more deforestation, and human expansion and habitat loss will ultimately kill predators, including those that feed on rodents. When there are no predators, or at least the number drops sharply, the rodent population grows explosively. And so is the risk of zoonotic diseases, as studies in Africa show. The situation can get worse. Most of East Asia’s population still lives in rural areas. Urbanization is expected to continue for decades. A family-owned farm in Zambia. Livestock diseases are common and are an easy way for pathogens to pass from animals to humans. Getty Images / Gillem Sartrio / AFP Subsistence Agriculture and Animal Markets Host biodiversity tropical regions already have large pools of pathogens, greatly increasing the likelihood of new pathogens emerging. I will. Agricultural systems throughout Africa and Asia are useless. On both continents, many families rely on subsistence agriculture and a very small supply of livestock. Disease control, feeding and breeding of these animals are very limited. Cattle, chickens and pigs that can suffer from endemic are often in close contact with a variety of non-livestock and humans. And the live animal market, which is common not only on farms, but throughout Asia and Africa, is characterized by crowded conditions and an intimate mix of multiple species, including humans. This also plays an important role in how killer pathogens emerge and spread between species. Another risk: Bushmeat hunting and slaughter. This is especially widespread in sub-Saharan Africa. These activities connect people with wildlife because they threaten animal species and irreparably change ecosystems. Bushmeat hunting is a clear and major path for the transmission of zoonotic diseases. So are traditional herbal medicines that aim to provide treatments for many symptoms such as arthritis, epilepsy, and erectile dysfunction. There is no scientific evidence to support most of the claims, but Asia is a huge consumer of traditional herbal medicine products. Tigers, bears, rhinos, scales, and other animal species are poached, so these suspicious drugs can be mixed with parts of the body. This also contributes significantly to the increased interaction between animals and humans. In addition, demand may increase as online marketing surges with the constant economic growth of Asia. Only a matter of time Thousands of viruses continue to evolve. It’s only a matter of time before another outbreak occurs in this part of the world. All coronaviruses that caused the recent epidemic, including COVID-19, jumped from bats to other animals before infecting humans. It is difficult to predict exactly which sequence of events will cause a pandemic, but there is one thing that is certain. These risks can be mitigated by developing strategies that minimize the human impact that contributes to ecosystem disruption. As current outbreaks show, infectious diseases that occur in parts of the world can spread virtually quickly around the world. There is an urgent need for constructive conservation strategies to prevent deforestation and reduce animal-human interactions. And a comprehensive global surveillance system for monitoring the emergence of these diseases will be an essential tool in combating these deadly and horrific epidemics. [Deep knowledge, daily. Sign up for The Conversation’s newsletter.]This article has been republished by The Conversation, a non-profit news site aimed at sharing ideas from academic experts. Written by Pennsylvania State University Thresh V. Kuchipudi. Read more: The quest for coronavirus treatment shows how science can change for the better What scientists are doing to develop new coronavirus vaccines Coronavirus: The next virus outbreak Preparations should begin Suresh V Kuchipudi is funded by the United States Department of Agriculture (USDA)