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CDC says 28 blood clot instances, three deaths could also be linked to J&J Covid vaccine

CDC says 28 blood clot cases, 3 deaths may be linked to J&J Covid vaccine

The Johnson & Johnson Janssen vaccine

Stephen Zenner | LightRocket | Getty Images

CDC scientists say their investigation into a rare blood clotting problem related to the Johnson & Johnson Covid-19 vaccine identified 28 people who may have developed life-threatening blockages – three of whom have died.

The Food and Drug Administration and Centers for Disease Control and Prevention urged states on April 13 to temporarily cease use of J & J’s vaccine “out of caution” while examining six women ages 18 to 48 who developed cerebral venous sinus thrombosis, or CVST combined with low platelets within about two weeks of receiving the shot.

They recommended resuming use of the shot 10 days later after the CDC found the benefits of the vaccinations outweighed their risks.

CVST is a form of thrombosis with thrombocytopenia, or TTS, which are blood clots with a low platelet count that make patients at risk of stroke. Platelets actually help the blood to clot.

CDC official Dr. Tom Shimabukuro said Wednesday that four of the 28 people with TTS were hospitalized on May 7, one of whom was in intensive care, and two were being discharged to a post-acute care facility. The remaining 19 patients have all been discharged, he said during a presentation to the CDC Advisory Committee on Immunization Practices. The panel voted earlier in the day to recommend the Pfizer BioNTech vaccine for 12 to 15 year olds.

The mean age of the patients with TTS was 40 years and ranged from 18 to 59 years. Women aged 30 to 39 were the greatest risk group. All patients received the J&J shot before the April 13 break. Of the 28 TTS cases, 19 involved the brain, with 10 of those patients suffering from cerebral haemorrhage, Shimabukuro said.

The other clots formed in the lower extremities, pulmonary arteries, or other areas of the body.

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C.D.C Confirms Extra Instances of Uncommon Blood Clot Dysfunction Linked to J.&J. Vaccine

C.D.C Confirms More Cases of Rare Blood Clot Disorder Linked to J.&J. Vaccine

Federal health officials have now confirmed 28 cases, including six in men, of a rare bleeding disorder in adults who have received the Johnson & Johnson Covid-19 vaccine.

Dr. Tom Shimabukuro, deputy director of the vaccination safety bureau at the Centers for Disease Control and Prevention, presented the new cases on Wednesday at a CDC advisory board meeting

The number is an increase from the 15 confirmed cases that were all women reported at the meeting last month.

Although officials have now identified a handful of cases in men, women – particularly between the ages of 30 and 49 – appear to be at increased risk. “The trend is that women in all age groups have higher reporting rates than men,” said Dr. Shimabukuro at the meeting.

Patients with the rare but serious disorder develop blood clots, often in the brain, as well as low levels of platelets, components of the blood that promote clotting. The disorder is a “rare, clinically serious, and potentially life-threatening condition,” said Dr. Shimabukuro.

Last month, after reports first emerged that six women who had received the vaccine had developed the disorder, federal health officials recommended discontinuing use of the vaccine during the investigation. They lifted the suspension 10 days later and warned the vaccine label of possible risks that suggest that there is a “plausible” link between the vaccine and the disease.

22 of the confirmed cases so far involved women and six men. All were adults between the ages of 18 and 59 who received the vaccine before the national break. (Another case was also recorded in a 25-year-old male who participated in the clinical trial.)

Three people have died and four remain in the hospital, including one in intensive care. No new deaths have been documented since last month’s meeting, said Dr. Shimabukuro.

The overall risk remains extremely low. More than 9 million doses of the Johnson & Johnson vaccine have now been administered in the United States.

There were 12.4 cases per million doses in women between 30 and 39 years of age and 9.4 cases per million doses in women between 40 and 49 years of age, the two demographics that appear to be at greatest risk. There were fewer than 3 cases per million doses in older women and men of all ages.

Of the 28 confirmed cases, 12 people who developed the disorder had obesity, 7 had high blood pressure, 3 had diabetes, and 3 were taking estrogen, although it is not yet clear whether any of these factors could significantly increase the risk of the disorder.

Officials will continue to look for cases of the coagulation disorder in vaccinated people, said Dr. Shimabukuro.

