In a study posted on Sunday that is yet to be peer-reviewed, researchers have reported seven new variants of the SARS-CoV-2 virus in the US. Researchers are tracking virus variants since some of them might be more deadly than the original virus, they may be more easily transmissible and can have repercussions on the effectiveness of vaccines.
B.1.1.7: This variant emerged in the UK and may be associated with an increased risk of death compared with other variants, the US Centers for Disease Control and Prevention (CDC) has said.
B.1.351: This variant emerged independently from the UK variant and was first identified in South Africa. It was also reported in the US by the end of January 2021.
P.1: This variant emerged in Brazil and is known to have 17 unique mutations. Three of them are in the receptor-binding domain of the spike protein (the spike protein, which protrudes from the surface of the virus is one of the key reasons that SARS-CoV-2 has been able to spread so rapidly and therefore, any mutations that affect the spike protein are important to understand).
The authors of the recent study say that in areas where the prevalence of the virus is high, selection pressures might have favoured the emergence of variants that evade neutralising antibodies (the proteins that prevent the virus from infecting once it is inside the body). The seven new lineages noted by the researchers have all evolved a mutation in the same genetic letter, which affects the way the virus enters the human cells. But it is not yet clear if this mutation makes these new variants more contagious and more dangerous.
Further, there are likely more variants of the virus across the world, but only genome sequencing can help determine that, which is not happening sufficiently at the moment. In a document published in late December 2020, the Ministry of Health and Family Welfare outlined some steps it will take to increase and expand genome sequencing of the virus. One of the steps outlined includes sending five per cent of the positive samples to ten regional genome sequencing labs spread across the country.
Evolution helps organisms to change in response to certain changes in the environment. The goal here is to help the organism adapt so it can survive. In the Naked Ape trilogy, zoologist Desmond Morris writes about how humans have adapted to their changing environment over the course of millions of years of evolution. For instance, he considers the effects of urban city life on humans. Morris argues that despite city life being lonely and more stressful, people flock to them because a city, acts as a giant stimulus-centre where our great inventiveness can flourish and develop.
Since viruses can only replicate within a host cell, their evolution is influenced by their hosts. This means that the virus will mutate in order to evade the defenses that its hosts put up for it.
The book, Medical Microbiology says that as compared to DNA viruses, RNA viruses (SARS-CoV-2 is an RNA virus) have much higher mutation rates, probably one mutation per genome copy. Mutations might be deleterious, neutral and occasionally, they may be favourable. The book notes that only those mutations that do not interfere with the essential virus functions can persist in a given population.
An article in Nature says that compared to the HIV virus that causes AIDS, the SARS-CoV-2 virus is changing much more slowly as it spreads.
But like humans influence the evolution in viruses, viruses too, have shaped the way humans have evolved. In a 2016 study published in the journal eLife, the authors note that the constant battle between pathogens and their human hosts has long been recognised as a key driver of evolution. In this study, the authors note that about 30 per cent of all protein (proteins help cells to perform their functions) adaptations in humans since their divergence from chimpanzees have been driven by viruses. Significantly, during epidemics or pandemics, the population targeted by a virus will either go extinct, or it will adapt.
Once a virus has entered the body of its host, in order to infect the host it starts replicating, which means making copies of its entire genetic sequence. But every once in a while, the virus makes mistakes during replication. A blog entry on the website of Harvard University, explains that these mistakes, typically a change in a single letter (each coronavirus has about 30,000 RNA letters) among the thousands in the viruss sequence, might change the properties of the viruss proteins and therefore, change its capabilities. This change is called a mutation and if it is a favourable mutation, it can give the virus a new ability that promotes its reproduction, which helps the virus to become more widespread over generations.
It is likely that such kinds of favourable mutations in the SARS-CoV-2 virus are giving rise to emerging variants. For instance, the UK variant is known to be about 25-40 per cent more infectious than the original virus.
In a comment in the journal Nature, two immunologists, Dennis Burton and Eric Topol have called for an alternative approach to pandemic preparedness. In this approach, resources should be spent on developing pan-virus vaccines that can provide immunisation against multiple strains of a virus.
