Johnson & Johnson vaccine and AZ vaccine (AstraZeneca vaccine) have successive cases of blood clots; what are the symptoms to be alerted?
Recently, there have been a series of blood clots in the Johnson & Johnson vaccine and AZ vaccine (AstraZeneca vaccine), causing public concern. What are the causes of blood clots and even fatalities after vaccination? What are the symptoms to be alerted?
What is a blood clot?
A blood clot occurs when there is a clot in the blood that blocks a blood vessel and stops the circulation of blood.
Typically, a blood clot causes a stroke if it occurs in the brain, a myocardial infarction if it occurs in the heart, or a venous thrombosis in the legs if it occurs in the lower extremities.
However, the blood clots that occurred with the Johnson & Johnson and AZ vaccines are not the same as common blood clots. And, there are striking similarities between the two. Let’s analyze them one by one.
The main initial symptom in the 6 patients with blood clots from Johnson & Johnson vaccine was headache
On April 13, the FDA and CDC announced a recommendation to suspend Johnson & Johnson vaccines and to investigate the causal relationship between Johnson & Johnson vaccines and blood clots.
Six of the people who received the Johnson & Johnson vaccine developed severe thrombotic symptoms of cerebral venous sinus thrombosis (CVST) with thrombocytopenia. All six were female and ranged in age from 18 to 48 years. Symptoms occurred 6 to 13 days after vaccination. One of the women died and the other two were in intensive care.
Six of the people who received the Johnson & Johnson vaccine had severe thrombotic symptoms of cerebral venous sinus thrombosis (CVST) accompanied by thrombocytopenia.
Dr. Tom Shimabukuro, head of vaccine safety for the CDC’s Covid-19 response team, noted that all six individuals had one major symptom – headaches.
There is also a seventh “probable case. A patient who died from a blood clot was also reported in Johnson & Johnson’s clinical trial.
What are the details of the AZ vaccine blood clot side effects?
Just a week ago, the European Medicines Agency (EMA) announced that it had established a link between the AZ vaccine and blood clots, and included “unusual blood clots with reduced platelets” as a rare side effect of the AZ vaccine.
On April 9, the New England Journal of Medicine (NEMJ) published two simultaneous medical studies from Germany and Norway, reporting rare, abnormal blood clots in 11 and 5 patients, respectively, after receiving the first dose of AZ vaccine.
More details can be seen from these two studies for the AZ vaccine. These cases have distinct characteristics.
The New England Medical Journal (NEMJ) published two studies reporting rare, abnormal blood clots in 16 patients after receiving the AZ vaccine.
● Significantly more common in women
●Median age was below 40 years
●Occurred 1 to 2 weeks after the first injection, with a significant temporal correlation with vaccination
●Most patients presented with headache symptoms.
● Nine deaths were reported in 16 reported cases.
They found 2 other significant features of AZ vaccine-associated thrombosis.
AZ vaccine-associated thrombosis, and 2 other distinguishing features.
The thrombosis occurred mostly in the cerebral veins and the patients showed a rapid and severe drop in platelets.
Platelets are an important component when we do routine blood tests. It is small, but its function is not small at all. The platelet value in a normal person is 100,000 to 300,000 per microliter (mm3). But the platelets in these patients, on average, fall to less than 1/3 of the lower limit of normal value, which is quite low and is a very dangerous sign in clinical practice. And the lower it drops, the greater the likelihood of a life-threatening condition.
We have seen that in patients who developed thrombosis after the Johnson & Johnson and AZ vaccines, their conditions have an extremely similar pattern.
What are the causes of vaccine-induced blood clots?
So, why did the side effects of blood clots and decreased platelets occur after the AZ vaccination? Because the cases occurred so recently, there is no clear answer. But two research teams found that these patients developed autoimmunity – their bodies developed antibodies to their own platelets and their related components. The antibodies wrapped up the platelets and were processed by immune cells, resulting in a depleting decline in platelets, accompanied by abnormal blood clots.
Researchers have termed this phenomenon “vaccine-induced immune thrombotic thrombocytopenia” (VITT).
So, why does the AZ vaccine cause autoimmunity to platelets in the body? The deeper reasons are not yet answered, but I speculate that there are two possibilities.
