Wuhan coronavirus outbreak: 6 out of 10 infectious diseases that affect people come from animals, claims report
While scientists are still trying to figure out how the Wuhan coronavirus jumped from animals to humans, and from which animal, experts reveal that more than half — six out of every 10 infectious diseases in people — spread from animals.
According to a report, the zoonotic diseases of most concerns in the US are emerging coronaviruses (for example, severe acute respiratory syndrome or SARS and Middle East respiratory syndrome or MERS), zoonotic influenza, salmonellosis, West Nile virus, plague, rabies, brucellosis, and Lyme disease.
It is a joint report by the US Centers for Disease Control and Prevention (CDC), US Department of the Interior (DOI), and US Department of Agriculture (USDA). The selection was made based on the potential of the disease to cause a pandemic and epidemic, as well as the severity of the disease.
Zoonotic diseases are illnesses that can spread between animals and people. Approximately 60% of infectious diseases in humans are zoonotic, and about 70% of emerging infections in humans are zoonotic.
The CDC report emphasizes that since six out of every 10 infectious diseases in people are zoonotic, it crucial that the nation strengthens its capabilities to prevent and respond to these diseases using a one health approach.
"Every year, tens of thousands of Americans get sick from diseases spread between animals and people. CDC’s One Health Office is collaborating with DOI, USDA, and other partners across the government to bring together disease detectives, laboratorians, physicians, and veterinarians to prevent those illnesses and protect the health of people, animals, and our environment," says Dr. Casey Barton Behravesh, director, One Health Office, CDC, in the analysis.
According to the World Health Organization (WHO), detailed investigations found that SARS-CoV was transmitted from civet cats to humans and MERS-CoV from dromedary camels to humans. "Coronaviruses are zoonotic. Several known coronaviruses are circulating in animals that have not yet infected humans," says WHO.
The 2019 Novel Coronavirus (2019-nCoV) is also zoonotic, which implies that the virus jumped from animals to humans. Scientists have been trying to figure out the source of the infection. The virus has killed 132 so far.
At this stage, it is suspected that the outbreak originated from Wuhan's local seafood market where bats and snakes were being sold until recently, but experts are divided over this. The initial victims of the virus were a group of people who had either worked or visited the market. The market has been closed since January 1, 2020.
Chinese authorities have also temporarily banned the trade of wild animals following a viral outbreak in Wuhan, saying they will "severely investigate and punish" violators.
According to an analysis in The Conversation, viruses are "prolific" at adapting to new environments and infecting new hosts. As a result, they can jump the species divide from animals to humans – as the new coronavirus in China is showing.
"Seven human coronaviruses (HCoVs) have been identified to date: two in the 1960s, and five since SARS in 2003. It is the seventh that is now making headlines," says Burtram Fielding, Director, Research Development and Principal Investigator, Molecular Biology and Virology Research Laboratory Department of Medical BioSciences, University of the Western Cape.
He says in the analysis: "As with other coronaviruses, 2019-nCoV is zoonotic in origin. While it’s too early to confirm, it appears that 2019-CoV is what’s known as a recombinant virus. This means it bears the genetic material of both bats and snakes, suggesting that the virus jumped from bats to snakes in the wild, and then, of course, to humans."
The study cautions that as the human population expands and populates new geographical regions, often at the expense of wildlife, the possibility that humans will come into close contact with animal species that are potential hosts of an infectious agent increases.
"The threat of future pandemics is real as highly pathogenic coronaviruses continue to spill over from animal sources into the human population," says the study.