There were no confirmed cases of coagulation disorder after the Pfizer BioNTech or Moderna vaccines, which use a different technology, said Dr. Shimabukuro.

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Public demand for AstraZeneca vaccine falls after blood clot scares

Ireland, Netherlands suspend AstraZeneca vaccine amid blood clot fears

A medical worker fills a syringe with AstraZeneca vaccine at Santa Caterina da Siena – Amendola secondary school in Salerno on March 13, 2021 in Salerno, Italy.

Francesco Pecoraro | Getty Images News | Getty Images

LONDON – Public preference for the coronavirus vaccine developed by AstraZeneca and the University of Oxford has fallen since reports surfaced suggesting it may be linked to some cases of unusual blood clotting events.

An April study of nearly 5,000 adults in the UK, with Covid vaccine uptake high and the vaccination program well established, found that public preference for the AstraZeneca Covid vaccine has declined since March and there is a belief that that he caused blood clots to have increased.

The UK academic study found that 17% of the public now say they would prefer the AstraZeneca vaccine if given a choice – up from 24% towards the end of March.

And 23% of people now believe the AstraZeneca vaccine causes blood clots – up from 13% in March. However, the public are still the most likely to say that this claim is false (39%) or that they don’t know if it is true (38%).

The study, conducted April 1–16 by the University of Bristol, King’s College London, and the NIHR Health Protection Unit for Emergency Preparedness and Relief, found a “big difference” in beliefs before and after MHRA ( the UK Medicines Agency) announced on April 7th that there is a possible link between the vaccine and extremely rare blood clots.

The study found that 17% of respondents in the first week of this month thought this claim was true, compared with 31% who were asked about it.

Why autumn

Since the first clinical data was published, the vaccine has shown an average effectiveness rate of 70% (subsequent studies in the US have shown an effectiveness rate of 79%, and other studies have shown that the effectiveness rate increases with a larger gap between the first and second doses ) The fate of the AstraZeneca vaccine is mixed to say the least.

Continue reading: Dates, Doubts, and Disputes: A Timeline for AstraZeneca’s Covid Vaccine Problems

One of the recent hurdles for the AstraZeneca vaccine was a small number of reports of unusual, sometimes fatal, blood coagulation events that occurred in post-vaccinating people in Europe in February, causing several countries to suspend use of the vaccine.

The UK and EU drug regulators (the UK Medicines and Health Products Regulatory Authority and the European Medicines Agency) examined the reports and said that while there is a possible link between the vaccine and low incidence of blood clotting, the benefits of the vaccine are significant outweighing them Risks.

The Anglo-Swedish vaccine maker, British government and experts largely defended the vaccine, saying it protected millions of people by reducing Covid cases, hospitalizations and deaths.

In addition, experts tried to correlate the risk, saying the number of reported rare blood clotting cases with low platelets was about one case in 250,000 people vaccinated and one death in one million.

Britain is fortunate that it has traditionally received high levels of public support for vaccination. The vaccine preference survey found that, despite the growing belief that it was associated with blood clots, the AstraZeneca vaccine did not affect general confidence in vaccines in general. 81% say vaccines are safe, compared to 73% who said so in late 2020.

Similarly, views on how well vaccines work have changed: 86% say they are effective, up from 79% in November and December 2020.

However, surveys have shown that the public perception of the AstraZeneca vaccine has deteriorated in mainland Europe, and there is scattered evidence that people in the EU are using the AstraZeneca vaccine (referred to as the “Aldi” vaccine after the low-cost food chain will) because in favor of the coronavirus vaccine from Pfizer-BioNTech, which also prevails when EU vaccinations are introduced.

Continue reading: “The damage is done”: Europe’s caution against the AstraZeneca vaccine could have far-reaching consequences

Moderna’s shot and Johnson & Johnson’s shot have also been approved for use in the EU and the UK, but have been less widely used, EU vaccination data show.

Hesitation to vaccinate can apparently work both ways. A British doctor reported in the Evening Standard newspaper in January that some of his patients had turned down the opportunity to receive the Pfizer vaccine, saying they would “wait for the English one.”

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CDC panel debates J&J Covid vaccine after uncommon blood clot challenge

CDC panel debates J&J Covid vaccine after rare blood clot issue

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An advisory panel from the Centers for Disease Control and Prevention is holding an emergency meeting Friday to discuss Johnson & Johnson’s Covid-19 vaccine and its use after six women developed a rare but potentially life-threatening bleeding disorder called the one left dead.

