COVID-19 vaccines: Get the facts


What COVID-19 vaccines have been authorized and how do they work?

Currently, several COVID-19 vaccines are in clinical trials. The FDA will review the results of these trials before approving COVID-19 vaccines for use. But because there is an urgent need for COVID-19 vaccines and the FDA’s vaccine approval process can take months to years, the FDA will first be giving emergency use authorization to COVID-19 vaccines based on less data than is normally required. The data must show that the vaccines are safe and effective before the FDA can give emergency use authorization. Vaccines with FDA emergency use authorization include:

  • Pfizer-BioNTech COVID-19 vaccine. The Pfizer-BioNTech COVID-19 vaccine is 95% effective in preventing the COVID-19 virus with symptoms in people age 16 and older. The vaccine is 100% effective in preventing the COVID-19 virus in children ages 12 through 15. This vaccine is for people age 12 and older. It requires two injections given 21 days apart. The second dose can be given up to six weeks after the first dose, if needed.
  • Moderna COVID-19 vaccine. The Moderna COVID-19 vaccine is 94% effective in preventing the COVID-19 virus with symptoms. This vaccine is for people age 18 and older. It requires two injections given 28 days apart. The second dose can be given up to six weeks after the first dose, if needed.
  • Janssen/Johnson & Johnson COVID-19 vaccine. In clinical trials, this vaccine was 66% effective in preventing the COVID-19 virus with symptoms — as of 14 days after vaccination. The vaccine also was 85% effective at preventing severe disease with the COVID-19 virus — at least 28 days after vaccination. This vaccine is for people age 18 and older. It requires one injection. The FDA and the Centers for Disease Control and Prevention (CDC) have recommended that use of this vaccine continue in the U.S. because the benefits outweigh the risks. If you are given this vaccine, you should be educated about the possible risks and symptoms of a blood clotting problem.

Both the Pfizer-BioNTech and the Moderna COVID-19 vaccines use messenger RNA (mRNA). Coronaviruses have a spikelike structure on their surface called an S protein. COVID-19 mRNA vaccines give cells instructions for how to make a harmless piece of an S protein. After vaccination, your cells begin making the protein pieces and displaying them on cell surfaces. Your immune system will recognize that the protein doesn’t belong there and begin building an immune response and making antibodies.

The Janssen/Johnson & Johnson COVID-19 vaccine is a vector vaccine. In this type of vaccine, genetic material from the COVID-19 virus is inserted into a different kind of weakened live virus, such as an adenovirus. When the weakened virus (viral vector) gets into your cells, it delivers genetic material from the COVID-19 virus that gives your cells instructions to make copies of the S protein. Once your cells display the S proteins on their surfaces, your immune system responds by creating antibodies and defensive white blood cells. If you become infected with the COVID-19 virus, the antibodies will fight the virus.

Viral vector vaccines can’t cause you to become infected with the COVID-19 virus or the viral vector virus. Also, the genetic material that’s delivered doesn’t become part of your DNA.

Here’s a summary of tonight’s developments

  • Spain loosened outdoor mask requirements today for the first time in over a year.
  • Brazil recorded 64,134 new coronavirus cases on Saturday and 1,593 new deaths. Overall the country has reported more than 18.3m cases and 512,735 deaths.
  • Thailand has announced new restrictions around Bangkok as the country suffers its worst coronavirus outbreak. The new measures, to be in place for 30 days, include a ban on eating in at restaurants in the capital and five surrounding provinces.
  • Former UK chancellor and home secretary Sajid Javid has been appointed health secretary following Matt Hancock’s resignation, Downing Street announced.
  • The US has administered more than 322m vaccine doses, the Centers for Disease Control and Prevention (CDC) announced. So far, 178,873,816 people in the US have received at least one shot and 152,184,243 are fully vaccinated.
  • UK health secretary Matt Hancock has resigned, saying the government “owe it to people who have sacrificed so much in this pandemic to be honest when we have let them down”. It came after he apologised for kissing his closest aide.
  • An investigation is underway in Mallorca following a coronavirus outbreak involving over 600 students visiting from the Spanish mainland. At least 1,000 students have had to go into isolation.
  • The UK recorded 18,270 new coronavirus infections – the highest daily rise since 5 February – and 23 deaths. Cases have been rising in Britain for the last month.

