The association of pleural effusion and pulmonary embolism

Editor – We would like to share ideas on the publication ‘Arterial and venous thrombotic stroke after ChAdOx1 nCoV-19 vaccine’.¹ Wills et al concluded that ‘These cases illustrate that physicians should be especially mindful of vaccine-induced thrombosis with thrombocytopenia (VITT) in the context of evolving evidence on treatment and in view of the potentially rapid and catastrophic neurological deterioration, leading to fatality despite best supportive care.’ We concur that there might be adverse effects of the COVID-19 vaccine and that neurological complication might be a serious one. In the reported cases, stroke occurred but the neurological disorder might or might not be associated with the vaccine. There are many possible aetiologies of a thrombotic event after vaccination.² Vaccines might induce abnormal immunity or high blood viscosity and result in thrombotic event.² There is also a chance of coincidence due to a background medical problem or concurrent medial disorder.^2,3 It is necessary to rule out the other possible causes for final conclusion on the vaccine-induced thrombotic event.