Chinese scientific research team: New crown virus has been mutated, there are 2 subtypes, and the infectivity is different

In the dissertation, by analyzing the largest genome evolution of 103 new crown virus viruses, it was found that 149 mutations have occurred in the virus strains, and most of them have been generated recently. The study revealed that the new crown virus has evolved into two subtypes, L and S.

Has the new crown virus been mutated? How to mutate? This is one of the focuses of current academic research. The latest findings of the Chinese scientific research team show that the new crown virus has recently generated 149 mutation points and has evolved into two subtypes, namely the L subtype and the S subtype. The study found that the two subtypes showed significant differences in geographical distribution and population proportions. The S type is a relatively older version, while the L subtype is more aggressive and more contagious. An in-depth understanding of different subtypes will help differentiated treatment and prevention of new coronary pneumonia. The above research comes from the paper "On the origin and continuing evolution of SARS-CoV-" 2). Corresponding authors of the thesis are: Researcher Lu Jian (Bioinformatics Center, School of Life Sciences, Peking University), and Researcher Cui Jie (Shanghai Pasteur Institute of Chinese Academy of Sciences). In the dissertation, by analyzing the largest genome evolution of 103 new crown virus viruses, it was found that 149 mutations have occurred in the virus strains, and most of them have been generated recently. The study revealed that the new crown virus has evolved into two subtypes, L and S. Of these, 101 belong to these two subtypes. In terms of proportion, the L subtype reached 70% and the S subtype accounted for 30%. The author of the paper believes that, based on the evolution of the new coronavirus, there may be a large difference in the transmission ability and severity of disease of the L and S subtypes.  The paper states that the difference between the two subtypes is at the 28144 position of the viral RNA genome. The L subtype is the T base (corresponding to leucine, Leu), and the S subtype is the C base (corresponding to serine, Ser). By comparing with other coronaviruses, the authors found that the S-type new coronavirus is closer to the bat-derived coronavirus on the phylogenetic tree, and concluded that the S-type is relatively older.

https://view.inews.qq.com/a/20200304A0ERIU00?uid&chlid=news_news_subnews&fbclid=IwAR24Gi3-LZhc_mto0FCljaJp7mK5X8H59OkaFsYZ2aHZCwB2neoV5vqYQ7g 

Bet a cup of coffee that the Brazilian version, is Italian, and that in turn is from Iran.

My take on it is, if they saying CFR of 4 they mean 

7/8

MERS was 8

A similar article is in the Times today. It states that the S strain is the milder one and makes up 30% of all cases, it was an early form of the disease. Then it mutated into the L strain which is far more aggressive and is responsible for 70% of all cases. The L strain is easier to spot because the symptoms are more severe. It is quite easy for the milder S strain to be undiagnosed due to the milder / less obvious symptoms. 

Here's a link

https://www.thetimes.co.uk/edition/news/coronavirus-has-an-aggressive-and-a-milder-strain-scientists-find-qfmfsl9jf

Coronavirus has mutated into a more aggressive strain, scientists find

Scientists have identified two strains of the novel coronavirus causing infections, one more aggressive than the other, indicating that the disease has mutated at least once.

In a new study published as Britain was told to expect a pandemic, Chinese researchers suggest that after Covid-19 crossed into humans, the original strain evolved into a new type and both of these are now circulating.

Although further research is needed, the preliminary study, carried out at Peking University’s school of life sciences and the Institut Pasteur of Shanghai, sheds some light on how the disease is evolving.

The researchers identified two strains, with the more aggressive accounting for 70 per cent of those they analysed and a less aggressive strain making up the rest.

The less aggressive strain, identified as ‘S’ appeared to be the ancestor of the more aggressive one, ‘L’.

Strain ‘L’ was found to be more prevalent at the start of the original outbreak in Wuhan but began to subside in early January. The S type has since become more common.

The study, published in the journal of the Chinese Academy of Sciences National Science Review, suggests this could be due to the rush to treat patients infected with the L strain, whose symptoms are easier to detect.

“If the L type is more aggressive than the S type, why did the relative frequency of the L type decrease compared to the S type in other places after the initial breakout in Wuhan?” the researchers asked. “One possible explanation is that, since January 2020, the Chinese central and local governments have taken rapid and comprehensive prevention and control measures.

“Human intervention may have placed more severe selective pressure” on the aggressive strain, the researchers wrote, while the less aggressive strain “might have increased in relative frequency due to relatively weaker selective pressure”.

The scientists said that due to the small sample size more research is needed. “These findings strongly support an urgent need for further immediate, comprehensive studies that combine genomic data, epidemiological data and chart records of the clinical symptoms of patients with coronavirus disease 2019,” the authors wrote.

Experts not directly involved in the study said its findings were interesting but cautioned against drawing firm conclusions from such preliminary research.

“It’s difficult to confirm studies like this without a direct side-by-side comparison of pathogenicity and spread in, ideally, an animal model, or at least a greatly extended epidemiological study,” said Stephen Griffin, a professor and expert in infection and immunity at Leeds University.

News of the apparent mutation was the second-highest trending topic on the Chinese social media site Weibo today and was shared by Chinese state media.

Today one of China’s top medical associations said that the median incubation period of the coronavirus is five to seven days and the maximum 14 days.

The remarks by Du Bin, chairman of the critical care medical branch of the Chinese Medical Association, are the most conclusive assessment of the virus’s incubation period by a government-affiliated medical organisation to date, Retuers reports.

New coronavirus cases in China have begun to fall following strict restrictions, including transport suspensions and the extension of the lunar new year holiday.

Agreed

I've said the last few weeks we could be dealing with a mutation in Iran.  I fully understood the arguments with reporting issues, but the mutation could not be ruled out.   Now apparently we are dealing with more than one strain / variant.  

I saw a Harvard researcher said about 70 percent of the US population could get the virus. Of the 70 percent, if 3.4 percent die...that is approximately  7.8 million deaths in the US. Not a slate wiper at that rate, but it would be life changing for most I am guessing.

Mutations are an unknown, could get more lethal or less.

QP

Aggressive strain prevalent in Wuhan

https://www.caixinglobal.com/2020-03-08/head-more-aggressive-covid-19-strain-more-prevalent-in-wuhan-study-101525471.html

Maybe XiJingping didn't smother it all, Italy with a 4 1/4 % CFR,Iran don't look much better.