That’s it from me for this evening. Thank you for reading.

AstraZeneca’s COVID-19 vaccine: benefits and risks in context

AstraZeneca COVID-19 Vaccine Linked With Small Risk Of Low Blood Platelets: Study

Vaxzevria (formerly COVID-19 Vaccine AstraZeneca) is authorised in the EU to prevent COVID-19, which can cause severe disease and death. The disease can also have long-term consequences in people of all ages, including in otherwise healthy people.

The benefits of Vaxzevria outweigh its risks in adults of all age groups; however, very rare cases of blood clots with low blood platelets1 have occurred following vaccination.

To support national authorities making decisions on how to best use the vaccine in their territories, EMA’s human medicines committee (CHMP) has further analysed available data to put the risk of these very rare blood clots in the context of the vaccine’s benefits for different age groups and different rates of infection.

The analysis will inform national decisions on the roll out of the vaccine, taking into account the pandemic situation as it evolves and other factors, such as vaccine availability. The analysis could change as new data become available.

The Committee also considered available data on the use of the second dose.

Known benefits and risk of Vaxzevria

Vaxzevria is effective at preventing hospitalisations, intensive care unit (ICU) admissions and deaths due to COVID-19. The most common side effects are usually mild or moderate and get better within a few days. The most serious side effects are very rare cases of unusual blood clots with low blood platelets, which are estimated to occur in 1 in 100,000 vaccinated people. People should seek medical assistance if they have symptoms.

What data show for age groups and infection rates

The Committee analysed the vaccine’s benefits and the risk of unusual blood clots with low platelets in different age groups in the context of the monthly infection rates: low (55 per 100,000 people), medium (401 per 100,000 people) and high (886 per 100,000 people).2

The analysis looked at prevention of hospitalisations, ICU admissions and deaths due to COVID-19, based on different assumptions of vaccine effectiveness to contextualise the occurrence of these unusual blood clots. It showed that the benefits of vaccination increase with increasing age and infection rates.

There were insufficient data available from across the EU to provide further context on benefits and risks with regard to sex.

PDF icon Graphic representations of the findings , assuming an 80% vaccine effectiveness over a period of four months, are available. The CHMP’s assessment report with the full data will be published shortly. The current analysis does not constitute an assessment of the vaccine’s benefit-risk balance, which remains positive for adults in all age groups.

As for all vaccines, Vaxzevria is approved in the EU because its benefits outweigh the risks for an individual potentially exposed to the agent causing disease. However, national authorities later consider other factors when deciding how to best use the vaccines. Because vaccination is a public health intervention, national authorities could also consider the benefits to the population as a whole, as vaccines may protect more people than are vaccinated.  

While this analysis may be subject to change as new data become available, it may guide EU Member States when they adjust their vaccination strategies depending on the infection rates and ages of people who still need to be vaccinated.

Second dose of Vaxzevria

The Committee recommended to continue giving a second dose of Vaxzevria between 4 and 12 weeks after giving the first one in line with the product information.

The CHMP considered recommendations to give the second dose of Vaxzevria after a longer interval than the recommended 4-12 weeks, to not give a second dose at all, or to give an mRNA vaccine as a second dose.

However, there has not been enough exposure and follow-up time to determine whether the risk of blood clots with low blood platelets after a second dose will differ from the risk after the first dose. At present there are no or limited data to change current recommendations.

Update on COVID-19 numbers

  • More than 3.7 million people have died from COVID-19 globally.
  • Over half of U.S. adults are now fully vaccinated.
  • COVID-19 cases remain high in some parts of the world, like India, where few people have been vaccinated.

Update on COVID-19 numbers

  • Globally, there have been more than 172.3 million confirmed COVID-19 cases and 3.7 million associated deaths, according to Johns Hopkins University.
  • The United States has reported more than 33.3 million confirmed cases and more than 596,000 associated deaths.
  • Currently, more than 169.7 million U.S. people have received their first COVID-19 vaccine dose. More than 137.4 million people are fully vaccinated, according to the CDC.

