- There are four coronavirus variants that experts around the world are particularly worried about.
- These variants were first identified in South Africa, the UK, Brazil, and India respectively.
- Others coronavirus variants have concerning features, but it's not yet clear they're more dangerous.
- See more stories on Insider's business page.
Several coronavirus variants have evolved mutations that mean they spread more easily, make people sicker, escape immune responses, evade tests, or render treatments ineffective.
These are called "variants of concern" by the World Health Organization, and there are four that have spread to the US, including the variant first found in India.
There are various other variants that may have troubling features, which experts are looking into. These are called "variants under investigation."
They differ from the original virus strain in a number of key ways.
Variants of concern
B.1.1.7, first found in the UK
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B.1.1.7 was first detected in two people in south-east England. It was reported to the World Health Organization (WHO) on December 14.
It has been identified in 123 countries worldwide, including the US, where there are more than 20,000 reported cases, according to the CDC. It became the most common variant in the US on April 7. Tennessee has the highest proportion of B.1.1.7 cases of any state, accounting for 73% of sequenced cases.
B.1.1.7 is between 30% to 50% better at spreading from person to person than other coronavirus variants, according to UK scientists.
B.1.1.7 could be more deadly, but we don't know for sure
B.1.1.7 could be more deadly. The UK government's New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) reported a model on January 21 that showed someone infected with B.1.1.7 is 30% to 40% more likely to die than someone with a different variant.
Community-based studies in England, Scotland and Denmark showed that infection with B.1.1.7 in the community causes a higher risk of severe disease requiring hospital treatment and death.
But there is a lot of uncertainty around the numbers. Two studies published in the Lancet Infectious Diseases and the Lancet Public Health on April 13 indicated that B.1.1.7 was more infectious, but didn't cause worse illness in hospitalized patients.
COVID-19 vaccines from Pfizer-BioNTech, Moderna, Johnson & Johnson and AstraZeneca all appear to protect against B.1.1.7.
B.1.351, first identified in South Africa
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B.1.351 was first detected in Nelson Mandela Bay, South Africa, in samples dating back to the beginning of October 2020. It was reported to the WHO on December 18.
It has been found in 84 countries, including the US, where there are 453 cases reported across 36 states and jurisdictions according to the CDC
B.1.351 is thought to be 50% more contagious than the original strain, according to South African health officials.
It's not thought to be more deadly. But there is evidence from South Africa that when hospitals came under pressure because of the variant's spread, the risk of death increased.
B.1.351 may evade the body's immune response
The variant may evade the body's immune response, data suggests. Antibodies work best when they attach snugly to the virus and stop it from entering our cells. The B.1.351 variant has mutations called E484K and K417N at the site where antibodies latch on. In early lab tests, antibodies produced by Pfizer and Moderna's COVID-19 vaccines couldn't attach as well to B.1.351, compared to the original coronavirus.
In a real-world Qatari study reported on May 6, Pfizer's vaccine was 75% effective at preventing infection of varying severity caused by the variant first found in South Africa, called B.1.351, after two doses.
And another real-world study from Israel published on April 10 suggested that Pfizer's vaccine provided less protection against B.1.351 than the original coronavirus. But it was focused on those who have already tested positive for the virus, not total infection rates, so we can't draw firm conclusions.
Johnson & Johnson's COVID-19 vaccine was 64% effective at preventing COVID-19 in trials in South Africa, where 95% infections are caused by B.1.351, and 72% effective in the US, where B.1.351 accounts for less than 1% of sequenced coronavirus tests.
AstraZeneca's COVID-19 vaccine didn't prevent mild to moderate disease caused by B.1.351 in a trial, and we don't yet know if AstraZeneca's shot still protects against severe illness caused by the variant.
It is unlikely that vaccines will become completely useless against the variant. Existing vaccines could be updated and tailored to a new variant within weeks or months, or you may require a booster shot.
P.1, first identified in Brazil, which is twice as contagious
The variant found in Brazil was first detected in four people in Japan, who had traveled from Brazil on January 2. It was identified by the National Institute of Infectious Diseases on January 6, and reported to the WHO that weekend.
It has been found in 45 countries worldwide, including the US, where there have been 497 cases in 31 states, according to the CDC
P.1 is twice as contagious as the original coronavirus - it was initially detected in Amazonas, north-west Brazil, on December 4, and by January 21, 91% of people with COVID-19 in the region were infected with P.1, according to the WHO.
