Global Statistics

All countries
Updated on July 3, 2022 5:21 am
All countries
Updated on July 3, 2022 5:21 am
All countries
Updated on July 3, 2022 5:21 am

Global Statistics

All countries
Updated on July 3, 2022 5:21 am
All countries
Updated on July 3, 2022 5:21 am
All countries
Updated on July 3, 2022 5:21 am
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Which Covid Vaccine Is Most Effective

Very High Levels Of Protection Against Hospitalization

Which Covid-19 vaccine is most effective?

A recent analysis from PHE looks at how likely people who had an infection with the delta variant were to need treatment in the hospital.

The report puts the protection from requiring hospital treatment for COVID-19 at 71% after one dose and at 92% after two doses of the Oxford-AstraZeneca vaccine. The Pfizer vaccine was 94% effective at preventing hospitalization after the first dose and 96% after two doses.

In India, the Oxford-AstraZeneca COVID-19 vaccine bears the name Covishield.

The report, which has not been peer-reviewed yet, puts these percentages on a par with protection against the alpha variant, or B.1.1.7, which scientists first identified in the U.K.

These findings indicate very high levels of protection against hospitalization with the delta variant with one or two doses of either vaccine, the authors write.

It comes after an earlier report that indicates COVID-19 vaccines were less effective at protecting people from COVID-19 if they had only received the first dose of the Pfizer-BioNTech or Oxford-AstraZeneca vaccines.

However, in the analysis, which has not yet undergone peer review, the researchers measured any symptomatic case of COVID-19, regardless of severity.

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There have been reports of severe allergic reactions to the mRNA vaccines. Both the Pfizer and Moderna vaccines appear, on rare occasions, to;trigger anaphylaxis, a severe and potentially life-threatening reaction. People who develop anaphylaxis must be treated with epinephrine the drug in EpiPens and may need to be hospitalized to ensure their airways remain open. The CDC says people should be monitored for 15 minutes after getting a Covid-19 shot, and 30 minutes if they have a history of severe allergies. J&J recently revealed that a single case of anaphylaxis has been reported in someone who received its vaccine.

It will take time to come up with a firm estimate of how frequently this side effect occurs. The most recent data from the CDC suggest that anaphylaxis occurs at a rate of about 2.5 cases per one million doses given of the Moderna vaccine, and 4.7 cases per million doses of the Pfizer. Many of the people who have developed anaphylaxis have a history of severe allergies and some have had previous episodes of anaphylaxis.

The mRNA vaccines carry a small risk of myocarditis and pericarditis, two types of heart inflammation that are most commonly seen soon after people receive their second shots, health officials have said. Men under 40 seem to be at highest risk, particularly those aged 12 to 17. Most cases reported have been mild and resolved.

Myocarditis And The Covid

Since April 2021, there have been more than a thousand reports of cases of myocarditis and pericarditis happening after receiving the Pfizer-BioNTech or Moderna coronavirus vaccines in the United States, according to the U.S. Centers for Disease Control and Prevention .

Considering the hundreds of millions of COVID-19 vaccine doses that have been administered, these reports are very rare. The problem occurs more often in adolescents and young adults, and in males. The myocarditis or pericarditis in most cases is mild and resolves quickly.

Seek medical attention right away if, within a few days of receiving the second injection of an mRNA COVID-19 vaccination , you or your child experiences chest pain, shortness of breath, or feelings of having a fast-beating, fluttering, or pounding heartbeat.

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Astrazeneca And Oxford Vaccine

The AZD1222 vaccine also uses the coronavirus S protein gene in an inactivated virus to stimulate the immune system. Based on its U.S. phase III clinical trial, the vaccine is 76% effective.

The U.K. authorized the vaccine for emergency use based on prior phase III trials in the U.K. and other countries. Dozens of other countries are also administering the AstraZeneca vaccine, but the U.S. has not authorized it for emergency use. Similar to the Janssen/J&J COVID-19 vaccine, there is a link between life-threatening blood clots occurring within two weeks of AZD1222 vaccination, as reported by the European Medicines Agency . This adverse event is very rare, but some cases have been fatal.

The AstraZeneca/Oxford vaccine only requires refrigeration for storage and costs less than other vaccines.

How Do The Vaccines Work

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The United States has authorized three vaccines for emergency use, and a fourth is likely to go before the Food and Drug Administration for approval in the coming weeks.

Pfizer and Moderna: The first two COVID-19 vaccines to be greenlit in the United States use messenger RNA , which is a molecule that instructs human cells to make a piece of the spike protein that the coronavirus uses to attach to and infect human cells. The material from the vaccine quickly disintegrates and never enters the cells nucleus, so it cant alter the recipients DNA. The presence of the harmless spike proteins triggers the immune system to create antibodies and activate T-cells that mount an immune response. With the immune system primed, it is ready to act quickly if it ever detects the coronavirus in the body.

Researchers have been working on mRNA technology since the 1990s to fight a variety of diseases from influenza to Ebola, but the COVID-19 vaccine is the first time this technology has been authorized for the public.