Healthline updates this page on weekdays. For up-to-date information about the virus, go here.

6/4/21 4:10 p.m. PDT — CDC director urges teens to get vaccinated

Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), urged teens to get vaccinated and recommended parents who have questions to speak with their child’s health providers, local pharmacists, or health departments, reported The Washington Post.

“I strongly encourage parents to get their teens vaccinated, as I did mine,” she said during a briefing yesterday, reported the Post.

Walensky added that until teens are fully vaccinated, “they should continue to wear masks and take precautions when around others who are not vaccinated to protect themselves, their friends, family and community.”

6/3/21 12:00 p.m. PDT — Biden administration outlines plan to send 25 million vaccines to other countries

With vaccination demand in the United States waning, the Biden administration is now looking to send millions of doses abroad to fight COVID-19, according to Reuters.

About 19 million doses will be given to COVAX, the campaign run by the World Health Organization to get vaccines to developing countries. The other 6 million doses will be given directly to countries including Canada, Mexico, India, and South Korea.

While more than 50 percent of the U.S. population has had at least one COVID-19 vaccine dose, many countries have yet to even start a mass vaccination campaign.

The World Health Organization has been pushing for wealthier countries to donate vaccines to poorer countries to fight the pandemic globally. Should a strain develop in other parts of the world, it can quickly spread to the United States.

COVID-19 cases lowest since pandemic began

The United States has brought new COVID-19 cases down to their lowest level since the pandemic began in March 2020.

The country averaged about 15,622 new cases per day over the past week, which is a 30 percent improvement over the week before. Also, new cases declined in 43 states, with the other seven holding steady, reported Axios.

Additionally, since vaccinations are rising, there’s less chance that we could see another major spike similar to what we saw this winter.

According to a recent story in The Washington Post, the risk for unvaccinated people is still about as high as it’s ever been, with an average of roughly 500, mostly unvaccinated, people dying per day from COVID-19 in the United States.

India orders unapproved COVID-19 vaccine as nation struggles against second wave

Today, India signed its first order for an unapproved COVID-19 vaccine, one day after criticism from the South Asian country’s supreme court over a bungled vaccine rollout that left millions of people vulnerable after almost 338,000 deaths, reported Reuters.

According to Reuters, only 4.7 percent of the 950 million adult population has received two vaccine doses, as the world’s second most populous country reels from a nationwide second wave of infections that has killed about 170,000 people in April and May alone.

The government will buy 300 million vaccine doses from local firm Biological-E, and has put down an advance of $205.6 million, the health ministry said, even though the vaccine is still going through phase 3 clinical trials, reported Reuters.

“The arrangement with Biological-E is part of the wider endeavor of the government of India to encourage indigenous vaccine manufacturers by providing them support in research & development and also financial support,” the ministry said in a statement, reported CTV News.

According to CTV News, the official recorded caseload since the start of the pandemic now stands at 28.4 million, which is the second-highest in the world after the United States.

6/2/21 7:00 p.m. PDT — 12 states have already achieved Biden’s goal of 70% adults vaccinated against COVID-19

Twelve states have now reached the Biden administration’s goal to vaccinate 70 percent of adults with at least one dose of a COVID-19 vaccine by July 4, according to data published yesterday by the Centers for Disease Control and Prevention (CDC), reported CNN.

According to CNN, those states are California, Maryland, Connecticut, Hawaii, Maine, Massachusetts, New Hampshire, New Jersey, New Mexico, Pennsylvania, Rhode Island, and Vermont.

About 168.5 million people — nearly 51 percent of the U.S. population — have received at least one dose of a COVID-19 vaccine, and nearly 41 percent of the population — roughly 136 million people — are fully vaccinated, according to CDC data, CNN reported.

New trial will research whether COVID-19 vaccines can be mixed and matched

The National Institutes of HealthTrusted Source is examining whether COVID-19 vaccines can be mixed and matched for booster shots.

