Medical Journal of Dr. D.Y. Patil Vidyapeeth

: 2022  |  Volume : 15  |  Issue : 4  |  Page : 613-

New COVID-19 vaccine, thiomerosol, and reversible cerebral vasoconstriction

Rujittika Mungmunpuntipantip1, Viroj Wiwanitkit2,  
1 Private Academic Consultant, Bangkok, Thailand
2 Department of Community Medicine, Dr. DY Patil University, Pune, Maharashtra, India

Correspondence Address:
Rujittika Mungmunpuntipantip
Private Academic Consultant, Bangkok

How to cite this article:
Mungmunpuntipantip R, Wiwanitkit V. New COVID-19 vaccine, thiomerosol, and reversible cerebral vasoconstriction.Med J DY Patil Vidyapeeth 2022;15:613-613

How to cite this URL:
Mungmunpuntipantip R, Wiwanitkit V. New COVID-19 vaccine, thiomerosol, and reversible cerebral vasoconstriction. Med J DY Patil Vidyapeeth [serial online] 2022 [cited 2022 Aug 11 ];15:613-613
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Full Text

Dear Editor,

COVID-19 vaccine is the hope for containment of COVID-19 pandemic. In preventive medicine, the vaccination is the best primary prevention of infectious disease. The new COVID-19 vaccine usually receives a registration certificate under emergency rules adopted during the COVID-19 pandemic, and there are limited data on efficacy and adverse effect of the new vaccine. Different COVID-19 vaccines might have different efficacies and adverse effects.

Focusing on the possible adverse effect of COVID-19 vaccine, there are some reports on neurological problems after COVID-19 vaccination. A reversible cerebral vasoconstriction might be observed in some persons receiving inactivated COVID-19 vaccine. The reversible cerebral vasoconstriction is a rare adverse effect of some vaccines such as measles vaccine.[1] For a noninactivated COVID-19 vaccine, it might induce viscosity change and result in a thrombohemostatic disorder.[2] Coagulation risk with the adenoviral vector vaccines is also related to induction of antibody to platelet factor 4.[3] Nevertheless, the pathogenesis of neurological deficit due to inactivated COVID-19 vaccine is unknown.

Regarding the adverse effect due to COVID-19 vaccine, a component of the vaccine might play an important role. In a recent study, the component of COVID-19 vaccine is associated with an allergic adverse effect.[4] Regarding inactivated vaccine, thimerosal is a component that might be related to adverse effect. Thimerosal is a mercury compound used as a composition of inactivated COVID-19 vaccine. It can cause allergic-like reaction at skin.[5] The vasoconstriction effect of thimerosal is also reported,[6] and it might be associated with reversible cerebral vasoconstriction after inactivated COVID-19 vaccination. Further studies on this issue are recommended.

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