BEIJING, March 30 (Xinhua) -- Science and technology, which have led China onto a new development path driven by innovation, are also playing a pivotal role in preventing the spread of virus and saving lives amid the novel coronavirus disease (COVID-19) outbreak.
The country has been pooling scientific wisdom to improve the knowledge about the virus, upgrade diagnosis and treatment plans as well as develop vaccines as fast as possible.
"Science and technology are the most powerful weapon in humanity's battle against diseases," Chinese President Xi Jinping said.
RESEARCH IMPROVES KNOWLEDGE
Chinese researchers are racing against time. Their early work of isolating the novel coronavirus and sequencing its whole genome has enabled scientists and health authorities worldwide to carry out follow-up research.
To collect samples from patients and obtain the virus, it was not only necessary to isolate the virus, but to enable it to passage -- or propagate -- stably, said Ren Lili, a researcher with the Institute of Pathogen Biology, Chinese Academy of Medical Sciences.
By Jan. 26, her institute had provided the genome sequences of five novel coronavirus strains to the National Genomics Data Center (NGDC).
Repeated freezing and thawing of the samples during the transportation makes it difficult for the virus to proliferate. "We must operate in the third level of biosafety with inclined tubes specially used to reduce the inoculation amount and single tubes to avoid cross-infection," Ren said.
Her team's rigorous and diligent work has helped lay a foundation for the development of testing kits, drug screening and vaccine evaluation.
Chinese researchers have also dug into the virus source, its transmission routes and the patients' clinical features to offer references for the COVID-19 prevention, control and treatment.
By analyzing genome samples of wild animals, they discovered that COVID-19 may originate in bats, and pangolins are the most likely intermediate host of the virus.
They also indicated that the virus may spread through drainage systems, except for the conventional transmission by respiratory droplets and direct contact, after isolating a virus strain from a patient's feces.
Chinese pathologists released the results of autopsies on 11 patients who died of COVID-19 to help understand better how the new infectious disease affects visceral organs, and a study based on the data of 1,099 laboratory-confirmed patients across China warned that the infected may have no fever or CT abnormality.
By March 26, Chinese researchers had published 54 research papers on prestigious international journals, and a platform for COVID-19 research sharing went online on Chinese Medical Journal Network with more than 700 research papers recording 2.3 million views.
SEARCH FOR EFFECTIVE TREATMENT
Chinese researchers have kept searching for more effective drugs and exploring new treatment methods to prevent patients with mild symptoms from getting worse and save severe patients.
They scanned more than 70,000 drugs or compounds through computer simulations and in vitro enzyme activity tests and selected 5,000 potentially effective drug candidates.
Then they were tested at the cellular level against the common coronavirus infection, and about 100 drugs were chosen for further experiments, which helped to select the final drugs for clinical trials, according to the Ministry of Science and Technology.
Drugs including Favipiravir, Chloroquine Phosphate, Tocilizumab and Remdesivir and traditional Chinese medicine have been found to have the potential to defeat COVID-19. Some of them have completed clinical trials in China.
Favipiravir, an influenza drug that was approved for clinical use in Japan in 2014, has made patients turn negative for the virus in a shorter time and shown no noticeable adverse reactions in a concluded clinical trial in Shenzhen, south China's Guangdong Province.
Tocilizumab, with the common brand name Actemra, has been found effective in blocking the inducement of the inflammatory storm and included in China's latest version of diagnosis and treatment guidelines on COVID-19.
China is also pushing forward the utilization of some advanced technologies such as stem cell and artificial liver and blood purification in the treatment of severe cases.
The stem cell therapy has been used to treat 64 patients in severe and critical conditions, proving effective in reducing severe inflammatory reactions caused by COVID-19, as well as reducing lung injury and pulmonary fibrosis in patients.
DEVELOP VACCINES IN FIVE APPROACHES
China has adopted five technological approaches to develop COVID-19 vaccines, namely inactivated vaccines, genetic engineering subunit vaccines, adenovirus vector vaccines, nucleic acid vaccines, and vaccines using attenuated influenza virus as vectors. Most teams are expected to complete preclinical research in April.
The recombinant vaccine developed by the Institute of Military Medicine under the Academy of Military Sciences started its clinical trial on March 16. Chen Wei, the leader of the team, said that they strive to put the vaccine into clinical application in the shortest time, to provide strong scientific and technological support for winning this battle against the epidemic.
The biotech company Stemirna Therapeutics has launched a program with the Shanghai East Hospital of Tongji University to develop an mRNA vaccine, which has the advantage of a shorter development and production cycle. The mRNA vaccine for COVID-19 is expected to enter clinical trials in mid-April.
Zhang Linqi, from Tsinghua University, is leading a team to try a genetic engineering method for the design of vaccines.
By studying the mechanism of the virus's invasion into host cells at the atomic level, Zhang's team hopes to provide a better understanding of viral infection mechanisms and unveil a more precise and focused target for vaccine development.
As the vaccines have to be tested first on animals, Chinese researchers have quickly established humanized transgenic mouse models and Rhesus monkey models. Currently, eight COVID-19 vaccines are under evaluation with the animal model.
Chinese officials and experts have also highlighted the need to respect scientific principles and strictly follow standards to ensure the safety and quality of the vaccine.