A positive recommendation from the CDC Advisory Committee on Immunization Practices could pave the way for US regulators to lift the recommended hiatus for the use of the J&J shot earlier this weekend.

The CDC panel decided to postpone a decision on the vaccine last week while officials continued to investigate cases of six women who developed cerebral sinus thrombosis (CVST) within about two weeks of receiving the shot.

Earlier this week, J&J announced that it would restart its vaccine rollout in Europe after regulators there backed the single vaccine by recommending adding a warning to the label. The European Medicines Agency has examined all available evidence, including reports from the United States.

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A C.D.C. panel discusses new uncommon clot circumstances in J. & J. shot recipients and the way total threat appears to be very low.

A C.D.C. panel discusses new rare clot cases in J. & J. shot recipients and how overall risk seems to be very low.

Twelve of the 15 women in the confirmed cases developed blood clots in the brain. Many had blood clots elsewhere as well. Initial symptoms, which include a headache, usually begin six or more days after vaccination, said Dr. Shimabukuro. As the disorder develops, it can cause increased headaches, nausea and vomiting, abdominal pain, weakness in one side of the body, difficulty speaking, loss of consciousness, and seizures.

Dr. Shimabukuro found that seven of the women were obese, two had hypothyroidism, two had high blood pressure, and two were using oral contraceptives. It is not yet clear whether any of these factors could increase the risk of developing a coagulation disorder after vaccination.

Patients’ symptoms closely resemble a rare syndrome that can be caused by heparin, a widely used blood thinner, said Dr. Michael Streiff, a hematologist at Johns Hopkins University, joined the panel. Heparin, which could typically be used to treat blood clots, shouldn’t be used to treat these patients, he said.

Doctors should consider the rare coagulation disorder in patients who have blood clots and low platelet counts within three weeks of receiving the Johnson & Johnson vaccine, said Dr. Streiff.

“Knowing that this syndrome exists will help improve outcomes,” he said.

The committee could recommend Johnson & Johnson put up a formal warning label about the side effects, as the company has done in the European Union. About 10 million doses or more of the vaccine, which is manufactured at the company’s facility in the Netherlands, are on shelves in the United States and could be used immediately.

The meeting comes as the federal government is also investigating issues at a Baltimore factory that is slated to meet the country’s demand. Emergent BioSolutions, the operator of the facility, has manufactured tens of millions of doses of Johnson & Johnson’s vaccine, but they cannot be distributed until regulatory agencies certify the facility.

After Emergent had to discard up to 15 million potentially contaminated doses of the vaccine last month, federal regulators conducted an inspection that found a number of problems, including the risk of other lots being contaminated.

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‘We Had been Flying Blind’: A Dr.’s Account of a Lady’s J.&J. Vaccine-Associated Blood Clot Case

‘We Were Flying Blind’: A Dr.’s Account of a Woman’s J.&J. Vaccine-Related Blood Clot Case

Dr. Lipman said when the team examined her blood samples the pieces started to fit and they discovered that she appeared to have the same problem that they knew had occurred in the UK and Europe after patients took the AstraZeneca Received the vaccine. mostly in young women. They switched from heparin to another blood thinner and followed instructions from doctors in the UK who had treated AstraZeneca recipients with a similar disorder.

Hoping for more information about the condition and a possible association with the Johnson & Johnson vaccine, Dr. Lipman to call the Food and Drug Administration for an emergency number. It was a weekend and he said the person who answered told him that there was no one available to help and that the line should be kept open for emergencies.

“I thought this was an emergency,” said Dr. Lipman. “She hang up.”

He called back to ask how to contact Janssen, who makes the Johnson & Johnson vaccine. That information was not available, and he said the person who responded also told him that the FDA was unable to provide advice on patient care.

An FDA spokeswoman, Stephanie Caccomo, said in an email, “We will continue to investigate to ensure doctors who ask for help from the FDA are getting the help they are looking for.”

Dr. Lipman said the pharmacist at his hospital filed an online report with the Centers for Disease Control and Prevention in early April, but the agency didn’t contact him until this week to inquire about the case. The agency declined to comment on whether they were with Dr. Lipman had communicated, a spokeswoman, Kristen Nordlund, said via email.

