Vaccines may be revamped to avoid blood clots, German scientists claim | COVID-19 | Coronavirus

Summary

A study from German scientists may have discovered why some people experienced rare blood clots after receiving AstraZeneca and Johnson & Johnson COVID-19 vaccines. These vaccines use adenoviruses, which can enter the cell's nucleus, leading to the spike protein fragmenting and causing blood clots in rare cases. Scientists propose a simple fix: modifying the adenovirus to prevent the spike protein from breaking apart. Johnson & Johnson is already investigating this. Although the findings are not yet peer-reviewed, the vaccines are still recommended, as their benefits outweigh the risks.

Takeaways

• 🩸 Reports of blood clots among people who received the AstraZeneca and Johnson & Johnson vaccines almost derailed the vaccination drive.
• 🌍 Many countries stopped using these vaccines, and some still don’t use them.
• 🔬 Experts recommended the vaccines, despite not fully understanding the cause of the blood clots.
• 🧬 German scientists have found a potential cause for these clots and may have a solution.
• 🦠 The vaccines in question are adenovirus-based, which are typically harmless and commonly used for colds.
• 💉 Adenoviruses are used to deliver the genetic message to cells to create spike proteins from the virus, triggering an immune response.
• ⚠️ The problem arises when adenoviruses enter the cell’s nucleus, causing the spike protein to break up, which may lead to blood clots.
• 💻 This issue doesn’t occur with mRNA vaccines, as they deliver the vector to cellular fluid, not the nucleus.
• 🛠 The proposed solution is to modify the genetic message to prevent the spike protein from splitting apart.
• 📊 Although the theory sounds promising, it still requires peer review before conclusions can be fully drawn.

Q & A

What was the main concern about the AstraZeneca and Johnson & Johnson vaccines?

The main concern was the occurrence of blood clots among people who received these adenovirus-based vaccines.

Why did some countries stop using AstraZeneca and Johnson & Johnson vaccines?

Many countries paused the use of these vaccines due to concerns about rare but serious blood clotting events, and some have still not resumed their use.

What technology do AstraZeneca and Johnson & Johnson vaccines use?

Both vaccines use adenoviruses, which are modified to disable their ability to cause illness while still being able to enter human cells to deliver a message for the immune system.

What makes adenoviruses useful in these vaccines?

Adenoviruses can carry genetic information into cells without causing disease, making them an ideal vector for delivering the genetic code to produce spike proteins that stimulate an immune response.

How do adenovirus-based vaccines cause blood clots, according to the study?

The study suggests that the adenoviruses in these vaccines enter the cell's nucleus, where the spike protein breaks up. Some of these broken parts might lead to blood clots in rare cases.

How do mRNA vaccines differ from adenovirus-based vaccines in terms of blood clot risk?

mRNA vaccines deliver the vector to the cellular fluid, not the nucleus, reducing the risk of the spike protein breaking up and causing blood clots.

What potential solution did German scientists propose to prevent blood clots in adenovirus-based vaccines?

The scientists suggest altering the genetic message inside the adenovirus envelope to prevent the spike protein from splitting apart, which could reduce the risk of blood clots.

How has Johnson & Johnson responded to the findings of the German scientists?

Johnson & Johnson has expressed support for continued research and analysis of the rare blood clot events and is working with global health authorities to address the issue.

What is the current stance of health authorities like the WHO and the European Medicines Agency on these vaccines?

Both the WHO and the European Medicines Agency continue to back the use of the AstraZeneca and Johnson & Johnson vaccines, despite the concerns about blood clots.

What should people keep in mind about these vaccines while awaiting further studies?

While the study is not yet peer-reviewed, the vaccines are still considered effective and the benefits of vaccination outweigh the risks posed by the blood clots, which are rare.