The NIH study will see whether fully vaccinated people do better if they receive a booster shot 20 weeks after initial vaccination. Those new booster shots will not need to match the original type of vaccine given to the participant.

“We need to prepare for the possibility of needing booster shots to counter waning immunity and to keep pace with an evolving virus,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, which is part of the NIH.

“The results of this trial are intended to inform public health policy decisions on the potential use of mixed vaccine schedules should booster doses be indicated,” he said.

6/1/21 2:55 p.m. PDT — COVID variants to be named after Greek letters, WHO announces

The World Health Organization (WHO)Trusted Source will assign simple, easy to say and remember labels for key variants of SARS-CoV-2, the virus that causes COVID-19, by using letters of the Greek alphabet.

The WHO will assign labels for COVID-19 variants designated as Variants of Interest (VOI) or Variants of Concern (VOC) by WHO, and will be posted on the WHO’s website.

“The U.K. variant, for instance, is labeled Alpha, the South African Beta, and the Indian as Delta,” reported BBC. The WHO said this was to simplify discussions but also to help remove some stigma from the names.

“No country should be stigmatized for detecting and reporting variants,” the WHO’s COVID-19 technical lead, Maria Van Kerkhove, PhD, tweeted. Kerkhove also called for “robust surveillance” of variants and the sharing of scientific data to help stop the pandemic from worsening.


Scientists believe that the variant is more transmissible and cases of it nearly tripled to 1,313 in the past week in England.

But Matt Hancock said early lab data showed vaccines remained effective.

He said the majority of those in hospital in Bolton – a hotspot for the Indian variant – were unvaccinated.

The health secretary said that the variant, known as B.1.617.2, was “relatively widespread in small numbers” in most of the country.

It comes as England is due to move to stage three of the government’s roadmap for easing lockdown on Monday, with socialising in groups of six indoors as well as some international travel to be allowed.

On Friday Prime Minister Boris Johnson warned the variant could pose “serious disruption” to the final stage of lockdown easing in England on 21 June.

India covid-19 double mutacion

A new “double mutant” variant of the coronavirus has been detected from samples collected in India.

Officials are checking if the variant, where two mutations come together in the same virus, may be more infectious or less affected by vaccines.

Some 10,787 samples from 18 Indian states also showed up 771 cases of known variants – 736 of the UK, 34 of the South African and one Brazilian.

Officials say the variants are not linked to a spike in cases in India.

India reported 47,262 cases and 275 deaths on Wednesday – the sharpest daily rise this year.

The Indian SARS-CoV-2 Consortium on Genomics (INSACOG), a group of 10 national laboratories under India’s health ministry, carried out genomic sequencing on the latest samples. Genomic sequencing is a testing process to map the entire genetic code of an organism – in this case, the virus.

The genetic code of the virus works like its instruction manual. Mutations in viruses are common but most of them are insignificant and do not cause any change in its ability to transmit or cause serious infection. But some mutations, like the ones in the UK or South Africa variant lineages, can make the virus more infectious and in some cases even deadlier.

Virologist Shahid Jameel explained that a “double mutation in key areas of the virus’s spike protein may increase these risks and allow the virus to escape the immune system”.

The spike protein is the part of the virus that it uses to penetrate human cells.

The government said that an analysis of the samples collected from India’s western Maharashtra state showed “an increase in the fraction of samples with the E484Q and L452R mutations” compared with December last year.

“Such [double] mutations confer immune escape and increased infectivity,” the health ministry said .

Dr Jameel added that “there may be a separate lineage developing in India with the L452R and E484Q mutations coming together”.


Are double mutants a worry?

Soutik Biswas, BBC News, Delhi

Mutations in the spike gene can make the virus inherently “better” at infecting people or can help the virus to escape neutralising antibodies.

This means if the virus mutates in the “right way”, it can reinfect someone who has already recovered from Covid-19.

But scientists say reinfections will be very mild compared to primary infections in people who are vaccinated or who recovered already from an earlier case of Covid-19.