At a CDC advisory board meeting on Wednesday, Johnson & Johnson and Dr. Tom Shimabukuro, an agency security expert, shared data on the young woman in Nevada. Following the meeting, Nevada officials issued a statement saying the meeting was the first time they had heard of a case in their state – they had previously informed the public that no cases had been reported – and they asked “federal partners” why the state had not been informed.

At the Nevada hospital, an interventional radiologist inserted a tube through blood vessels into the young woman’s brain and suctioned out the clots with a device. More clots later formed and he performed the procedure again.

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Panicked sufferers name medical doctors as Covid vaccine hesitancy rises with J&J blood clot challenge

Panicked patients call doctors as Covid vaccine hesitancy rises with J&J blood clot issue

More Americans are likely to refuse to receive the Covid-19 vaccine from Johnson & Johnson after U.S. health officials said six women developed a rare bleeding disorder with one dead and another in critical condition, experts said for public health and vaccines using CNBC on Tuesday.

The Food and Drug Administration asked states early Tuesday to temporarily stop using J & J’s single-shot vaccine “out of caution” after six women aged 18 to 48 out of the roughly 6.9 million people who received the shot developed blood. A coagulation disorder known as cerebral venous sinus thrombosis, or CVST.

All women developed the condition that occurs when a blood clot forms in the venous sinuses of the brain that prevents blood from flowing back to the heart within about two weeks of receiving the shot from the brain, health officials told reporters on a phone call .

“People who have recently received the vaccine in the past few weeks should be aware if they are looking for symptoms,” said Dr. Anne Schuchat, the deputy chief director of the Centers for Disease Control and Prevention, during a press conference on Tuesday. “If you have received the vaccine and have severe headache, stomach pain, leg pain, or shortness of breath, you should contact your doctor and see a doctor.”

Shortly after the FDA issued the warning, more than a dozen states, as well as some pharmacies, took steps to stop vaccination with J & J’s vaccine. Some replaced scheduled appointments with either the Pfizer or Moderna vaccine. Some doctors say they are already taking calls from worried patients.

People were already skeptical of vaccines before the coronavirus emerged as a new pathogen in China in December 2019, infecting more than 31.2 million Americans and killing at least 562,718 people in just over a year. Warning from U.S. health officials to states is likely to be even more reluctant to take J & J’s shot and the other vaccines, and threatens to hold back the nation’s recovery from the pandemic, health experts told CNBC.

“Unfortunately, this is likely to exacerbate those who are a little hesitant about getting a vaccine,” said Isaac Bogoch, an infectious disease specialist who served on several drug data and safety oversight panels. “Senior public health officials need to continue to be open, honest, transparent, and most importantly, contextualize that this is a low risk.”

According to Dr. Anthony Fauci, President Joe Biden’s chief medical officer, the goal is to vaccinate between 70% and 85% of the US population – or about 232 to 281 million people – to achieve herd immunity and suppress the pandemic.

To date, more than 120 million Americans, or 36% of the total US population, have received at least one dose of a Covid-19 vaccine, according to the CDC. Around 74 million Americans, or 22% of the total US population, are fully vaccinated, according to the CDC. Children under the age of 16 are not yet eligible to shoot in the United States, and some adults are likely to refuse to get a vaccine.

“This puts a wrench in the plans. It will slow down the rollout,” said Dr. Jeffrey Kahn, director of the Berman Institute of Bioethics at Johns Hopkins University. “People will say, ‘I don’t want this, I want one of the others who don’t have this problem,’ even if it’s an extremely rare occurrence.”

Some Americans, especially in black, Hispanic, and rural communities, have already been reluctant to get the J&J vaccine, especially because they found it to be worse than Pfizer and Moderna’s. The highly effective J&J shot, especially against serious illnesses, showed 72% effectiveness in protecting against Covid in the US about a month after inoculation. This is comparable to the effectiveness of Pfizer and Moderna vaccines with two doses of around 95%.

Single-dose vaccines like J & Js were critical to “getting into communities where a two-dose regimen was impractical or even possible,” Kahn said. US health officials used J & J’s vaccine primarily to reach poorer urban and rural areas where residents could not easily get to a vaccination clinic or did not have reliable internet access.