Why does the AZ vaccine cause the body to develop autoimmunity to platelets? There are two possibilities for speculation.
- Adenovirus vector problem
The AZ vaccine is an adenoviral vector vaccine, using a modified chimpanzee adenovirus as the vector. It was previously known to the medical community that adenovirus binding to platelets can cause platelet activation, which in turn may lead to platelet depletion.
The Johnson & Johnson vaccine is also an adenovirus vector vaccine, and when the thrombotic side effects of the AZ vaccine surfaced, immediately after the FDA and CDC called off the Johnson & Johnson vaccine, this indicates that the medical community has concerns about adenovirus vector vaccines. This possibility, for now, cannot be ruled out.
- The problem of New Crown (CCP virus) itself
On the other hand, the new crown (CCP virus) virus has only been around for a year or so, and because the epidemic has been so severe, a lot of effort has been spent on developing a vaccine, and knowledge of the pathological mechanisms of the virus itself is still superficial. Vaccines mimic viruses, and the unexpected side effects of vaccines suggest that certain pathological mechanisms of the new coronavirus (CCA virus) in humans may not be fully understood.
For example, it is widely believed that neo-coronavirus (CCLV) viruses enter cells and only need to pass through the ACE2 receptor. However, a study published in November 2020 in the top medical journal Cell proposed that viral invasion of cells, also requires a co-receptor, acetyl heparan sulfate. Acetyl heparan sulfate is a molecule that is widely found on the surface of cells. That said, ACE2 is only part of the story, not the whole story.
This incident reminds us that we may need to calm down and think carefully about issues related to vaccine safety and reflect on the pros and cons of vaccine development.
How high is the rate of thrombosis with Johnson & Johnson and AZ vaccines?
So what is the rate of rare blood clots from vaccines? As of April 4, about 10 blood clots (mainly cerebral venous sinus thrombosis) occurred per 1 million in people who received the AZ vaccine in European countries such as the United Kingdom.
In the general population, the incidence of cerebral venous sinus thrombosis was 3 to 4 cases per 1 million people according to a 2009 study; 15 cases per 1 million people according to a 2018 US study. However, cerebral venous thrombosis is not easily diagnosed, and the true incidence is unclear.
In contrast, about 7 million people in the United States currently administer the Johnson & Johnson vaccine, of which 6 cases of thrombosis occur, a rate of nearly 1 per 1 million people.
The incidence is one aspect, but on the other hand, the location, severity and consequences of the clots should be considered.
In particular, these thromboses did not occur in the elderly, but in the young population, at sites in the deep veins of the brain, causing several deaths. As of March 22, European regulators had reviewed 86 cases in detail, 18 of which were fatal, with mortality rates as high as 20 percent.
This thrombotic side effect of the vaccine, although rare, caused adverse reactions with fatal injuries in a young and healthy population, and the risks clearly outweighed the benefits. Therefore, it is reasonable for many countries to suspend AZ vaccination for people under 60 years of age.
Be alert to 2 major symptoms after vaccination
So, how can you identify possible rare blood clot symptoms after a Johnson & Johnson, AZ vaccine injection? European regulators and the CDC in the United States each warn to seek medical attention quickly if any of the following occur within three weeks of receiving the vaccine.
Severe and persistent headache, persistent abdominal pain, swelling or pain in the legs, blurred vision, shortness of breath, and petechial hemorrhagic spots on the skin outside the injection area.
How to recognize possible rare blood clot symptoms after Johnson & Johnson, AZ vaccination?
Two of these conditions are distinctive features.
1) Headache: Especially persistent and severe headache should not be ignored, it is by far the most dominant symptom feature in all cases. In case of venous thrombosis of the brain, it may also be accompanied by nausea, vomiting, and blurred vision.
2) Petechial spots on the skin: Pay attention to monitoring for a possible rapid and heavy drop in platelet count, when petechial spots on the skin appear, there may be a problem with platelets. If you suspect symptoms of declining platelets after vaccination, you may wish to visit the hospital for a simple routine blood test to rule out the risk. Also, baseline platelet values prior to vaccination can be valuable in providing a judgment.
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