But if the virus can use reinfection to spread, then it would be “penetrating” herd immunity, says Dr Jeremy Kamil, a virologist at Louisiana State University Health Sciences Center Shreveport. (Herd immunity happens when a large portion of a community becomes immune to a disease through vaccination or through the mass spread of the disease.)

This puts the most vulnerable people at risk of severe disease, since the virus can move through the herd to reach them.

He says unlike some other variants, India’s new double variant is not likely to be more deadly or more inherently transmissible, but that more data is needed to be sure.


The Indian government denies that the rise in cases is linked to the mutations.

“Though VOCs [variants of concern] and a new double mutant variant have been found in India, these have not been detected in numbers sufficient to either establish a direct relationship or explain the rapid increase in cases in some states,” the health ministry said.

The recent report comes after several experts had asked the government to step up genome sequencing efforts.

“We need to constantly monitor and make sure none of the variants of concern are spreading in the population. The fact that it is not happening now doesn’t mean it will not happen in the future. And we have to make sure that we get the evidence early enough,” Biswas earlier this month.

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India became the fifth country in the world to sequence the genome of the novel coronavirus after isolating it from some of the first cases recorded in January last year.

More than 11.7 million cases and 160,000 deaths later, efforts are continuing to identify mutations.

The latest surge – which began this month – comes during what some experts have called a “delicate phase” for India – the healthcare system is already exhausted from a year-long battle against the coronavirus.

States have already begun re-introducing restrictions, including curfews and intermittent lockdowns.

Two major cities, Delhi and Mumbai, have also ordered randomised rapid tests at airports, railway stations and crowded areas such as shopping malls.

