Virus most likely came from Asian bat
The origin of COVID-19 has been globally disputed and fervently questioned, however the Chinese horseshoe bat has once again been cast into the spotlight, new research suggests.
The common species of bats are found across China, as well as Sub-Saharan African and Southeast Asian countries like Nepal, Vietnam and India. They are both hunted for food and used in traditional medicine.
A study conducted by the microbiology department of the University of Hong Kong suggested the horseshoe bat may be the "original host" of the virus, however more research is needed to confirm this.
During the study, researchers created a group of cells identical to the Chinese horseshoe bats and then reinfected the cell structure with the coronavirus. The experiment showed the cells were "fully susceptible to SARS-CoV-2 infection" and could "sustain robust viral replication".
While many of the symptoms of coronavirus are linked to respiratory issues like a dry cough, sore throat and difficulty breathing, the study also looked at why some patients experience "enteric" symptoms like diarrhoea. Through this it concluded that replication of COVID-19 in intestinal cells suggested "human intestinal tract might be a transmission route of SARS-CoV-2" too.
To date there have been several theories of where the virus originated and how it was transferred to humans. While there's no conclusive theory, some scientists believe the infection began in a bat, before it was potentially transferred to human by a snake, cat or pangolin.
Some have also posited that the virus was born in a lab. US Secretary of State Mike Pompeo alleged the disease was manufactured in a laboratory in Wuhan, with the Chinese government denying these claims.
The deputy director of the Chinese Ministry of Foreign Affairs Information Department, Lijian Zhao has also shared an article on his Twitter which suggests the virus originated in the US. The article however had been published by a think tank previously accused of promoting conspiracy theories.
This article is very much important to each and every one of us. Please read and retweet it. COVID-19: Further Evidence that the Virus Originated in the US. https://t.co/LPanIo40MR— Lijian Zhao 赵立坚 (@zlj517) March 13, 2020
Like the current pandemic, the origin of the 2003 SARS outbreak was also linked to a population of horseshoe bats in China's Yunan province. While the exact genetic sequencing has never been found in a bat, scientists have sequenced the genomes of 15 viral strains and found they contained all the genetic pieces that make up the human version when taken together.
Speaking to Nature research journal in 2017, a virologist at the University of Hong Kong who co-discovered the SARS virus, Kwok-Yung Yuen warned against markets selling animals in a bid to prevent future outbreaks.
"It reinforces the notion that we should not disturb wildlife habitats and never put wild animals into markets," he said.
"(It's) the way to stay away from the harm of emerging infections."