“These communities are also the hardest hit by Covid,” said Kahn. “Interrupting Use of J & J. [is] one stroke to do that effectively and quickly. “

Dr. Stephen Schrantz, who was part of the team leading a J&J vaccine study at the University of Chicago Medicine, said he already had patients who didn’t want the J&J vaccine and said the news would give them more evidence give to say, “See, I told you.”

“I suspect that vaccine adoption and uptake will slow down, there will be a move away from the J&J vaccine even if the CDC and FDA conclude that there is no causal link,” he said. “And as the wearing of masks wears off, there may be more cases like we have in Michigan.”

Dr. Scott Gottlieb, who sits on Pfizer’s board of directors, predicted the move will fuel “the reluctance” of some people to get a Covid vaccine.

“Even if there is no causal link, even if it is extremely rare, we will see that the whole conversation is now ignited on social media,” he told CNBC in an interview.

Dr. Purvi Parikh, an infectious disease allergy and immunology specialist at NYU Langone Health, described the FDA warning Tuesday as a “double-edged sword” and said it would likely raise concerns for already reluctant Americans. She also said she had already received “panic calls” from her own patients about the J&J vaccine.

“But if anything, I would like to repeat again: This only gives me more confidence in our system because these security checks work. Hopefully it will give some people peace of mind,” she added on “Squawk on the Street”. “” “Again, to look at the bigger picture, the benefits still far outweigh the risks of this vaccination.”

Dr. Archana Chatterjee, pediatric infectious disease specialist and member of the FDA’s Advisory Committee on Vaccines and Related Biological Products, echoed Parikh’s remark. She added that there is nothing “unusual” in the way US health officials are addressing the problem.

“This is a normal procedure that occurs,” she said.

“But of course whenever a serious adverse event is reported about a vaccine that raises public concern,” she added. “If you talk about vaccine trust or vaccine reluctance, could it have an impact? It certainly is possible.”

Dr. Paul Offit, another member of the Advisory Committee on Vaccines and Allied Biological Products, hopes Americans will be “rational” about the problem, adding that cases of blood clots seem extremely rare. He noted that convincing people in hard-to-reach communities could be a challenge.

“It should be reassuring to the people that the officials are still looking [at the vaccine], even for rare side effects, “he said.

– CNBC’s Kevin Stankiewicz contributed to this article.

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Eire, Netherlands droop AstraZeneca vaccine amid blood clot fears

Ireland, Netherlands suspend AstraZeneca vaccine amid blood clot fears

A medical worker fills a syringe with AstraZeneca vaccine at Santa Caterina da Siena – Amendola secondary school in Salerno on March 13, 2021 in Salerno, Italy.

Francesco Pecoraro | Getty Images News | Getty Images

LONDON – Ireland and the Netherlands have joined the growing list of countries that have stopped using the coronavirus vaccine developed by AstraZeneca and Oxford University because of blood clot concerns.

The Dutch government said Sunday that the Oxford-AstraZeneca vaccine would not be used until March 29, while Ireland said earlier in the day it had temporarily suspended the shot as a precautionary measure.

The World Health Organization tried to downplay the ongoing safety concerns and stated last week that there was no link between the shot and an increased risk of developing blood clots. The United Nations Health Department has urged countries to continue using the Oxford-AstraZeneca vaccine.

Even so, some European countries have already stopped using the Oxford-AstraZeneca vaccine. It added to the worries of the battered vaccination campaign in the region when the German health department warned that a third wave of coronavirus infections had already begun.

Thailand has also stopped the planned use of the vaccine.

The move to suspend use by Dutch and Irish officials came shortly after the Norwegian Medicines Agency announced that three health workers were hospitalized for bleeding, blood clots and low platelet counts after receiving the Oxford-AstraZeneca vaccine. Norway has suspended its vaccination program against Oxford-AstraZeneca.

Geir Bukholm, director of the Infection Control and Environmental Health Department at the Norwegian Public Health Institute, said the Norwegian Medicines Agency will “follow up on these suspected side effects and take the necessary action in this serious situation”.

The picture taken on November 27, 2020 shows “Nikki” Anniken Hars treating a Covid-19 patient in the intensive care unit of Oslo University Hospital Rikshospitalet in Oslo, Norway.

