Most Reported Cases Of Blood Clots Have Been In Women Under The Age Of 60 Within Three Weeks Of Vaccination
Six people have experienced blood clotting after receiving Johnson & Johnson’s one-dose vaccine in the U.S., The New York Times reported. All six were women between the ages of 18 and 48, who developed blood clotting within one to three weeks after vaccination. Blood clotting has also been reported as a rare reaction following the AstraZeneca COVID vaccine, which is not yet available in the U.S. According to the European Medicines Agency , most of these cases have occurred in women under the age of 60 within two weeks of vaccination. Christian Bogdan, a member of Germany’s vaccine committee, told Reuters that the risk of blood clotting was highest in women between the ages of 20 and 59, observed between four to 16 days after receiving the AztraZeneca vaccine. And for more concerning reactions, If 1 of These 3 Body Parts Starts Swelling Up After Your Vaccine, Call a Doctor.
Can You Explain The Current Concerns About Blood Clotting Risk Associated With Vaccines
Mounting evidence links the Astra Zeneca vaccine to an increased risk of a rare but often fatal blood clotting condition in the brain called sagittal sinus vein thrombosis. Most of the cases reported so far have been in women younger than 60 and have occurred within one to two weeks after the first vaccine dose. The absolute risk appears to be extremely low, on the order of one chance in at least several hundred thousand, so on balance there should be a net benefit of getting the vaccine, especially in older people who have the greatest need for protection from COVID-19. But Germany, for example, has suspended the use of the Astra Zeneca vaccine in people younger than 60, and other countries have made similar rulings or recommendations. While the AstraZeneca vaccine is not yet approved for use in the United States, on April 13, the CDC and FDA recommended a pause in administration of the Johnson & Johnson COVID-19 vaccine because of six reported cases of this type of clotting from among 6.8 million doses administered in the country.
In the case of venous blood clots in the brain associated with the AstraZeneca vaccine, a special type of antibody known as anti-PF4 antibody, linked to cases of blood clotting plus low platelet counts in the setting of heparin use, appears to be involved. It is suspected that a similar type of antibody may be causative in the six clotting cases linked to the J& J vaccine.
What This Means For The Future
Study co-lead, Dr. Abhishek Singharoy, assistant professor in the School of Molecular Sciences at Arizona State University, said, Its really critical to fully investigate the vector-host interactions of the vaccine at a mechanistic levelhis will assist in understanding both how the vaccine generates immunity, and how it may lead to any rare adverse events, such as VITT.
However, some important questions remain:
- Why does TTS occur in such a small number of vaccinated people?
- Do these findings mean that scientists can reengineer the vaccine to prevent TTS?
- Can scientists reduce the negative charge of the vaccine particle?
- Clinically, can we predict which people are at higher risk from TTS, and can we develop alternative modified vaccines to prevent clots for these high risk individuals?
Despite these questions, Dr. Raghav Palankar, a researcher at the Institute of Immunology and Transfusion Medicine in Germany, has called the research Quite a game-changing fundamental discovery with significant translational implications.
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What Do We Know About Blood Clots And Covid
Paul Offit, MD: Hi, my name is Paul Offit. I’m talking to you today from the Vaccine Education Center at the Children’s Hospital of Philadelphia. It’s Wednesday, May 12th, 2021. So probably a question that’s come up recently is, what’s the story with blood clots and these COVID-19 vaccines? Well, first of all, the two messenger RNA vaccines, those made by Pfizer and Moderna, don’t increase the risk of blood clots, so that’s good. But the more recent vaccine, the so-called Johnson & Johnson vaccine, which is a replication defective adenovirus vector vaccine, does appear to be a rare cause of blood clots, including serious blood clots. And by serious blood clots, I mean a blood clot of the brain that has the name cerebral venous sinus thrombosis, or CVST. It’s rare. It occurs in about 1.9 per million people who get this. It’s more common in younger people, especially more common in younger women. So that is truly a real, but rare side effect. Now, you should also note that the virus SARS-CoV-2 also causes blood clots. It also causes the brain blood clots, the so-called CVST, at a rate of 5 to 6 per million. So, you’re actually more likely to have that particular blood clot if you get infected with the virus than if you get the vaccine. But again, it is understandable how a young, especially a young woman, could reasonably say that I really would prefer the mRNA vaccines because they don’t have this rare side effect.
