Dear editor, thanks for Dr Rujittika Mungunpuntipantip and Dr Viroj Wiwanitkit’s pertinent personal views on the contents of our publication “The effect of COVID-19 vaccination on epileptic seizures in patients with epilepsy: A clinical observation in China,”1 and for their agreeing with the conclusions of the safety of COVID-19 vaccine for PWE.2
Indeed, it is challenging to determine the precise clinical association. It is determined by the limitations of retrospective observational studies, such as that (1) No causal association can be proven; (2) Researchers were not able to control for exposures and interventions; (3) The results depend on the completeness of collected clinical data; (4) The results were subject to influence by biases and confounding factors, and still persisted even with complex statistical adjustments.3 The influence of mental and emotional disorders caused by various factors on the outcome judgment is also one of the potential confounding factors.
Although COVID-19 vaccination is not mandatory in China, the Chinese Center for Disease Control and Prevention has issued uniform technical guidelines for COVID-19 vaccination, which are implemented by health departments and disease control and prevention institutions at all levels.4 Before vaccination, vaccination institutions and physicians are required to complete a survey of the health status, disease history and allergy history of the recipients. At the same time, vaccination contraindications should be included in informed consent and fully informed. In the guidelines, contraindications to vaccination include people who have an ongoing fever, or who have an acute illness, or an acute episode of a chronic disease, or who have an uncontrolled severe chronic disease. The immune response and protective effect of vaccination may be reduced in immunocompromised people. Inactivated vaccine and recombinant subunit vaccine are recommended according to the safety characteristics of previous vaccines of the same type. For adenoidal vector vaccines, it is recommended to be fully informed that individuals weigh the benefits over the risks.
Vaccine-related adverse events are routinely identified based on information obtained through questionnaires designed from the results of previous COVID-19 vaccine clinical trials and medical institution visit records. For the effect of vaccine on epileptic seizures in PWE, questionnaire design and clinical data collection were conducted according to the guidelines or consensus on clinical characteristics, seizure influencing factors and prognostic evaluation of epilepsy published by the International Anti-epileptic League (ILAE). The results were evaluated by two epilepsy specialists to minimize the limitations of the study.
Funding Statement
The authors reported that there is no funding associated with the work featured in this article.
Disclosure statement
No potential conflict of interest was reported by the author.
References
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