Stephen Chen

Recovered Covid-19 patients in China may still be vulnerable to a mutant form of the pathogen spreading overseas, a new study says. Professor Huang Ailong from Chongqing Medical University said there is an urgent need to determine what threat the mutation, known as D614G, poses to people who have recovered from a different form of the virus. D614G began spreading in Europe in early February. By May, it was the dominant strain around the world, having been found in 70% of sequenced samples in Europe and North America. Antibodies found in patients who had been infected with earlier forms of the pathogen failed to neutralize the mutant strain, the scientists said in a paper published on Biorxi

A volcano in northeast China could be “recharging” for an eruption, with a vast amount of magma believed to be rising up underneath it, according to a team of geophysicists. The researchers say they discovered two huge magma chambers under Wei Mountain in Heilongjiang, near the border with Russia and North Korea. Their modeling suggests the chambers dwarf the volcano, which is 328 feet tall and 3 miles wide. It was a surprise discovery, since the volcano last erupted more than 500,000 years ago and was considered extinct. Geologists have been more focused on Changbai Mountain (known in North Korea as Mount Paektu), to the south, whose eruption in 946AD was one of the most powerful volcanic e

Doctors in New York have reported a rare set of symptoms in a coronavirus patient – a case so puzzling that the medical team could not confirm the man had Covid-19 until just before he was discharged from hospital. In a study published in the medical journal The Lancet on Monday, the doctors said scans of the patient’s lungs indicated a fungal invasion, tests showed no telltale sign of the coronavirus in the upper respiratory tract and the patient had an immune response called a cytokine storm within just hours of the disease’s onset. “For a disease that was unknown only five months ago, it might … be too early for clinicians to be certain of which manifestations are typical,” the team led b

Scientists have created a fully synthesized strain of the coronavirus with brewer’s yeast, according to a new study from Europe. The development will help give health authorities and diagnostic laboratories access to the virus without needing clinical samples, said the researchers, led by Joerg Jores and Volker Thiel from the University of Bern in Switzerland, in a paper published in Nature on Monday. Experts said the man-made strain would help researchers conduct real-world experiments to find cures and improve preventive measures. However, a common problem of using artificial viruses is that their mutations may run wild and render the experiments meaningless. But the new strain, dubbed rS

The coronavirus outbreak in France was not caused by cases imported from China, according to a new study by scientists at the Institut Pasteur in Paris. Genetic analysis showed that the dominant types of viral strains in France belonged to a clade – or group with a common ancestor – that did not come from China or Italy, Europe’s earliest epicenter. Instead, the outbreak was caused by a locally circulating strain of unknown origin, the researchers said. The research was led by virologists Dr Sylvie van der Werf and Etienne Simon-Loriere. It was released on bioRxiv.org last week and has not been peer-reviewed. The findings highlight the difficulties governments face in tracing the source of

A new study by one of China’s top scientists has found the ability of the new coronavirus to mutate has been vastly underestimated, and different strains may account for different impacts of the disease in various parts of the world. Professor Li Lanjuan and her colleagues from Zhejiang University found many mutations not previously reported within a small pool of patients.  They also confirmed, for the first time using laboratory evidence, that certain mutations could create strains of the coronavirus, officially Sars-CoV-2, deadlier than others. “Sars-CoV-2 has acquired mutations capable of substantially changing its pathogenicity,” Li and her collaborators wrote in a paper released on pr

The first outbreak of the coronavirus could have happened as early as September and further south in China than previously thought, according to a team of scientists led by the University of Cambridge. Researchers investigating the virus’s origin analyzed a large number of strains from around the world and calculated that the initial outbreak occurred in a window between September 13 and December 7. Some early signs of the virus also prompted the scientists to cast doubt on the idea that the coronavirus originated in the central Chinese city of Wuhan, where it first emerged.  “The virus may have mutated into its final ‘human-efficient’ form months ago, but stayed inside a bat or other animal

The coronavirus that causes Covid-19 may be able to kill the powerful immune cells that are supposed to kill the virus, scientists have warned.  The surprise discovery, made by a team of researchers from Shanghai and New York, coincided with front-line doctors’ observation some patients of Covid-19 had a severely weakened immune system similar to that found in people infected with HIV. Lu Lu, from Fudan University in Shanghai, and Jang Shibo, from the New York Blood Center, made the discovery by joining the living virus, officially named Sars-CoV-2, to the cell lines of laboratory-grown T lymphocytes. T lymphocytes, also known as T cells, play a central role in identifying and eliminating al

The coronavirus that causes Covid-19 might have been quietly spreading among humans for years or even decades before the sudden outbreak that sparked a global health crisis, according to an investigation by some of the world’s top virus researchers. Researchers from the United States, Britain and Australia looked at piles of data released by scientists around the world for clues about the virus’s evolutionary past, and found it might have made the jump from animal to humans long before the first detection in the central China city of Wuhan. Though there could be other possibilities, the scientists said the coronavirus carried a unique mutation that was not found in suspected animal hosts, bu

The new coronavirus is more sensitive to alcohol than Sars or Mers and can be killed almost completely by ethanol concentrations as low as 30%, according to a joint study by scientists from Germany and Switzerland. Though many spirits such as whisky or gin have an alcohol content higher than that, scientists do not recommend using them as a disinfectant unless in desperate situations – and they stressed that people should not regard drinking as a way to prevent or cure Covid-19, the disease caused by the coronavirus. Stephanie Pfaender, the lead scientist of the study, said on Wednesday that their experiment was conducted in a laboratory setting, therefore “one cannot directly translate thes