Thank you.
The Timeframe Of Risk Is Narrow 4

Third: If you did receive the Johnson & Johnson/Janssen vaccine, the presumed window of risk is quite narrow between 4 and 28 days after vaccination. VITT has not been reported to occur immediately or longer-term after vaccination.
Demographic and clinical risk factors for the development of VITT are uncertain. Most patients who developed VITT were younger than 60 years old. While all of the cases following the Johnson and Johnson/Janssen vaccine in the United States occurred in women, both men and women have been diagnosed with VITT following the AstraZeneca vaccine in other parts of the world. There is no evidence that patients with a history of thrombosis, thrombophilia, or HIT are at increased risk for VITT.
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What Is The Current Standard Practice For Preventing Such Clots In Covid
One practice for which there is now a wide consensus is to give a prophylactic, or preventive, dose of an anticoagulant, usually low molecular weight heparin, to anyone who is hospitalized with COVID-19assuming they dont have a condition requiring a different treatment. The American Society of Hematology has suggested that, while noting that more evidence is needed.
In fact, although the issue is not yet settled, there is evidence from three international trials that for hospitalized patients who are moderately ill with COVID-19 but do not yet require intensive care, full doses of anticoagulants are even better than prophylactic doses in preventing disease progression and death.
At the same time, there is now good evidence from studies that COVID-19 patients whose illness progresses enough that they are admitted to intensive care, but dont have an identified or suspected clot, should be kept on prophylactic doses of anticoagulants, not full doses. In other words, at that advanced stage of disease, a full dose appears to be futile in terms of preventing clots more effectively. Of course, someone admitted to the ICU with a known blood clot in the lung, or a known deep-vein thrombosis, would receive full-dose anticoagulant treatment.
Take Blood Clots Seriously
Blood clots can occur in the brain. They can also form in a deep vein and, if left unchecked, travel from a deep vein to a lung . Venous thromboembolism frequently recurs within 10 years, according to the CDC.
The condition can be manageable and treatable, experts say. But it’s underdiagnosedand can also be a dangerous medical emergency, tied to strokes, heart attacks, disability and death: Up to 100,000 people die from blood clots annually.
Smoking, undergoing hospitalization or surgery, being overweight, immobile or sitting for long periods of time, having cancer and experiencing physical traumaespecially a vein injurycan all make you more vulnerable to a blood clot.
“It’s a very wide spectrumit really depends on where the clot is and what’s going on medically with the individual,” Dr. Schimmoeller says.
“Being up and active keeps circulation moving”
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Symptoms To Watch For
Between 4 and 28 days after your J& J/Janssen vaccine, watch for symptoms of a clot including severe headache, vision changes, severe abdominal pain, or nausea and vomiting.
Your physician may recommend imaging appropriate to your symptoms along with complete blood count laboratory tests. If either test is normal , then VITT can be excluded. If BOTH tests are abnormal , hospitalization for further evaluation and treatment guided by a hematologist or other thrombosis expert is appropriate.
How Is Tts And Blood Clots Linked To The Astrazeneca Vaccine
Thrombosis with thrombocytopenia syndrome is a very rare side effect of the AstraZeneca COVID-19 vaccine.
In Australia, symptoms of TTS have occurred between 4 and 42 days after vaccination with the AstraZeneca vaccine. The risk of TTS appears to be higher in people aged under 60 years of age.
The blood clots can occur in different parts of the body, such as the brain or in the abdomen .
The mechanism that causes TTS is not fully understood, but it is similar to heparin-induced thrombocytopenia , a rare reaction to a medication called heparin.