This is necessary in the context of SARS-CoV-2, since it is already evolving and initial evidence shows that some of its strains are more easily transmissible, implying that as more variants of the virus emerge, vaccines that already exist could be less effective against them.
While there are hundreds of coronaviruses that are known to infect animals such as pigs, camels, bats and cats, till date, seven types of coronaviruses have been identified to infect humans. In humans, the viruses usually cause mild to moderate upper-respiratory tract illnesses such as the common cold. In the last two decades, however, more aggressive coronaviruses have emerged that are capable of causing serious illness and even death in humans. These include SARS-CoV, MERS and now SARS-CoV-2.
The first coronavirus was found to infect humans in 1965, when scientists DJ Tyrrell and ML Bynoe isolated a strain of the virus called B814 from the nasal washing of a male child who had symptoms of common cold.
Vaccine development for the first four human coronaviruses, which include HCoV-229E (one of the first strains to be described in the mid-1960s), HCoV-OC43 (discovered between mid-late 1960s), HCoV-NL63 and HCoV-HKU1 (NL63 and HKU1 both discovered in Hong Kong in early 2005) was not a priority since these cause only mild illness. It was only two decades ago when SARS-CoV was emerging in China around 2003 that the need to develop a vaccine was felt since it was the first example of a human coronavirus that could cause serious illness.
Writing in the Journal of Biomedical Science, authors note that while various forms of vaccines have been developed and tested in preclinical models for SARS and MERS, none of them have been approved by the FDA.
The answer potentially lies in the spike protein of the virus, a number of which protrude from the surface of the virus forming a crown, which gives the virus its name. The spike protein makes it easier for the virus to bind with the ACE2 receptor (both SARS-CoV and SARS-CoV-2 bind to this receptor) in human cells, after which the virus starts infecting its host. But this spike protein, which makes transmission easier, is also one reason that vaccines for SARS-CoV-2 have been developed at a faster pace compared to the previous two human coronaviruses SARS and MERS, for which an approved vaccine still does not exist.
In particular, vaccine design for SARS-CoV-2 has been made faster because the spike protein offers a larger area for the vaccine to target, making it easier for it to trigger the bodys immune system into making neutralising antibodies, the proteins that prevent the spike protein from binding with the receptor and initiating infection.
Explained: Are new Covid-19 variants detected in the US more contagious? - The Indian Express
- Coronavirus news live: Latest as lockdown easing sees shops and pubs crowded - The Independent - April 12th, 2021
- Covid UK: coronavirus cases, deaths and vaccinations today - The Guardian - April 12th, 2021
- Asia Today: India records another surge in COVID-19 cases - The Associated Press - April 12th, 2021
- The Pfizer/BioNTech Covid-19 Vaccine Is Less Effective Against The South African And UK Variants Than Against The Original Virus, According To A New... - April 12th, 2021
- How Long Should You Wait To Get the Vaccine After Having COVID-19? - ideastream - April 9th, 2021
- What you should (and shouldn't) do with your vaccination card - KING5.com - April 9th, 2021
- UC Davis Health opening vaccinations up to anyone 16 and older | COVID-19 Updates in Northern California - ABC10.com KXTV - April 7th, 2021
- Can Vaccinated People Spread the Virus? - The New York Times - April 5th, 2021
- Germany to restrict AstraZeneca use in under-60s over clots - The Associated Press - April 5th, 2021
- The COVID-19 vaccine side effects you can expect based on your age, sex, and dose - Business Insider - April 5th, 2021
- Covid-19: Johnson & Johnson Put in Charge of Plant That Ruined Millions of Vaccine Doses - The New York Times - April 5th, 2021
- Germany restricts use of AstraZeneca vaccine to over 60s in most cases - DW (English) - April 5th, 2021
