A recent research by Cambridge University found three different strains of the virus in different parts of the world. As COVID-19 continues to sweep across the world, one of the main concerns is whether the virus has since mutated. We asked experts:
“Has COVID-19 mutated?”
Dr Tee Kok Keng, Head of the Pathogen Genetics & Evolution Laboratory in University of Malaya, said:
“The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, is a new virus that belongs to the family Coronaviridae that normally circulate in animals and humans. Like any other viruses, SARS-CoV-2 will continue to mutate while circulating in humans. Such mutations, however, are usually minor and take a long time to accumulate. In the past four months since the outbreak has started, the virus has been spreading in many countries and genetic analysis of the virus sampled across the world has shown some degree of minor mutations that are specific to certain geographical regions.
These mutations are most likely non-alarming, but serve as a “signature” that help epidemiologists to track the movement (gene flow) of the virus. So, not all mutations are bad, per se. However, if certain mutations occur to some important proteins of the virus, either through a random event or positive selection, these mutations may change the “phenotype” or characteristics of the virus.
Such mutants may be causing more severe disease (increased virulence), more transmissible (increased virus fitness), more resistant to the human immune response (escape mutants), or simply non-detectable by the conventional diagnostic assay that was designed based on the non-mutated (wild type) strain. However, such events are yet to occur at this point. Therefore, continuous genetic surveillance and mass sequencing are essential to trace the distribution and dispersion of the virus.”
Dr Jasmine Khairat, Virologist & Senior Lecturer at Institute of Biological Sciences, Faculty of Science in University of Malaya, said:
“In every viral replication cycle, a virus will naturally mutate due to its efficient but flawed replication mechanism. However, with that being said, this will not hamper the development of current vaccines as there are multiple vaccination strategies being worked on to overcome this issue from inactivated virus, subunit proteins, messenger RNA and so on.”
Dr Ng Siew Kit, Biochemist & Senior Lecturer at the Advanced Medical and Dental Institute, Universiti Sains Malaysia, said:
“Vaccination aims to train our immune system to recognise SARS-CoV-2 virus and mount a rapid response during infection. Conventional vaccines involve using weakened virus (flu vaccines) or virus-like particles containing virus surface proteins (Hepatitis B vaccines). The emphasis on virus surface proteins is because those are normally what our immune cells encounter.
Now if the mutation rate of these surface proteins are very high, vaccines may only provide short term protection (but still valuable to protect frontliners in the event of outbreaks); conversely if the mutation rate is low, we are more likely to be able to come up with effective vaccines providing long term protection.”
Dr Tan Cheng Siang, Virologist & Head of Centre for Tropical and Emerging Diseases, Faculty of Medicine and Health Sciences, University Malaysia Sarawak, said:
“No RNA viruses stay the same forever. The virus progeny from every generation tends to differ slightly in its genomic sequence due to its high mutation rate. The vaccine based on the older virus strain may not prevent an infection, but I believe it will offer protection against developing severe disease.”
|Disclaimer: Science Media Centre Malaysia has collected these comments to provide journalists with a range of expert perspectives on the subject. The views expressed here are personal opinions of the experts. They do not in any way reflect the views of the Science Media Centre or any other organization unless specifically stated.|
Bionotes of experts
Dr Jasmine Khairat received her PhD and virology training from Monash University Malaysia. Currently, she is a senior lecturer at Institute of Biological Sciences (ISB) Faculty of Science in the University of Malaya, Kuala Lumpur, Malaysia and has been teaching Microbiology courses. Her researches include host-pathogen interactions, virus surveillance, emerging infectious diseases and antiviral studies involving respiratory viruses specifically influenza virus to improve our knowledge in viral pathogenesis.
Dr Ng Siew Kit is a senior lecturer in Advanced Medical and Dental Institute, Universiti Sains Malaysia (AMDI, USM). He received his undergraduate education and Ph.D. training in Biochemistry at University of Cambridge, UK. He is a principal investigator within the RNA-Bio Research Group at AMDI, USM. His main research interest is on antiviral innate immunity. In particular, he works on virus detection and signaling pathways during viral infections, as well as regulatory mechanisms of the subsequent type I interferon response.
Dr Tan Cheng Siang is the Head of Centre for Tropical and Emerging Diseases, Faculty of Medicine and Health Sciences, University Malaysia Sarawak. A trained virologist, he has more than 20 years experience in handling infectious viruses, virus isolation and identification, phylogeny, molecular epidemiology, recombinant protein expression and diagnostic tool development. He is also a certified biosafety officer and holds four Certified Professional credentials from the International Federation of Biosafety Associations (IFBA).
Dr Tee Kok Keng is a Senior Lecturer in the Faculty of Medicine and the head of the Pathogen Genetics & Evolution Laboratory in University of Malaya (UM). He is an adjunct Associate Professor at the School of Healthcare and Medical Sciences, Sunway University. His research interest focuses on the genetic and evolutionary characterization of blood-borne and respiratory viruses (including human coronaviruses). He has published over 90 peer-reviewed articles (h-index 22). He is currently the Editor for various international journals including PLoS One, Frontiers in Microbiology, and Virology Journal. He is the recipient of the 2017 UM Outstanding Young Researcher.
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