Modern Vaccine Side Effects: Stroke Risk?

There is no evidence that the Moderna vaccine can cause strokes. In fact, a study from the Universities of Cambridge, Bristol, and Edinburgh found that COVID-19 vaccinations may help protect against potentially deadly blood clots and reduce the risk of heart attacks and strokes. The more widely used Pfizer and Moderna vaccines have not been linked to an increased risk of blood clots. However, it is important to note that rare cardiovascular complications from COVID-19 vaccines are still possible, but these risks are very rare compared to the benefits of the vaccines.

No evidence Moderna vaccine causes strokes

There is no evidence that the Moderna vaccine causes strokes. In fact, according to a study by the Universities of Cambridge, Bristol and Edinburgh, COVID-19 vaccinations may help to reduce the risk of heart attacks and strokes. The study, which analysed health data from nearly 46 million adults in England, found that the incidence of arterial thromboses (blood clots that block blood flow to the heart or brain) was lower in the weeks following a first dose of a COVID-19 vaccine.

The Health Sciences Authority (HSA) in Singapore has also stated that there has been no uptick in heart attacks or strokes among vaccinated people, and no evidence that the COVID-19 vaccines used there, including Moderna, can directly cause these events. This is supported by the findings of Professor Teo Yik Ying, dean of the National University of Singapore's Saw Swee Hock School of Public Health, who noted that there have been no established links between cases of stroke or heart attack and the Moderna vaccine.

While rare cases of blood clots have been reported with other COVID-19 vaccines, such as AstraZeneca and Johnson & Johnson, the Moderna vaccine has not been linked to an increased risk of blood clots. The British Heart Foundation Data Science Center has confirmed that the Moderna vaccine is safe and effective, and it is recommended for those with a history of certain types of blood clots, such as cerebral venous sinus thrombosis (CVST) or antiphospholipid syndrome with thrombosis.

It is important to note that strokes can occur for a variety of reasons and can affect anyone at any age. While there may be concerns about the potential side effects of vaccines, it is crucial to weigh the risks and benefits. Vaccination remains key to protecting against serious outcomes of COVID-19 infection, and the benefits of vaccination far outweigh the very rare risks.

COVID-19 vaccines don't increase stroke risk

There is no evidence that COVID-19 vaccines, including the Moderna vaccine, directly cause strokes. While there have been rare cases of individuals experiencing strokes after receiving the vaccine, these incidents are not above the baseline rate of strokes in the general population.

The Health Sciences Authority (HSA) in Singapore, for instance, reported no uptick in heart attacks or strokes among vaccinated individuals and stated that there is no evidence that the COVID-19 vaccines used in the country, including the Moderna vaccine, can directly cause these events. Similarly, the Mississippi State Department of Health noted that strokes are not associated with the Johnson & Johnson vaccine, despite a reported case of an individual experiencing a stroke shortly after vaccination.

It is important to note that the occurrence of strokes or heart attacks in vaccinated individuals may be coincidental and not directly related to the vaccination. The large number of people being vaccinated means that some individuals may experience these medical events by chance in the days or weeks after vaccination.

Furthermore, the COVID-19 virus itself is associated with a higher risk of ischemic strokes, as demonstrated by a study published in the Journal of the American Heart Association. This further emphasizes that the vaccines do not increase the risk of strokes.

While there have been concerns and reports of rare side effects associated with some COVID-19 vaccines, the benefits of vaccination continue to outweigh the potential risks. Vaccination remains a key tool in the battle against COVID-19 and provides better protection against serious outcomes of infection.

Vaccines may reduce heart attack and stroke risk

There is no evidence that the Moderna vaccine can cause strokes. The Health Sciences Authority (HSA) stated that there has been no uptick in heart attacks or strokes among vaccinated people and that there is no evidence that the vaccines can directly cause these events.

In fact, vaccines may reduce the risk of heart attacks and strokes. COVID-19, on the other hand, has been linked to an increased risk of cardiovascular events, including heart attacks and strokes, for up to three years after infection. This risk is even higher for those who were hospitalized with severe COVID-19.

