What do we know about new strains of this virus that is more infectious than the first strains?
What do we know about new strains of this virus that is more infectious than the first strains?
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Scientists are working to better understand the new variants (or versions) of the COVID-19 virus, how they spread, if vaccines will be effective, if the new variants are detectable by viral tests, and whether the variants cause mild or severe disease. Information about new variants of COVID-19 is changing quickly. According to the US Centers for Disease Control and Prevention, there is no evidence that the new COVID-19 variants cause more severe illness or increased risk of death. However, there is some evidence that suggests that one mutation (D614G) may spread more quickly than other variants. Viruses constantly change as they reproduce in order to keep spreading into more cells. These changes are called "viral mutations." Mutations create a new, updated version of the virus, which we call a "strain" or "variant" (though other similar words include "lineage" and "mutant"). These variants may have different properties than previous versions of the virus and may allow the virus to infect more people or may cause more severe illness. Many variants of COVID-19 have been documented globally, and scientists are continuing to monitor the virus as it changes and spreads around the world. To prevent the spread of COVID-19, international health agencies and the public health community continue to encourage the everyone to wear face masks (the U.S. Centers for Disease Control and Prevention now recommend wearing a cloth mask over a surgical mask or individual KN95/N95 masks), practice social distancing (maintaining 6 feet/2 meters physical distance), avoid crowds especially in indoor areas, and practice frequent hand washing with soap and warm water.
Scientists are working to better understand the new variants (or versions) of the COVID-19 virus, how they spread, if vaccines will be effective, if the new variants are detectable by viral tests, and whether the variants cause mild or severe disease. Information about new variants of COVID-19 is changing quickly. According to the US Centers for Disease Control and Prevention, there is no evidence that the new COVID-19 variants cause more severe illness or increased risk of death. However, there is some evidence that suggests that one mutation (D614G) may spread more quickly than other variants. Viruses constantly change as they reproduce in order to keep spreading into more cells. These changes are called "viral mutations." Mutations create a new, updated version of the virus, which we call a "strain" or "variant" (though other similar words include "lineage" and "mutant"). These variants may have different properties than previous versions of the virus and may allow the virus to infect more people or may cause more severe illness. Many variants of COVID-19 have been documented globally, and scientists are continuing to monitor the virus as it changes and spreads around the world. To prevent the spread of COVID-19, international health agencies and the public health community continue to encourage the everyone to wear face masks (the U.S. Centers for Disease Control and Prevention now recommend wearing a cloth mask over a surgical mask or individual KN95/N95 masks), practice social distancing (maintaining 6 feet/2 meters physical distance), avoid crowds especially in indoor areas, and practice frequent hand washing with soap and warm water.
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What our experts say
Scientists are working to better understand the new variants (or versions) of the COVID-19 virus, how they spread, if vaccines will be effective, if the new variants are detectable by viral tests, and whether the variants cause mild or severe disease. Information about new variants of COVID-19 is changing quickly. According to the US Centers for Disease Control and Prevention, there is no evidence that the new COVID-19 variants cause more severe illness or increased risk of death. However, there is some evidence that suggests that one mutation (D614G) may spread more quickly than other variants.
Viruses constantly change as they reproduce in order to keep spreading into more cells. These changes are called "viral mutations." Mutations create a new, updated version of the virus, which we call a "strain" or "variant" (though other similar words include "lineage" and "mutant"). These variants may have different properties than previous versions of the virus and may allow the virus to infect more people or may cause more severe illness. Many variants of COVID-19 have been documented globally, and scientists are continuing to monitor the virus as it changes and spreads around the world.
To prevent the spread of COVID-19, international health agencies and the public health community continue to encourage the everyone to wear face masks (the U.S. Centers for Disease Control and Prevention now recommend wearing a cloth mask over a surgical mask or individual KN95/N95 masks), practice social distancing (maintaining 6 feet/2 meters physical distance), avoid crowds especially in indoor areas, and practice frequent hand washing with soap and warm water.
Scientists are working to better understand the new variants (or versions) of the COVID-19 virus, how they spread, if vaccines will be effective, if the new variants are detectable by viral tests, and whether the variants cause mild or severe disease. Information about new variants of COVID-19 is changing quickly. According to the US Centers for Disease Control and Prevention, there is no evidence that the new COVID-19 variants cause more severe illness or increased risk of death. However, there is some evidence that suggests that one mutation (D614G) may spread more quickly than other variants.
