‘Whether the blood issues are ultimately linked to only one vaccine, or two vaccines, or more, it’s absolutely crucial to remember the unrelenting death toll from the coronavirus itself—and the fact that COVID-19 can set off its own chaos in the circulatory system, with blood clots showing up in “almost every organ.” That effect of the disease is just one of many reasons the European Medicines Agency has emphasized that the “overall benefits of the [AstraZeneca] vaccine in preventing COVID-19 outweigh the risks of side effects.” The same is true of Johnson & Johnson’s. These vaccines are saving countless lives across multiple continents.
‘But it’s also crucial to determine the biological cause of any vaccine-related blood conditions. This global immunization project presents a lot of firsts: the first authorized use of mRNA vaccines like the ones from Pfizer and Moderna; the first worldwide use of adenovirus vectors for vaccines like AstraZeneca’s, Johnson & Johnson’s, and Sputnik V; and the first attempt to immunize against a coronavirus. Which, if any, of these new frontiers might be linked to serious side effects? Which, if any, of the other vaccines could be drawn into this story, too? How can a tiny but disturbing risk be mitigated as we fight our way out of this pandemic? And what might be the implications for vaccine design in the years to come?
‘To answer these questions, scientists will have to figure out the biology behind this rare blood condition: what exactly causes it; when and why it happens. This is not an easy task. While the evidence available so far is fairly limited, some useful theories have emerged...
- Theory 1: Platelet problems
- Theory 2: The spike’s the problem
- Theory 3: A suspect sequence
- Theory 4: The mixed bag
Read here (The Atlantic, Apr 17, 2021)