- Coronavirus vaccines with a side of fried fish are on the Good Friday menu in Central City - NOLA.com - April 3rd, 2021
- Explained: Making sense of Indias Covid-19 data - The Indian Express - April 3rd, 2021
- 35 Pa. counties have substantial spread of COVID-19; positive test rate rises for second week in a row - PennLive - March 30th, 2021
- Covid-19 News: In-Person School Attendance Inches Up but Roadblocks Remain - The New York Times - March 30th, 2021
- COVID-19 cases surging in Pa. and N.J. as variants spread; Biden sets goal of 200 million vaccinations by end - The Philadelphia Inquirer - March 28th, 2021
- Why Supply Isnt the Only Thing Stymying Europes Coronavirus Vaccine Rollout - The New York Times - March 26th, 2021
- All Georgia adults will be eligible for coronavirus vaccines starting Thursday - Atlanta Journal Constitution - March 26th, 2021
- COVID Vaccine (COVID-19 Immunization Updates) | CVS Pharmacy - March 24th, 2021
- Mavericks won't require their players to get the coronavirus vaccine - The Official Home of the - Mavs.com - March 24th, 2021
- Health experts give green light to Janssen COVID jab, allay clotting concerns - UN News - March 20th, 2021
- New York City marks anniversary of 1st COVID-19 death with memorial services - ABC News - March 15th, 2021
- Will I have to wear a mask after getting the Covid vaccine? The science explained - The Guardian - March 15th, 2021
- Health Department ignored red flags in Philly Fighting COVID partnership, inspector general says - The Philadelphia Inquirer - March 11th, 2021
- Coronavirus vaccination scam calls reported in Bay and Saginaw counties - MLive.com - March 11th, 2021
- When will children be able to get COVID-19 vaccines? - KHOU.com - March 8th, 2021
- What you need to know about the new Johnson & Johnson vaccine - WHYY - March 8th, 2021
- People who have had COVID-19 might need only one shot of a coronavirus vaccine - Science News Magazine - March 6th, 2021
- "Corona Virus Vaccine Market Size is Projected to reach 75.75 Billion by end of 2021, Says Brandessence Market Research" - PR Newswire India - March 6th, 2021
- Who should skip the second shot of coronavirus vaccine? Weve got answers - cleveland.com - March 4th, 2021
- Explained: As you take the Covid-19 vaccine, some dos and donts - The Indian Express - March 4th, 2021
- "Corona Virus Vaccine Market Size is Projected to reach 75.75 Billion by end of 2021, Says Brandessence Market Research" USA - PRNewswire - March 4th, 2021
- Indias Covid-19 Vaccine Is Found Effective, Boosting National Efforts - The Wall Street Journal - March 4th, 2021
- Latest COVID-19 vaccination numbers in DC, Maryland and Virginia - WTOP - March 4th, 2021
- Situation Update: Response to COVID-19 in Indonesia (As of 1 March 2021) [EN/ID] - Indonesia - ReliefWeb - March 4th, 2021
- Dietary Supplement Use and COVID-19: What You Need to Know - JD Supra - March 4th, 2021
- Texas is diverting thousands of COVID-19 vaccine doses away from Dallas County, Judge Jenkins says - WFAA.com - March 2nd, 2021
- The latest on the coronavirus pandemic and vaccines: Live updated - CNN - March 2nd, 2021
- FDA Issues Emergency Use Authorization for Third COVID-19 Vaccine - FDA.gov - February 28th, 2021
- Coronavirus UK news update Covid alert drops from 5 to 4 as Queen asks Brits wary of vaccine to think abo - The Sun - February 26th, 2021
- Who is next on the priority list for Covid vaccines - and how will I be contacted? - Telegraph.co.uk - February 26th, 2021
- The Covid-19 vaccines reduce transmission. Heres the evidence. - Vox.com - February 24th, 2021
- India's Covid vaccine maker told to meet domestic demand first, urges 'rest of the world' to be patient - CNBC - February 24th, 2021
- Governor Lamont Announces Connecticut Will Continue Age-Based Approach To COVID-19 Vaccine Eligibility; Educators and Childcare Providers To Have... - February 24th, 2021
- Australian Open crowd boos at mention of coronavirus vaccines and Victorian government after Novak Djokovic's win - ABC News - February 22nd, 2021
- Quixplained: What is the South African variant of Covid-19? - The Indian Express - February 20th, 2021
