The coronavirus may have originated from bats, but it is likely that another species has infected humans.
When the Covid-19 epidemic broke out in January, many researchers investigated the intermediate host for transmitting coronavirus to humans. On Feb 15, Wu Yuan Bin, head of the Department of Science and Technology for Social Development, China’s Ministry of Science and Technology, said the studies identified bats as the most likely species.
However, recently published findings suggest that pangolin may be a host for the virus from bat to human. In other words, the SARS-CoV-2 virus was present in the first bat, but through an intermediate host, pangolin was transmitted to humans.
Mysterious intermediate host
In an article in Conversation , the team at the University of Michigan says they have evidence to show that pangolin is an intermediate host. The researchers agree with the general opinion that SARS-CoV-2 virus first appeared in Chinese horseshoe bats. However, the possibility of direct transmission from this bat to humans is quite low.
In 2003, the SARS virus was also transmitted from bats to an intermediate host, the mongoose, before it was transmitted to humans. Another coronavirus, MERS-CoV, caused the MERS epidemic in 2012 and also spreads from bats to camels before spreading it to humans.
It is important to identify the intermediate host, knowing which species will help to limit sales, thereby reducing the likelihood of spreading the virus. Since the end of January, a team of Chinese researchers said the snake, including the Chinese scorpion and cobra, could be the direct host of the SARS-CoV-2 virus to humans.
However, this study is suspected because there has been no evidence that coronavirus can be transmitted from cold-blooded animals such as snakes to humans.
Conclusions on snakes are based on the assumption that the codons (the trio of transcription codes, the genetic code on the information RNA) of the virus and host spread must be identical. After comparing the genetic codes of eight animals at the Wuhan Seafood Market, the team determined that snakes are the most similar genetic code to SARS-CoV-2.
However, the hypothesis of the above study has never been proven. The University of Michigan team compared the genetic code of the three coronavirus strains to about 10,000 animals, and found that the virus codon did not necessarily match the actual host.
The evidence shows that pangolin is the host
The group then went on to conduct a study on Malaysian pangolin (Manis javanica). They found that the genetic code taken from the coronavirus attached to the lung cells of this pangolin was 91% similar to SARS-CoV-2.
The protein spikes of these two viruses have only 5 distinct amino acids. Compared to the coronavirus from bat species, the protein spines of SARS-CoV-2 virus have 19 distinct amino acids. From this evidence, the team believes that pangolin is an animal most likely to spread the SARS-CoV-2 virus to humans.
This is not the first scientific study to conclude that the Malaysian pangolin. At the end of March, another research team at the University of Hong Kong also found a virus directly related to the SARS-CoV-2 virus in the Malaysian pangolin, seized from a wildlife transport line illegal in southern China.
“Detecting similarities of some strains of pangolin with SARS-CoV-2 virus suggests that the animal may be listed as an infectious host and need to be removed from animal markets. wild “, Dr. Tommy Lam, study author concludes in scientific report.
“Although pangolin is the most suspect species, our study concludes that we still need to consider other types of intermediate hosts. The coronavirus can be transmitted through many intermediate hosts before it is transmitted to humans. .
Several studies indicate that ferrets and cats can also be infected with SARS-CoV-2. We still don’t know if humans are likely to catch coronavirus from these animals, “a University of Michigan research team concluded.
- Every 15 seconds, 1 person dies of Covid-19 in the world
There are nearly 19 million Covid-19 infections worldwide and more than 700,000 deaths as of August 5. According to Reuters, one person dies every 15 seconds from the new strain of coronavirus.
The death of coronavirus infection surpassed 700,000 on August 5, according to Reuters statistics. The United States , Brazil, India and Mexico are countries with rapidly increasing deaths.
On average, nearly 5,900 people die every 24 hours from Covid-19, according to Reuters calculations based on data from the past two weeks.
This equates to 247 deaths every hour, or one person every 15 seconds from the new strain of coronavirus.
US President Donald Trump declared the Covid-19 pandemic to be controlled as far as possible in the US, where more than 155,000 people have died from the coronavirus. The response to the discrete pandemic in this country has not been able to prevent the number of infections from rising.
“They are dying, it’s true,” Trump said in an interview with news site Axios . “Accept this. But that doesn’t mean we haven’t done everything we can yet. The pandemic is under control as much as possible in America. This is a terrible epidemic.”
In Brazil, President Jair Bolsonaro ignores the severity of the pandemic and opposes restrictions to prevent virus spreading, even if he and some of his cabinet members are already virus-positive.
The pandemic affected Latin America, where about 640 million people live, more slowly than in other parts of the world. However, officials still struggle to control the virus because of the poverty and high population density of the area.
More than 100 million people across Latin America and the Caribbean live in slums, according to the United Nations Human Resources Program . Many worked in the informal economy, had little access to the welfare system, and had to work during the pandemic.
Even in places where the virus seems to have been prevented, the number of new infections has increased in recent times, signaling a long-lasting war.
Australia , Japan , Hong Kong , Bolivia, Sudan, Ethiopia, Bulgaria, Belgium, Uzbekistan and Israel all recorded a record increase in new infections over the past few days.
Australia also reported a record new death toll on August 5, bringing the total coronavirus deaths in the country to 247.
- The US surpass 5 million coronavirus infections
The US has recorded more than 5 million Covid-19 cases as of August 8. The United State also has more than 161,000 people died of coronavirus.
On 8/8, the number of coronavirus infections in the US surpassed the 5 million people, while American politicians are still debating about the pandemic bailout and schools considering whether to continue opening
With 5 million cases of Covid-19, the United States continues to be the country with the most cases in the world. Second is Brazil with about 3 million cases. India ranked third with 2 million positive cases.
In terms of cases per capita, the US ranks eighth in the world.
The number of US cases is reported by the New York Times based on reports of federal, state and local officials. Public health experts have warned that the actual number of people infected with coronavirus in the US is much larger.
The number of infections is on the rise in seven states, as well as in Puerto Rico, Guam and the US Virgin Islands, according to the New York Times. During the past week, Louisiana, Mississippi and Florida were the states with the most recent viral infections relative to the population.
The United States recorded its 1 million infection on April 28, more than three months after the first case was discovered in the country. As of June 10, the US exceeded 2 million cases. The US continues to hit the 3 million infection mark on July 7 and the 4 million cases on July 23.
The US is testing about 720,000 people a day, according to data from the Covid Tracking Project.
The number of new infections per day in the US peaked on July 16 with 75,697 cases. This number has gradually decreased and the average over the last seven days has been about 54,000 new infections per day.
At least 161,000 people have died since the pandemic started in the US.