What You Need to Know About the Coronavirus

Over 95 percent of Americans killed by COVID-19 have been 50 or older

Coronavirus & COVID-19 Overview: Symptoms, Risks, Prevention, Treatment &  More
  • FDA, CDC urge pause of J&J vaccine. The U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) issued a joint statement on April 13 recommending that use of Johnson & Johnson’s single-dose COVID-19 vaccine be paused “out of an abundance of caution” while the agencies investigate six cases of a rare and serious type of blood clot, in combination with low levels of platelets, in women in the United States. As of April 12, more than 6.8 million doses of the J&J vaccine had been administered, so these incidents “appear to be extremely rare,” the statement says. The six women who experienced the clot are between the ages of 18 and 48 and the clots occurred between six and 13 days after they received the J&J shot. The statement urges people who have received the J&J vaccine and develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after their vaccination to contact their health care provider. The J&J vaccine was created using a different technology than the Pfizer-BioNTech and Moderna vaccines, and the federal agencies are not recommending any pause of those two products. A CDC advisory committee on April 14 voted to keep the pause in place until more information is available.
  • Leaving middle seats open on airplanes can reduce COVID exposure. A new CDC report based on a laboratory model found that when middle seats were left open on airplanes, risk of exposure to coronavirus particles was reduced by 23 to 57 percent, compared with full aircraft occupancy. However, it’s not yet understood whether the extra space could decrease virus transmission and infection. “Based on a data-driven model, approaches to physical distancing, including keeping middle seats vacant, could reduce exposure to SARS-CoV-2 on aircraft,” the authors write. Current CDC guidelines recommend delaying travel unless you are fully vaccinated.
  • Infections and hospitalizations continue to rise. The seven-day average of daily COVID-19 cases continues to rise and is now nearing 70,000 daily cases, according to CDC data. Hospitalizations are also on the rise — up about 7 percent from the previous seven-day period.
  • Drugmaker Regeneron to seek expanded authorization for antibody treatment. A phase 3 trial for Regeneron’s monoclonal antibody cocktail, REGEN-COV, found the drug has some preventive benefits. It significantly reduced the risk for COVID-19 infection in individuals living infected persons, the company reported on April 12. In individuals who developed symptomatic infections, the drug, given by injection, was found to shorten the duration of disease. “These data suggest that REGEN-COV can complement widespread vaccination strategies, particularly for those at high risk of infection. Importantly, to date REGEN-COV has been shown in vitro to retain its potency against emerging COVID-19 variants of concern,” said Myron Cohen, M.D., who leads the monoclonal antibody efforts for the NIH-sponsored COVID Prevention Network (CoVPN) and is Director of the Institute for Global Health & Infectious Diseases at the University of North Carolina at Chapel Hill. Regeneron says it plans to submit the data to the U.S. Food and Drug Administration (FDA) to expand its authorization to include COVID-19 prevention “for appropriate populations.” 
  • Two new CDC reports highlight racial and ethnic disparities during the pandemic. In each region of the country, the proportion of hospitalized COVID-19 patients was highest among Hispanics and Latinos, a new report from the Centers for Disease Control and Prevention (CDC) shows. A second study released by the CDC found that Hispanic and American Indian and Alaskan Native individuals were 1.7 times more likely to seek care in emergency departments for COVID-19 from October-December 2020, compared to whites; Black individuals were 1.4 times more likely. “The COVID-19 pandemic and its disproportional impact on communities of color is just the most recent and glaring example of health inequities that threaten the health of our nation,” CDC Director Rochelle Walensky said in a press briefing on April 12. She added, “We must acknowledge the disparities that exist and commit to an equitable distribution of vaccines, particularly to those communities that have been hardest hit by the virus.” 
  • CDC declares racism a serious public health threat. The CDC on April 9 declared racism a serious public health threat and highlighted the pandemic’s disproportionate and devastating impact on communities of color. “Yet, the disparities seen over the past year were not a result of COVID-19. Instead, the pandemic illuminated inequities that have existed for generations and revealed for all of America a known, but often unaddressed, epidemic impacting public health: racism,” CDC Director Rochelle Walensky said in a statement. “What we know is this: racism is a serious public health threat that directly affects the well-being of millions of Americans. As a result, it affects the health of our entire nation. Racism is not just the discrimination against one group based on the color of their skin or their race or ethnicity, but the structural barriers that impact racial and ethnic groups differently to influence where a person lives, where they work, where their children play, and where they worship and gather in community. These social determinants of health have life-long negative effects on the mental and physical health of individuals in communities of color.” The CDC pledged to continue to study the impact of the social determinants of health and make investments in disproportionately affected communities, among other efforts.
  • Coronavirus variants spread in U.S. The highly contagious B.1.1.7. variant, first identified in the United Kingdom, is now the most common lineage circulating in the U.S., federal health officials said on April 7. To date, 21,000 coronavirus cases in the U.S. have been caused by the B.1.1.7. variant. 
  • COVID-19 linked to increased risk for neurological and psychiatric disorders. A new, large study published in The Lancet Psychiatry found that roughly 1 in 3 COVID-19 survivors experienced a psychiatric or neurological illness six months after being diagnosed with a coronavirus infection. Anxiety and mood disorders were among the most common illnesses recorded, and patients with severe COVID-19 were at greatest risk for developing a psychiatric or neurological condition. “Services need to be configured, and resourced, to deal with this anticipated need,” the study’s authors write. AARP’s Global Council on Brain Health has more information on COVID-19 and brain health
  • Vaccine eligibility wide open by April 19. All American adults, and not just those prioritized based on their risk, should be eligible for a COVID-19 vaccine by April 19, President Joseph Biden said on April 6 at the White House. Biden’s new direction to the states updates his earlier request that they make all U.S. adults eligible for a vaccine by May 1. Biden attributed the ability to move the eligibility date up by two weeks to getting enough vaccine supply, creating more places to get vaccinated and enlisting more people to provide the vaccinations. The administration had already announced that by April 19, 90 percent of all Americans would live within five miles of a vaccination site and 40,000 pharmacies would provide vaccines. 
  • CDC updates guidance on cleaning surfaces. Cleaning surfaces with soap or detergent is enough to prevent the spread of coronavirus in most situations, according to new guidance issued April 5 by the CDC. “Disinfection is only recommended in indoor settings, schools and homes where there has been a suspected or confirmed case of COVID-19, within the last 24 hours,” CDC Director Rochelle Walensky said. People can get infected via contaminated surfaces, Walensky said, but the risk is low. Fogging, fumigation and electrostatic spraying is also not recommended and actually carries safety risks, she said.
  • COVID-19 was the third leading cause of death. The CDCreleased a report March 31 stating that the coronavirus was the third leading underlying cause of death in the United States in 2020, after cancer and heart disease. About 3.4 million deaths occurred in the nation last year and the death rate increased by nearly 16 percent from 2019, according to the report. COVID-19 deaths accounted for about 11 percent of U.S. deaths in 2020.
  • Substance abuse added to the list of conditions that increase risk from COVID-19. The CDC on March 29 streamlined its list of high-risk conditions that put someone at high risk of developing severe COVID-19. The agency also added substance use disorders (such as alcohol, opioid or cocaine use disorder) to the list.
SIME Clinical AI Platform could enable early targeted treatment in  critically ill COVID-19 patients – SIME Clinical AI

