Experts: More Variants after Omicron Likely
2022-01-26
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1Scientists warn that the fast-spreading Omicron will likely not be the last worrisome version of the coronavirus.
2The Omicron version of the coronavirus was first identified in mid-November.
3By the first week of January, the World Health Organization reported a record 15 million new COVID-19 cases.
4That is a 55 percent increase from the previous week.
5Every new infection provides a chance for the virus to mutate, or change.
6The fast spread of Omicron means the virus has more chances to develop new versions, called variants.
7Scientists do not know what the next variants will look like or how they might shape the pandemic.
8But they say there is no guarantee that new coronavirus variants will cause milder illness or that existing vaccines will work against them.
9And they urge wider vaccination now, while the shots still work against the virus.
10Dr. Leonardo Martinez is an infectious disease expert at Boston University.
11He said, "The faster Omicron spreads, the more opportunities there are for mutation, potentially leading to more variants."
12Research shows that Omicron is at least two times as contagious as the Delta variant and four times more contagious than the original version of the virus.
13Contagious means the variant could easily pass between people.
14Omicron is also more likely than Delta to reinfect individuals who previously had COVID-19 and to cause "breakthrough infections" - meaning to cause an infection even if a person is vaccinated.
15The variant's quick spread increases the chances that the virus will infect and remain inside people with weakened immune systems - giving it more time to develop mutations or changes.
16Dr. Stuart Campbell Ray of Johns Hopkins University said,
17"It's the longer...infections that seem to be the most likely breeding grounds for new variants."
18He added more infections also increased the chances for that to happen.
19Since Omicron appears to cause less severe disease than Delta, there is hope that it could make the virus milder like a common cold.
20It is a possibility, experts say, given that viruses do not spread well if they kill their hosts very quickly.
21But viruses do not always get less deadly over time.
22Ray explained that a variant could realize its main goal - replicating or reproducing - if it caused mild infections at first then caused severe illness later.
23This would give time for an infected person to spread the virus to others before getting very sick.
24Ray added, "I don't think we can be confident that the virus will become less lethal over time."
25Lethal is a term that means deadly.
26When SARS-CoV-2, the virus that caused COVID-19, first appeared, no one was immune.
27But infections and vaccines have given at least some immunity to much of the world,
28so the virus must change to survive and spread to others.
29There are many possible ways for such change to take place.
30Animals could possibly release new variants.
31Dogs and cats, deer and farm-raised mink are some of the animals that could be infected by the virus.
32The virus could mutate within them and then jump back to people.
33Another possibility is that people could get infected with both Omicron and Delta at the same time.
34Such infections could create what Ray calls "Frankenvariants" with qualities of both variants.
35When new variants do develop, scientists said it is still very difficult to know which ones might spread.
36For example, Omicron has 30 mutations that let it attach easily to human cells.
37But the IHU variant, identified in France, has 46 mutations and does not seem to have spread much at all.
38To control or limit the spread of new variants, scientists stress continuing with public health measures such as wearing face coverings and getting vaccinated.
39Louis Mansky is director of the Institute for Molecular Virology at the University of Minnesota.
40He said with so many unvaccinated people, "the virus is still kind of in control of what's going on."
41I'm John Russell.
1Scientists warn that the fast-spreading Omicron will likely not be the last worrisome version of the coronavirus. 2The Omicron version of the coronavirus was first identified in mid-November. By the first week of January, the World Health Organization reported a record 15 million new COVID-19 cases. That is a 55 percent increase from the previous week. 3Every new infection provides a chance for the virus to mutate, or change. The fast spread of Omicron means the virus has more chances to develop new versions, called variants. 4Scientists do not know what the next variants will look like or how they might shape the pandemic. But they say there is no guarantee that new coronavirus variants will cause milder illness or that existing vaccines will work against them. And they urge wider vaccination now, while the shots still work against the virus. 5Dr. Leonardo Martinez is an infectious disease expert at Boston University. He said, "The faster Omicron spreads, the more opportunities there are for mutation, potentially leading to more variants." 6More contagious, breakthrough infections 7Research shows that Omicron is at least two times as contagious as the Delta variant and four times more contagious than the original version of the virus. Contagious means the variant could easily pass between people. 8Omicron is also more likely than Delta to reinfect individuals who previously had COVID-19 and to cause "breakthrough infections" - meaning to cause an infection even if a person is vaccinated. 9The variant's quick spread increases the chances that the virus will infect and remain inside people with weakened immune systems - giving it more time to develop mutations or changes. 10Dr. Stuart Campbell Ray of Johns Hopkins University said, "It's the longer...infections that seem to be the most likely breeding grounds for new variants." He added more infections also increased the chances for that to happen. 11Other possibilities for the virus 12Since Omicron appears to cause less severe disease than Delta, there is hope that it could make the virus milder like a common cold. It is a possibility, experts say, given that viruses do not spread well if they kill their hosts very quickly. But viruses do not always get less deadly over time. 13Ray explained that a variant could realize its main goal - replicating or reproducing - if it caused mild infections at first then caused severe illness later. This would give time for an infected person to spread the virus to others before getting very sick. 14Ray added, "I don't think we can be confident that the virus will become less lethal over time." Lethal is a term that means deadly. 15When SARS-CoV-2, the virus that caused COVID-19, first appeared, no one was immune. But infections and vaccines have given at least some immunity to much of the world, so the virus must change to survive and spread to others. 16There are many possible ways for such change to take place. 17Animals could possibly release new variants. Dogs and cats, deer and farm-raised mink are some of the animals that could be infected by the virus. The virus could mutate within them and then jump back to people. 18Another possibility is that people could get infected with both Omicron and Delta at the same time. Such infections could create what Ray calls "Frankenvariants" with qualities of both variants. 19When new variants do develop, scientists said it is still very difficult to know which ones might spread. For example, Omicron has 30 mutations that let it attach easily to human cells. But the IHU variant, identified in France, has 46 mutations and does not seem to have spread much at all. 20To control or limit the spread of new variants, scientists stress continuing with public health measures such as wearing face coverings and getting vaccinated. 21Louis Mansky is director of the Institute for Molecular Virology at the University of Minnesota. He said with so many unvaccinated people, "the virus is still kind of in control of what's going on." 22I'm John Russell. 23Laura Ungar reported on this story for the Associated Press. John Russell adapted it for Learning English. 24_____________________________________________________________ 25Words in This Story 26opportunity - n. an amount of time or a situation in which something can be done 27mutation - n. biology : a change in the genes of a plant or animal that causes characteristics that are different from what is normal; a new form of something that has changed 28contagious - adj. able to be passed from one person or animal to another by touching 29immune system- n. the system that protects your body from diseases and infections