[Science Mag reporter] Kupferschmidt
passed on more information from Germany’s Paul-Ehrlich Institute just this morning. 2.7 million people have received the AZ/Oxford vaccine there, and 31 patients have been identified with cerebral venous thrombosis. Not all of those are HIT or VIPIT, though, because only 19 of the 31 had thrombocytopenia. There have been nine deaths, and as always, key questions are how many cases one would expect in the population that’s been dosed so far. Earlier this month, the figures were 1.7 million vaccinated and 7 cases of CVT, and the institute said that they would have expected about one case as normal background. The EMA, when they came out recommending the vaccine earlier this month,
noted that figuring these background rates is not easy. But they found that if there is indeed an imbalance, it’s most noticeable in the younger age cohort and not in the older. The PEI mentioned today that of the 31 cases they have analyzed, 29 of them have been women, which certainly seems significant as well.
The UK experience with this vaccine has apparently shown no overall increase in thrombotic events – if anything, the vaccinated cohort has been slightly
lower in that regard than the general population. But if there is an increased risk in people under 50, especially women, that’s actionable, as they say, even if the risk is very small (as it certainly appears to be).