One study found that people who were infected with COVID-19 in 2020, before vaccines were available, had twice the risk of a heart attack or stroke compared to those who didn't have COVID-19. This risk was nearly four times higher for those with severe cases of COVID-19 that required hospitalization.

Another study, which followed UK-based adults for three years after their initial COVID-19 test, found that COVID-19 survivors were 60% more likely to suffer a heart attack within a year of beating the virus, even if their infection was mild. This risk persisted over the three years of the study.

The exact mechanisms behind the link between COVID-19 and increased cardiovascular risk are not yet fully understood, but several factors have been proposed. One factor may be the inflammation that occurs throughout the body during a COVID-19 infection, which can put pressure on blood vessels and increase the risk of blood clots. Blood clots can lead to heart attacks and strokes by blocking normal blood flow.

In rare cases, COVID-19 can also cause myocarditis, or inflammation of the heart muscle, which can be life-threatening and damage the heart. Additionally, COVID-19 has been found to affect the electrical impulses that control the heart, leading to an irregular heartbeat and potentially causing heart failure and stroke.

While the focus has been on the potential cardiovascular risks of COVID-19 vaccines, the evidence suggests that it is the virus itself that poses a significant risk to heart health.

Moderna vaccine is an mRNA vaccine

There is no evidence that the Moderna vaccine can directly cause strokes. In fact, the Health Sciences Authority (HSA) has stated that there has been no uptick in heart attacks or strokes among vaccinated people, and no evidence that the Covid-19 vaccines used in Singapore, which include the Moderna vaccine, can directly cause them. This was HSA's first update on the safety of the mRNA vaccines used in the country.

The Moderna vaccine is an mRNA vaccine, which stands for messenger RNA. This technology is proving effective in fighting melanoma, according to Moderna. The same mRNA technology that fuelled its COVID-19 vaccine is now being used to develop a cancer vaccine. The company has presented promising results from a trial involving 157 people with advanced skin cancer.

The Moderna vaccine is not the only mRNA vaccine available. For instance, Moderna and Pfizer both have vaccines to protect seniors in Canada against severe illness caused by the respiratory syncytial virus (RSV). The Moderna vaccine is the first RSV shot to come in a pre-filled syringe, which saves time for healthcare workers and reduces the risk of errors in administering it.

While there is no evidence that the Moderna vaccine can cause strokes, it is important to note that some people have experienced adverse reactions to the vaccine. For example, VAERS, the CDC's Vaccine Adverse Event Reporting System, reported that 10 people had ischemic strokes after receiving the Moderna vaccine. However, it is important to note that these incidents are "below baseline" or what is expected to naturally occur in the US population, according to Martha Sharan of the CDC's public affairs division.

Blood clots are a rare side effect of vaccines

There is no evidence that COVID-19 vaccines, including the Moderna vaccine, directly cause strokes or heart attacks. However, rare cases of blood clots have been reported with certain vaccines, such as the AstraZeneca and Johnson & Johnson vaccines. In extremely rare cases, the Johnson & Johnson vaccine has been linked to a rare blood clotting disorder called cerebral venous sinus thrombosis. This occurred in approximately four cases per 1 million doses.

The British Heart Foundation Data Science Center reported that the incidence of arterial thromboses, such as heart attacks and strokes, was up to 10% lower in the 13 to 24 weeks after the first dose of a COVID-19 vaccine. This is based on data from nearly 46 million adults in England. The risk of these events was further reduced after the second dose, with up to a 27% lower incidence after the AstraZeneca vaccine and up to a 20% lower incidence after the Pfizer/BioNTech vaccine.

The more widely used mRNA vaccines, such as Pfizer and Moderna, have not been linked to an increased risk of blood clots. In fact, studies suggest that COVID-19 vaccines may help protect against potentially deadly blood clots. However, it is important to note that rare cardiovascular complications from COVID-19 vaccines are still possible, but the benefits for vaccinated people far outweigh the very rare risks.

While there have been reports of athletes experiencing strokes or blood clots, there is no evidence linking these conditions to the COVID-19 vaccines. In some cases, the health issues were caused by other underlying medical conditions or genetic variations. It is important to note that blood clots can occur in anyone, regardless of age, and there are many risk factors beyond vaccinations.

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