The Pfizer vaccine requires two doses administered 21 days apart and the Moderna vaccine requires two doses 28 days apart.

Its kind of like hijacking a known virus, says Wilbur Chen, MD, an infectious disease and vaccine expert and chief of the adult clinical studies section of the Center for Vaccine Development and Global Health within the University of Maryland School of Medicine.

The Johnson & Johnson vaccine requires only one dose.

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Natural Immunity And One Vaccination May Offer Best Protection

The analysis indicated that people who had never had the infection and received a vaccine in January or February of 2021 were up to 13 times more likely to contract the virus than people who had already had the infection.

The researchers also compared reinfection rates among people who had once had a confirmed SARS-CoV-2 infection and were still unvaccinated and people who had once had the infection and had also received one dose of the Pfizer-BioNTech vaccine.

Results showed that the unvaccinated group was twice as likely to contract the infection again, compared with those who had received one dose of the vaccine.

The findings appear to indicate increased protection from natural immunity over vaccine-conferred immunity. This may be due to a more extensive immune response to the SARS-CoV-2 proteins, compared with the immune activation provided by the vaccine, the researchers suggest.

Infection disease experts warn that the findings should not be viewed as an excuse to forego vaccination. In an interview with MNT, Dr. William Schaffner, a professor of infectious diseases at Vanderbilt University Medical Center, in Nashville, TN, said that the vaccines are doing exactly what they were designed to do.

All the vaccines we have, Moderna, Pfizer, and , are very effective in preventing hospitalization a severity of illness that requires admission to the hospital.

Do I Need The Vaccine If I Have Already Had Covid

Even if you had COVID-19, the CDC still recommends getting vaccinated. Thats because experts do not yet know how long you are protected from getting sick again after recovering from COVID-19. Even if you have already recovered from COVID-19, it is possible although rare that you could be infected with the virus that causes COVID-19 again, the agency explains.

Have questions? Talk to your doctor.

Essentially, what a vaccine is doing is teaching the immune system how to handle something before you actually encounter the real thing so that, hopefully, when you do encounter the real thing, youre able to deal with it quickly and get rid of it.

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How Long Does Immunity Last After Vaccination

There is currently no reliable test to indicate how long immunity lasts after any of the vaccines. The only clue we can get is to look at immunity conferred by the virus itself, with various studies suggesting it lasts several months. One study last

Reinfection has also ;so far ;been relatively rare and a UK study of 20,000 health workers;in January showed;that immune responses from past infection reduce the risk of catching the virus again by 83 per cent for at least five months.

However, immunity against other coronaviruses – such as the common cold – wanes over time so booster shots are likely to be needed as most experts believe this virus is not going away. The emergency of new variants may also make further jabs necessary, and the UK is now actively investigating this area.;

Pfizer And Biontech Confirm High Efficacy And No Serious Safety Concerns Through Up To Six Months Following Second Dose In Updated Topline Analysis Of Landmark Covid

Connecticut Governor Hails Pfizer’s Covid Vaccine as ‘Most Effective’ Ever
  • Analysis of 927 confirmed symptomatic cases of COVID-19 demonstrates BNT162b2 is highly effective with 91.3% vaccine efficacy observed against COVID-19, measured seven days through up to six months after the second dose
  • Vaccine was 100% effective in preventing severe disease as defined by the U.S. Centers for Disease Control and Prevention and 95.3% effective in preventing severe disease as defined by the U.S. Food and Drug Administration
  • Vaccine was 100% effective in preventing COVID-19 cases in South Africa, where the B.1.351 lineage is prevalent
  • Vaccine safety now evaluated in more than 44,000 participants 16 years of age and older, with more than 12,000 vaccinated participants having at least six months follow-up after their second dose
  • The companies plan to share these results with worldwide regulatory agencies soon

This press release features multimedia. View the full release here:

These data confirm the favorable efficacy and safety profile of our vaccine and position us to submit a Biologics License Application to the U.S. FDA, said Albert Bourla, Chairman and Chief Executive Officer, Pfizer. The high vaccine efficacy observed through up to six months following a second dose and against the variant prevalent in South Africa provides further confidence in our vaccines overall effectiveness.

About the Analysis


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Number Of Doses/amounts Of Vaccine Per Dose

Both the Moderna and the Pfizer vaccines require two shots: a priming dose, followed by a booster shot. The interval between Moderna doses is 28 days; for the Pfizer vaccine, its 21 days.

Each dose of Pfizers contains 30 micrograms of vaccine. Moderna went with a much larger dose of vaccine, 100 micrograms. It means the company is using a little more than three times as much vaccine per person as Pfizer is. And yet, they arent getting better results. The governments vaccine development program, formerly called Operation Warp Speed, has asked Moderna to test if it could lower the dosage of its vaccine without eroding the vaccines protection.

The J&J vaccine is, as mentioned, a single-dose vaccine. The company is also testing a two-dose regimen, with the two shots given eight weeks apart. The results from that 30,000-person trial arent expected until sometime in May.