- Texas power outage, storm delay COVID-19 vaccine deliveries, injections - The Texas Tribune - February 20th, 2021
- How many Covid vaccinations have been given in my area? Use our postcode tool to find out - Telegraph.co.uk - February 20th, 2021
- Who is next on the priority list for Covid vaccines - and how will I be contacted? - The Telegraph - February 20th, 2021
- COVID-19 tests, not to be confused with vaccine, in LA to be available without appointment next week - FOX 11 Los Angeles - February 20th, 2021
- New coronavirus variants are emerging across the globe: Everything we know - CNET - February 18th, 2021
- Heres why some coronavirus vaccine suppliers say they arent selling to provinces - Global News - February 18th, 2021
- More Than 4 Million Doses of COVID-19 Vaccine Have Been Given in Texas; Supersites Arrive Next Week - NBC 5 Dallas-Fort Worth - February 16th, 2021
- The superspreaders behind top COVID-19 conspiracy theories - The Associated Press - February 16th, 2021
- India is set to become a vital Covid vaccine maker perhaps second only to the U.S. - CNBC - February 16th, 2021
- Oxford Covid-19 vaccine Q&A: How effective is it, and how is it different to the Pfizer vaccine? - Telegraph.co.uk - February 16th, 2021
- Boris Johnson says move to ease lockdown will be irreversible - The Independent - February 16th, 2021
- 78-Year-Old Woman Dies After Receiving COVID-19 Vaccine; No Link Suspected - NBC Southern California - February 14th, 2021
- Here's Who Will Be Eligible for the COVID Vaccine in Illinois Starting Next Week - NBC Chicago - February 14th, 2021
- Coronavirus UK news LIVE Britain to hit 15m Covid vaccination target TODAY as plan to get out of lockdown l - The Sun - February 14th, 2021
- A doctor had 6 hours to use a vial of COVID-19 vaccine before it expired, so he gave the shots to 10 people. For that, he was fired. - Chicago Tribune - February 12th, 2021
- Memphis surgeon dies of COVID-related illness weeks after receiving second COVID vaccine - WREG NewsChannel 3 - February 12th, 2021
- Where to sign up for COVID-19 vaccine in Austin, Travis County area - KXAN.com - February 11th, 2021
- Pfizer and Moderna's COVID-19 vaccines are just the beginning. Will Australia miss out on the mRNA medical revolution? - ABC News - February 9th, 2021
- Covid UK news LIVE Over 70s URGED to chase coronavirus vaccine slots as Brits told too early to book summe - The Sun - February 9th, 2021
- UK coronavirus LIVE: Brits face third AstraZeneca vaccine as over-70s urged to contact NHS for jab - Evening Standard - February 9th, 2021
- LIVE BLOG: North Carolina bills for COVID-19 relief, mandatory in-person schooling working through General Assembly - WXII12 Winston-Salem - February 6th, 2021
- New COVID-19 prediction models forecast a potential fourth wave and how to minimize it - GeekWire - February 6th, 2021
- Covid UK news Most adults will be vaccinated by May leaked letter reveals as it emerged pub curfew to be s - The Sun - February 6th, 2021
- The priority list for the Covid vaccines - and how you will be contacted - Telegraph.co.uk - February 6th, 2021
- Select Texas CVS Pharmacy locations to begin administering COVID-19 vaccines next week - KXAN.com - February 4th, 2021
- The Second COVID-19 Shot Is a Rude Reawakening for Immune Cells - The Atlantic - February 4th, 2021
- You think it's taking too long for Covid vaccination? Global Vaccine Timeline stretched to 2023! - Sierra Wave - February 4th, 2021
- What to Know About Covid-19 and the 2021 Super Bowl - The New York Times - February 4th, 2021
- A Primer on the COVID-19 Vaccines Available in the United States - Davidson News - February 1st, 2021
- Go read this story about how bad software helped slow coronavirus vaccine distribution - The Verge - February 1st, 2021
- Tax season 2021: Stimulus payments, unemployment and every other major change - CNET - January 30th, 2021
- Oregon COVID-19 vaccine update: More than 300,000 people have received at least one dose - KGW.com - January 30th, 2021
- How to get the COVID-19 vaccine from Walgreens - WFLA - January 29th, 2021