P.1 has similar E484K and K417T mutations as B.1.351, which means it can evade antibody responses.
This could be the reason P.1 reinfects people who have already caught coronavirus - a study published April 14 showed that previous coronavirus infection only offered between 54% and 79% of the protection for P.1 than for other virus strains.
P.1's mutations could also mean that vaccines work less well.
COVID-19 vaccines from Pfizer and AstraZeneca work against P.1. Moderna's hasn't been tested. Johnson & Johnson's COVID-19 vaccine was 68% effective in trials in Brazil, where the variant is the most common strain, compared with its 72% efficacy in the US, where P.1 at the time accounted for 0.1% of sequenced coronavirus tests.
B.1.617, first identified in India
The variant first found in India, B.1.617, is in fact three distinct viruses. Collectively, they have spread to more than 17 countries, according to the WHO. All three have been detected in the US, according to GISAID.
The WHO and UK have designated it a "variant of concern" because it's more infectious than the original virus.
B.1.617 remains a "variant of interest," according to the CDC.
Its mutations include:
- L52R: May make the virus more infectious or it may avoid the antibody response.
- P6814: May make it more infectious.
- E848Q: May help the virus avoid the antibody response.
No studies to date have found that any of the variants first found in India are deadlier than earlier versions of the virus, or that it can evade vaccines.
Variants under investigation
B.1.427/B.1.429, first identified in California
Irfan Khan / Los Angeles Times via Getty Images
The variant first found in California consists of two slightly different mutated forms of the virus, called B.1.427 and B.1.429. It is also called CAL.20C, using another naming system. It was first found in California in July and has now been detected across the US and elsewhere, including in Australia, Denmark, Mexico, and Taiwan, according to the Global Initiative on Sharing Avian Influenza Data (GISAID).
B.1.427/B1.429 are estimated to be about 20% more infectious than the original coronavirus. This is likely because of a mutation called L452R mutation, which in early lab studies was shown to help the virus infect cells.
COVID-19 vaccines haven't yet been tested against this variant specifically. But early lab experiments showed that antibodies produced by previous COVID-19 infections worked only half as well against the variant as they did with the original coronavirus strain.
The CDC considers B.1.426/B1.429 a "variant of concern", which means the CDC experts consider that there's enough evidence that its mutations change its behavior. It remains a "variant under investigation" according to the WHO.
Read more: COVID-19 Vaccine Tracker: AstraZeneca's shot proves safe and effective, and is headed to the FDA
B.1.526/ B.1.525, first identified in New York
These two variants were detected in New York in late 2020. They are "variants of interest" because they have mutations that could evade antibody responses. B.1.525 accounts for less than 0.5% of sequenced coronavirus tests in the US, according to the CDC.
B.1.526, first identified in New York
These two variants were detected in New York in late 2020. They are "variants of interest" because they have mutations that may evade antibody responses. B.1.526 accounts for under 9% of sequenced coronavirus tests in the US, according to the CDC.
P.2, first identified in Brazil
P.2 was first detected in Brazil in April 2020. It's a "variant of interest" because it has the E484K mutation that may mean it evades antibody responses. Less than 0.2% of sequenced coronavirus tests in the US are P.2, according to the CDC.
P.3, first identified in the Philippines
P.3 was first detected in the Philippines in February. P.3 has the E484K mutation that may mean it evades the immune response. P.3 hasn't yet been detected in the US.
B.1.525, first found in UK and Nigeria
B.1.525 was first found in the UK and Nigeria in December 2020. It has the E484K mutation that may mean it evades the antibody response. Less than 0.5% of sequenced coronavirus tests in the US, according to the CDC.
B.1.617, first found in France
B.1.617 was first found in France in January. It hasn't been detected in any other countries. It may have mutations that mean it can evade tests.
Human behavior can help stop them spreading
Elizabeth Conley/Houston Chronicle/Pool via Reuters
The WHO has said that everyone should double down on precautions that stop the spread of variants, such as social distancing, hand-washing, mask wearing, and avoiding crowds.
"Human behavior has a very large effect on transmission - probably much larger than any biological differences in SARS-CoV-2 variants," Paul Bieniasz, a virologist at the Howard Hughes Medical Institute, told Insider.
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