JIL YNGLAND | AFP | Getty Images

The European Medicines Agency, the European Medicines Agency, also said there is no evidence that Oxford-AstraZeneca’s vaccine causes blood clots and that the vaccine’s benefits “continue to outweigh the risks”.

The EMA admitted that some European countries had stopped using the Oxford-AstraZeneca shot, but said vaccinations may continue to be given while a clot investigation is ongoing.

How did AstraZeneca react?

“A careful review of all available safety data from more than 17 million people vaccinated with the AstraZeneca COVID-19 vaccine in the European Union (EU) and the UK found no evidence of an increased risk of pulmonary embolism, deep vein thrombosis ( DVT) or thrombocytopenia in a certain age group, gender, group or country, “AstraZeneca said in a statement on Sunday.

The most common side effects of the Oxford AstraZeneca vaccine, which does not contain the virus and cannot cause Covid, are usually mild or moderate and improve within a few days after vaccination.

A health worker holds a box of the AstraZeneneca vaccine at the Bamrasnaradura Institute for Infectious Diseases in Nonthaburi Province on the outskirts of Bangkok.

Chaiwat subprasome | SOPA pictures | LightRocket via Getty Images

The pharmaceutical company said that 15 events involving deep vein thrombosis and 22 events involving pulmonary embolism were reported among those vaccinated in the EU and the United Kingdom.

“This is much less than expected to occur naturally in a general population of this size, and it is similar to other approved COVID-19 vaccines,” said AstraZeneca.

What do the experts say?

“Covid definitely causes bleeding disorders and each of the vaccines prevents Covid disease, including more severe cases,” said Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine.

“Therefore, it is highly likely that the vaccine’s benefits will significantly outweigh the risk of clotting disorders, and the vaccine will prevent other consequences of Covid, including deaths from other causes.”

Evans said it was “perfectly reasonable” to conduct studies on vaccines and coagulation disorders, but added, “It seems a step too far to take precautionary measures that would prevent people from receiving vaccines that prevent disease.”

Many high-income countries – such as the UK, France, Australia and Canada – have decided to continue rolling out the Oxford-AstraZeneca vaccine.

“When there is clear evidence of serious or life-threatening side effects that have important consequences,” Adam Finn, professor of pediatrics at Bristol University, said in a statement.

“So far, however, this has not been the case, and it is highly undesirable to disrupt a complex and urgent program every time people, after receiving a vaccine, develop illnesses that are random and not causal. In situations like this, it is not easy to Making the right call, but a steady hand on the tiller is probably what is needed most, “said Finn.

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AstraZeneca Covid vaccine suspended in some international locations over blood clot fears

AstraZeneca Covid vaccine suspended in some countries over blood clot fears

A health worker holds a box of the AstraZeneneca vaccine at the Bamrasnaradura Institute for Infectious Diseases in Nonthaburi Province on the outskirts of Bangkok.

Chaiwat subprasome | SOPA pictures | LightRocket via Getty Images

LONDON – The coronavirus vaccine developed by AstraZeneca and Oxford University has been exposed in a number of countries in Europe and Asia after reports of blood clots in some vaccinated people.

However, many other nations have defended their use of the shot and announced that they will continue their respective vaccination campaigns.

Thailand became the first Asian country to stop using the sting on Friday due to safety concerns, shortly after Denmark announced a two-week hiatus from its nationwide rollout after reports of blood clots and a death.

In a setback to the battered vaccination campaign in Europe, seven other countries have also suspended the use of the Oxford-AstraZeneca shot: Norway, Iceland, Bulgaria, Luxembourg, Estonia, Lithuania and Latvia.

Austria and Italy have since announced that they will no longer use certain batches of the vaccine as a precaution.

The European Medicines Agency, the European Medicines Agency, stressed Thursday that there was no evidence that the shot was causing blood clots, adding that the vaccine’s benefits “continue to outweigh the risks”.

The EMA acknowledged that some member states had stopped using the Oxford-AstraZeneca shot, but said vaccinations may continue to be given while a clot investigation is ongoing.

By Wednesday, around 5 million people in Europe had received the Oxford-AstraZeneca vaccine. Of this number, 30 cases of so-called “thromboembolic events” were reported. These cases relate to blood clots that form in the blood vessels and block blood flow.