TTS is different from general clotting conditions such as deep vein thrombosis or pulmonary embolism .
Researchers are still working to understand TTS. One theory is that, in rare cases in some people, the AstraZeneca vaccine might produce antibodies that react with platelets making them stick together.
This can cause blood clots, which stops platelets from circulating through the body.
Its important to note that only a link has been established. The AstraZeneca vaccine has not been proven to cause TTS. Blood clots are common and not all types of blood clot that occur after vaccination will be linked to the vaccine.
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Can I Have My Second Dose Of The Astrazeneca Vaccine
If it does occur, TTS is more likely to appear after the first dose of the AstraZeneca vaccine. People who have already had their first dose of the AstraZeneca vaccine without any serious side effects can safely and confidently get their second dose. This includes adults aged 18 to 59 years.
If you develop TTS after your first dose of the AstraZeneca vaccine, you’ll be offered a different type of vaccine for your second dose.
The AstraZeneca vaccine is considered to be safe. The benefits of vaccination against COVID-19 outweigh the risks associated with the AstraZeneca vaccine. This is especially true for older Australians who could become very unwell or die if they are infected with COVID-19.
COVID-19 itself poses 8 to 10 times the risk of blood clots than that of COVID-19 vaccines.
Sads: Sudden Adult Death Syndrome Or Covid Shots
The Signal That Cannot Be Silenced
In a June 13, 2022, Substack article, Dr. Pierre Kory also commented on this latest effort to explain away COVID jab deaths:
I recently posted a deeply referenced compilation of evidence detailing the historic humanitarian catastrophe that has slowly unfolded within most advanced health economies across the world. Caused by a global mass vaccination campaign led by the Pharma masters of BMGF/WHO/CDC that illogically targeted a rapidly mutating coronavirus.
They did it with what turned out to be the most toxic protein used therapeutically in the history of medicine.I cited studies and reports showing massive increases in cardiovascular deaths and neurologic disabilities amongst working age adults, beginning in 2021 only.
A disturbing signal screaming from the original clinical trials data, VAERS data, life insurance data, disability data, reports of cardiac arrests of professional athletes, rises in ambulance calls for cardiac arrests in pre-heart attack age young people, and the massive increases in illnesses and data manipulations in Department of Defense databases.
As these events become more and more recognized by the average citizen , a new pathetic Disinformation Campaign was launched in response trying to blame all the young people dying as simply a need for increased awareness of the rare condition called Sudden Adult Death Syndrome , rather than examples of the legions dying from the vaccines.
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What Is Blood Clotting
Blood clotting is a process your body uses to prevent bleeding. When a blood vessel is damagedfor example, if you cut yourselfblood cells called platelets rush to the site of the injury and clump together with proteins and other blood cells, forming a clot to plug the hole. This minimises further bleeding while your body starts repairing the damage.
However, sometimes a clot can form inside a vein or artery. This blocks the normal flow of blood in that part of the body and can cause serious harm, especially if it restricts blood flow to tissues or vital organs like the brain . There are lots of different reasons why problematic clotting might occursome common causes include recent surgery and reduced mobility, genetic disorders that make blood more prone to clotting, or medications that affect certain hormones, such as the oral contraceptive pill. Even sitting still for a long time, like on a long international flight, can lead to clotting in the deep veins of the legs.
Blood clotting is a complex process, involving many different proteins and chemical messengers all interacting with each other in a series of reactions. Venous thromboembolism, an umbrella term for several common blood clotting diseases, is quite common, affecting roughly 17,000 Australians each year. While cases can vary in severity, many are treatable with medications such as heparin and other anti-clotting treatments.
Do Vaccines Cause Other Bleeding Disorders

Other vaccines, particularly the one given to children for measles, mumps and rubella, have been linked to temporarily lowered levels of platelets, a blood component essential for clotting.
