COVID-19: Risk of blood clot 8 times higher after infection than after AstraZeneca vaccine

The risk of developing blood clots after having COVID-19 is eight times higher than after being given AstraZeneca-Oxford’s coronavirus vaccine, concluded a study by Oxford University. As per the research, cerebral venous thrombosis (CVT) occurred in 39 million patients of COVID-19 as compared to nearly five million people who have been administered with AstraZeneca jabs. The study determined the results after monitoring over 500,000 coronavirus patients and the risk was reported to be at least 100 times higher than normal after infection. 

Amid fears of blood clots in some of the people who received AstraZeneca’s COVID-19 vaccine, several nations have limited the use of shots to a certain age or temporarily halted its rollout with Denmark dropping the jab permanently from its national immunisation campaign. UK’s medical regulator had previously declared the AstraZeneca-Oxford’s vaccine safe and limited its use to people below the age of 30. Now Oxford study has suggested that around a third or 30% of CVT reports after COVID-19 infection were common in people under 30.

Comparing the two, the study stated that the cases for CVT among COVID-19 positive people stands at 39 cases per one million people. Meanwhile, for a million who received AstraZeneca jab, there will be five cases of CVT over a period of two-week. However, the scientists also warned that all comparisons must be interpreted carefully since data is still being put together from various sources. The researchers also noted that they were not able to determine the relative risk of developing blood clots after AstraZeneca jabs since the baseline rate of the condition still remains uncertain. 

Rare Reaction Of Antibodies Due To AstraZeneca

As reports of blood clots after receiving AstraZeneca’s COVID-19 vaccine has fueled vaccine hesitancy, scientists from Germany and Norway have found that people who developed the clots after administering the jabs had produced antibodies that activated their platelets, a blood component involved in clotting. As per New York Times, the fresh reports have added extensive details about what the researchers have already stated publicly about the blood disordered being flagged in some European nations.

Even though the reason behind the occurring of the rare reaction is still not known, reportedly younger people appeared to be more susceptible than the older ones. However, the researchers have said that no preexisting health conditions are known yet to predispose people to the problem of clots and admitted that there is no way to determine which individuals are at greater risk.

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