AstraZeneca said the vaccine has been extensively studied in Phase 3 trials and peer-reviewed data confirms the shot is “generally well tolerated.”

Why do countries pause vaccination campaigns?

The Thai Ministry of Health announced on Friday that it would temporarily postpone the use of the Oxford-AstraZeneca vaccine. The shot is reportedly labeled a “good vaccine” but is said to be suspended for safety investigation.

Kiattiphum Wongjit, permanent secretary of the health ministry, said the Southeast Asian country may suspend its vaccination campaign as it has largely controlled a second wave of Covid cases through quarantines and border controls, according to Reuters.

A press conference will be held on March 12, 2021 in Bangkok, Thailand, to temporarily suspend the introduction of vaccination against AstraZeneca Covid-19 in Thailand.

Xinhua | Rachen Sageamsak via Getty Images

The country of nearly 70 million people has so far recorded around 26,600 cases and 85 deaths, according to Johns Hopkins University.

The decision of Thailand to suspend the planned launch of the Oxford-AstraZeneca vaccine, which was due to start on Friday, was made following the decision of the Danish health authority.

“It is important to emphasize that we have not decided against the AstraZeneca vaccine, but are putting it on hold,” said Soren Brostrom, director of the National Health Agency in Denmark, on Thursday.

“There is good evidence that the vaccine is both safe and effective. However, we and the Danish Medicines Agency need to respond to reports of possible serious side effects from both Denmark and other European countries.”

Many high-income countries have chosen to continue rolling out the Oxford-AstraZeneca vaccine for safety reasons.

The UK, France, Australia, Canada and Mexico are among the nations that have tried to reassure citizens about the vaccine’s benefits and have announced that they will continue their respective vaccination campaigns.

“An analysis of our safety data of more than 10 million records has shown no evidence of an increased risk of pulmonary embolism or deep vein thrombosis in any particular age group, gender, batch or country with AstraZeneca COVID-19 vaccine.” said an AstraZeneca spokesman.

“In fact, the number of these types of events observed is significantly lower in vaccinated people than would be expected in the general population.”

What do the experts say?

The EMA’s safety committee is investigating the problem, but has determined that there is currently no evidence that the vaccination caused blood clots. It should be noted that these are not listed as side effects of this vaccine.

The European Medicines Agency also noted that the data available so far showed that the number of blood clots in vaccinated people is no higher than in the general population.

“Reports of previously received blood clots are no greater than the numbers that would have occurred naturally in the vaccinated population,” said Dr. Phil Bryan, Vaccine Safety Director for the UK Medicines and Health Products Agency.

“Public safety will always come first. We will continue to examine this issue carefully, but the evidence available does not confirm the vaccine is the cause. People should still get their COVID-19 vaccine when prompted become.” Said Bryan.

Peter Brownsea, a Southampton resident, receives the Oxford / AstraZeneca Covid-19 vaccine from a member of the Hampshire Fire and Rescue Service at a temporary vaccination center at the Basingstoke Fire Station in Hampshire, southern England, while crews continue to answer 999 emergency calls.

Andrew Matthews | AFP | Getty Images

Stephen Evans, Professor of Pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said: “The problem with spontaneous reports of suspected vaccine side effects is the tremendous difficulty in distinguishing a causal effect from a coincidence.”

“This is especially true when we know that Covid-19 disease is very closely related to blood clotting and that there have been hundreds, if not many thousands of deaths caused by blood clotting as a result of Covid-19 disease. That first thing to do is to be absolutely sure that the clots were not caused by any other cause, including Covid-19, “added Evans.

How does the vaccine work?

The Oxford AstraZeneca vaccine is designed to prevent coronavirus in people aged 18 and over. It’s made up of an adenovirus that has been modified to contain the gene to make a protein from SARS-CoV-2, the virus that causes Covid-19.

The most common side effects of the shot, which does not contain the virus and cannot cause Covid, are typically mild or moderate and improve within a few days after vaccination.

In late clinical studies, the AstraZeneca-Oxford shot was found to have an average of 70% effectiveness in protecting against the virus.

A recent study by Oxford researchers found that the Covid vaccine was 76% effective at preventing symptomatic infection for three months after a single dose and that the effectiveness rate actually increased with a longer interval between the first and second dose.

– CNBC’s Holly Ellyatt contributed to this report.