J&J is also testing what happens to antibody responses when a person who received the single dose regimen receives a small booster shot quite a bit later, Johan Van Hoof, managing director of Janssen Vaccines revealed recently. Van Hoof didnt say how long the interval is between the single shot and the small booster, nor did he say when J&J expects results from that study.

What Is The Outlook For People Who Have Cerebral Venous Sinus Thrombosis

CVST is a rare but potentially serious condition. Around 80% of people make a strong recovery, though some will continue to experience headache, vision problems, impaired motor control, speech problems, or other mild symptoms for weeks or months. For some, these symptoms may be permanent.

In general, the best outcomes are associated with early diagnosis and treatment. CVST recurs in about 2% to 4% of cases, and people who have experienced CVST are at increased risk for venous thromboembolism elsewhere in the body.

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This Story Is Part Of A Group Of Stories Called

Evidence-based explanations of the coronavirus crisis, from how it started to how it might end to how to protect yourself and others.

The Covid-19 pandemic has changed, and with it, so has the effectiveness of the vaccines.

The bottom line remains the same: The mRNA vaccines from Pfizer/BioNTech and Moderna that are most prevalent in the US are still quite effective in preventing any illness from the novel coronavirus, and extremely effective in preventing the kind of severe illness that leads to hospitalization and death. On Wednesday, the Centers for Disease Control and Prevention confirmed those basic facts with its most robust data yet.

But the statistics that were widely publicized when those vaccines were first approved in December the ones that showed vaccines were 95 percent effective in preventing all illness and 100 percent effective in stopping hospitalization or death are now thoroughly out of date. The risk that a vaccinated person would experience symptoms if they contract Covid-19 is higher than it was back then, even if it is still significantly lower than if the person were unvaccinated. The now-dominant delta variant is likely to blame.

So exactly how effective are the vaccines against this new, more dangerous iteration of the virus? And how long does immunity provided by the vaccines actually last?


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How The Moderna Astrazeneca Pfizer And Other Covid Vaccines Compare

The UK has approved four Covid vaccines with one more set to come soon from effectiveness to ease of use, how do they compare?

Comparing vaccines head-to-head is tricky, but as more;Covid-19 jabs become available ;in the UK at least ;it is also human nature.;

The problem is that none have been tested in this way, although new jabs coming down the line will now have to prove they work at least as well as the existing vaccines before they are approved for use.;

However, as vaccination campaigns;gather pace;around the world, it is becoming;possible to get a clearer idea of the real-world effectiveness of the jabs, as well as which are more appropriate for certain populations and settings.;

As of May 28, 38,614,683 people in the UK have received a first dose of the vaccine, while 24,043,956 of the most clinically vulnerable are now fully inoculated.;

The key message, though, remains that all of the available vaccines provide effective protection against coronavirus infection, and even better protection against serious illness and disease. As such, the advice remains to get any jab you are offered.;;

But there are differences between them. So, how do the jabs compare?

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Unlike the Pfizer and Moderna shots, the J&J vaccine uses a cold virus, called an adenovirus, to carry the spike gene into the body. J&J uses a human adenovirus to create its vaccine while a similar vaccine not yet approved in the U.S., AstraZeneca, uses a chimpanzee version.

J&Js shot uses a cold virus like a Trojan horse to carry the spike gene into the body, where cells make harmless copies of the protein to prime the immune system in case the real virus comes along. Its the same technology the company used in making an Ebola vaccine.

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Pfizer Says Covid Vaccine Is Highly Effective Against Delta Variant

A person walks past a Pfizer logo amid the coronavirus disease pandemic in the Manhattan borough of New York City, New York, U.S., April 1, 2021. REUTERS/Carlo Allegri

JERUSALEM, June 24 – The Pfizer-BioNTech >PFE.N< vaccine is highly effective against the Delta variant of COVID-19, a Pfizer official in Israel said on Thursday.

First identified in India, Delta is becoming the globally dominant variant of the coronavirus, according to the World Health Organization.

“The data we have today, accumulating from research we are conducting at the lab and including data from those places where the Indian variant, Delta, has replaced the British variant as the common variant, point to our vaccine being very effective, around 90%, in preventing the coronavirus disease, COVID-19,” Alon Rappaport, Pfizer’s medical director in Israel, told local broadcaster Army Radio.

A study by researchers from the University of Texas together with Pfizer and BioNtech and published this month by Nature journal found that antibodies elicited by the vaccine were still able to neutralize all tested variants, including Delta, albeit at reduced strength.

“We continue to synthesize viruses in our labs and with collaborators as we see new variants emerge so we can conduct testing to obtain the most information we can about our vaccines impact on neutralisation of emerging strains,” a Pfizer spokesperson said in an email to Reuters.

Which Vaccines Has The Uk Ordered

WATCH: Which COVID vaccine is most effective?

The UK has ordered vaccines from:

  • GSK/Sanofi
  • Valneva

The Pfizer, Oxford/AstraZeneca and Moderna vaccines are currently in use in the UK, and the government announced on May 28 that 20 million doses of;J&J have now been ordered. Additionally, Novavax has published phase three data and looks set to be approved soon. The GSK/Sanofi and Valneva jabs are still in development.;

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