What are the Brazil, South Africa and UK variants and will vaccines work?

Covid variant first identified in Brazil have been found in the UK, bringing the total number to 12.

Both – one in the West Midlands and one in Haringey, London – were linked with international travel to Brazil.

Some variants, like this one, appear to be more contagious and there are concerns current vaccines may not work as well.

What are these new variants?

There are many thousands of different versions, or variants, of Covid circulating.

Apart from the Brazil variant (also known as P.1), concerns focus on a few:

It’s not unexpected that new variants have developed – all viruses mutate as they make copies of themselves to spread and thrive.

Most of these differences are inconsequential. A few can even be harmful to the virus’s survival. But some can make it more infectious or threatening.

Are the new ones more dangerous?

There is no evidence that any of them cause much more serious illness for the vast majority of people who become infected.

As with the original version, the risk is highest for people who are elderly or have significant underlying health conditions.

For the UK variant there is some research suggesting it may be associated with a 30% higher risk of death. The evidence is not conclusive, however.

Measures such as washing your hands, keeping your distance from other people and wearing a face covering will still help prevent infections. Because the new variants appear to spread more easily it is important to be extra vigilant.

What’s happening to the virus?

The UK, South Africa and Brazil variants could be much more contagious or easy to catch.

All three have undergone changes to their spike protein – the part of the virus which attaches to human cells.

As a result, they seem to be better at infecting cells and spreading.

Experts think the UK or “Kent” strain emerged in September and may be up to 70% more transmissible or infectious. The latest research by Public Health England puts it between 30% and 50%.

The South Africa variant emerged in October, and has more potentially important changes in the spike protein. Experts recently found a small number of cases of the UK variant that have one of these more concerning changes too.

It involves a key mutation – called E484K – that may help the virus evade parts of the immune system, called antibodies, that can fight coronavirus based on experience from prior infection or a vaccine.

The Brazil variant emerged in July and has this E484K mutation too.

What are variants and how do they happen?

Will vaccines still work?

Current vaccines were designed around earlier versions of coronavirus, but scientists believe they should still work, although perhaps not quite as well.

A recent study suggests the Brazilian variant may be resisting antibodies in people who should have some immunity because they have caught and recovered from an earlier version of coronavirus.

Early lab results, however, suggest the Pfizer vaccine can protect against the new variants, although slightly less effectively.

Two new coronavirus vaccines that could be approved soon – one from Novavax and another from Janssen – appear to offer some protection too.

Data from the Oxford-AstraZeneca vaccine team suggests it protects just as well against the new UK variant. It offers less protection against the South Africa variant – although it should still protect against severe illness.

Early results from Moderna suggest its vaccine is effective against the South Africa variant, although the immune response may not be as strong or long-lasting.

Variants could emerge in the future that are different again.

Even in the worst case scenario, vaccines could be redesigned and tweaked to be a better match – in a matter of weeks or months, if necessary, say experts.

As with flu, where a new shot is given each year to account for any changes in circulating flu viruses, something similar could happen for coronavirus.

What is being done about it?

More variants will emerge.

Scientists around the world are on the look-out and any important ones will be closely studied and monitored.

Experts are updating coronavirus vaccines. The UK Government has announced a deal with biopharmaceutical company CureVac to develop vaccines against future variants, with a pre-order of 50 million doses.

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