Lowered platelet levels have been reported in small numbers of patients receiving the Moderna, Pfizer-BioNTech and AstraZeneca vaccines. One recipient, a physician in Florida, died from a brain hemorrhage when his platelet levels could not be restored, and others have been hospitalized. U.S. health officials have said that the cases are being investigated, but they have not reported the findings of those reviews and have yet to indicate that there is any link to the vaccines.
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How Some Covid Vaccines Could Cause Rare Blood Clots
April 14, 2021 — A CDC advisory committee is debating the safety of the Johnson & Johnson COVID-19 vaccine today after the CDC and FDA recommended that states hold off on using it after six women developed a rare but serious blood clot after getting the single-dose vaccine.
The clot occurred in the vessels that drain blood from the brain and the six patients also had a a large drop in platelets, which increases the risk of bleeding.
This combination can lead to severe strokes that can lead to brain damage or death. Among the six cases, which came to light at the end of March and beginning of April, according to the CDC, one person died. They ranged in age from 18 to 48. More than 6.8 million doses of the Johnson & Johnson vaccine have been administered in the U.S.
According to a report to the Vaccine Adverse Event Reporting System , which is maintained by the Department of Health and Human Services, the woman who died was 45. She developed a gradually worsening headache about a week after receiving the Johnson & Johnson vaccine.
On March 17, the day she went to the hospital, she was dry heaving. Her headache had suddenly gotten much worse, and the left side of her body was weak, which are signs of a stroke. A CT scan revealed both bleeding in her brain and a clot in her cortical vein. She died on March 18.
This has experts questioning whether all vaccines of this type may cause these rare clots.
Astrazeneca Vaccine And Blood Clots: What Is Known So Far
In rare cases, an immune reaction has led to antibodies that caused a serious clotting disorder. But public health experts maintain the vaccines benefits far outweigh the risks for most people.
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The AstraZeneca-Oxford vaccine has been deployed against Covid-19 in at least 115 countries, some of them for several months now. But it wasnt until a few cases of a rare blood-clotting disorder some fatal emerged within the past month or so that many European nations began to rethink its use across all age groups.
Several of those countries, well stocked with alternate vaccines, have now limited use of the AstraZeneca-Oxford shot to older people, and a few have stopped using it altogether. While the incidence of these clotting disorders is extremely low, regulators and researchers are trying to raise public awareness of certain symptoms including headaches, leg swelling and abdominal pain especially in younger people who have been vaccinated.
Public health experts, however, have expressed concern that publicity surrounding the rare vaccine-related reactions will fuel hesitancy, a particular problem in Europe. They continue to emphasize that the AstraZeneca-Oxford vaccines benefits far outweigh the risks. In many nations, it is the only vaccine available.
Below are some frequently asked questions.
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Blood Clots Are Also A Complication Of Covid
Researchers have also seen a strong association between blood clots and COVID-19 infection itself, says Hyung Chun, MD, a Yale Medicine cardiologist. Unfortunately, in those who are sick enough with COVID-19 to be in the intensive care unit , blood clots have been a major factor in their illness, Dr. Chun says. Close to 20% of COVID-19 patients in the ICU develop blood clots, he says. Thats far higher than what youd expect for patients who are in the ICU for different conditions. Estimates Ive seen are in the 3 to 10% range for patients admitted for other reasons,” adds Dr. Chun.
COVID-19 infection seems to cause the blood vessels and the blood itself to behave in a way that promotes formation of blood clots, which is likely a key driver for poor outcomes, sometimes damaging vital organs and even leading to death, Dr. Chun says.
Dr. Chun and colleagues published a study in The Lancet Haematology after identifying a leading mechanism behind blood clots in COVID-19 patients. Yale Medicine hematologist Alfred Lee, MD, PhD, and George Goshua, MD, a hematology-oncology fellow, were also authors of the study. They found that endothelial cells play a surprising role in the formation of blood clots, especially as a COVID-19 patient becomes critically ill. They hope the finding will eventually contribute to determining treatment for the blood clots. So far, there is not a clear-cut answer, Dr. Chun says.