It seems I was too dogmatic in my condemnation of all reservations about the Oxford/AstraZeneca Covid-19 vaccine a month ago. It remains the case that any adverse side-effects of the vaccine are minuscule compared with the dangers of catching SARS/CoV-2, dangers which include affecting the brain, but a scientist has postulated a mechanism by which the vaccine may stimulate an auto-immune response resulting in abnormal platelet production in a small segment of the younger population. As a result, Oxford University has suspended a trial involving children and teenagers.
As I understand it, the proposed mechanism applies to all vectored vaccines. The university has hitherto produced candidate vaccines against 'flu, Zika and MERS. Moreover, Johnson & Johnson's new vaccine, developed by their Belgian subsidiary is of this type.This is still awaiting approval in the US. More data about very rare events are clearly required.
It does, however, seem suspicious that only AstraZeneca (AZ) has attracted adverse publicity about their vaccine. The platelets scare is the latest of several reports of different national health bodies suspending or attenuating programmes of vaccination involving AZ. Some liberals have pointed out that, alone among the big pharmaceutical companies, AZ is selling the vaccine at cost and is "collaborating with a number of countries and multilateral organisations to make the University of Oxford’s vaccine widely accessible around the world in an equitable manner". At present, demand is outstripping supply, but the time may not be far distant when vaccination against pandemic diseases becomes a "buyer's market" and competition among the multinational giants becomes fierce and profits are squeezed. An ethical approach to pricing will not be welcomed by rivals.