Viruses constantly change as they reproduce in order to keep spreading into more cells. These changes are called "viral mutations." Mutations create a new, updated version of the virus, which we call a "strain" or "variant" (though other similar words include "lineage" and "mutant"). These variants may have different properties than previous versions of the virus and may allow the virus to infect more people or may cause more severe illness. Many variants of COVID-19 have been documented globally, and scientists are continuing to monitor the virus as it changes and spreads around the world.
To prevent the spread of COVID-19, international health agencies and the public health community continue to encourage the everyone to wear face masks (the U.S. Centers for Disease Control and Prevention now recommend wearing a cloth mask over a surgical mask or individual KN95/N95 masks), practice social distancing (maintaining 6 feet/2 meters physical distance), avoid crowds especially in indoor areas, and practice frequent hand washing with soap and warm water.
Context and background
Research about the virus that causes COVID-19, the novel coronavirus SARS-CoV-2, is ongoing, and scientists and researchers are continuing to learn and understand how the virus spreads, how long it can live outside of host cells, and how it affects different people around the world. Another major area of interest is understanding how the virus mutates (or changes). Some viruses mutate as part of their life cycle, and sometimes these changes can impact humans by making the virus easier to spread or more likely to cause serious infection.
RNA viruses, such as influenza and measles, are more prone to mutations than DNA viruses, such as herpes and human papillomavirus. Coronaviruses are RNA viruses that generally mutate slower than influenza. Some forms of SARS-CoV-2 have mutated and now look different than the original version of it found in China. More research is needed to understand the implications of any mutations in SARS-CoV-2, the virus that causes COVID-19.
Research about the virus that causes COVID-19, the novel coronavirus SARS-CoV-2, is ongoing, and scientists and researchers are continuing to learn and understand how the virus spreads, how long it can live outside of host cells, and how it affects different people around the world. Another major area of interest is understanding how the virus mutates (or changes). Some viruses mutate as part of their life cycle, and sometimes these changes can impact humans by making the virus easier to spread or more likely to cause serious infection.
RNA viruses, such as influenza and measles, are more prone to mutations than DNA viruses, such as herpes and human papillomavirus. Coronaviruses are RNA viruses that generally mutate slower than influenza. Some forms of SARS-CoV-2 have mutated and now look different than the original version of it found in China. More research is needed to understand the implications of any mutations in SARS-CoV-2, the virus that causes COVID-19.
Resources
- No evidence for increased transmissibility from recurrent mutations in SARS-CoV-2 (Nature Communications)
- Tracking changes in SARS-CoV-2 Spike: evidence that D614G increases infectivity of the COVID-19 virus (Cell)
- The D614G mutation in the SARS-CoV-2 spike protein reduces S1 shedding and increases infectivity (bioRxiv)
- This coronavirus mutation has taken over the world. Scientists are trying to understand why. (Washington Post)
- Viral Mutation Rates (Journal of Virology)
- SARS-CoV-2 genomic variations associated with mortality rate of COVID-19 (Nature - Journal of Human Genetics)
- New COVID-19 Variants (US CDC)
- Emerging SARS-CoV-2 Variants (US CDC)
- Maximizing Fit for Cloth and Medical Procedure Masks to Improve Performance and Reduce SARS-CoV-2 Transmission and Exposure, 2021 (U.S. CDC)
- No evidence for increased transmissibility from recurrent mutations in SARS-CoV-2 (Nature Communications)
- Tracking changes in SARS-CoV-2 Spike: evidence that D614G increases infectivity of the COVID-19 virus (Cell)
- The D614G mutation in the SARS-CoV-2 spike protein reduces S1 shedding and increases infectivity (bioRxiv)
- This coronavirus mutation has taken over the world. Scientists are trying to understand why. (Washington Post)
- Viral Mutation Rates (Journal of Virology)
- SARS-CoV-2 genomic variations associated with mortality rate of COVID-19 (Nature - Journal of Human Genetics)
- New COVID-19 Variants (US CDC)
- Emerging SARS-CoV-2 Variants (US CDC)
- Maximizing Fit for Cloth and Medical Procedure Masks to Improve Performance and Reduce SARS-CoV-2 Transmission and Exposure, 2021 (U.S. CDC)
