評估5-11歲兒童接種科興疫苗的成效與風險(三)

 

來自港大化學系博士Dr. K. Kwong的看法

 

兒童的免疫系統尚未成熟,因此難以預計身體對外物的反應。如果免疫系統反應不足,病毒就容易高速繁殖,後果難以估量;如果身體反應過於強烈,就會產生過敏反應,需要使用抗組織胺藥。

 

選擇不接種疫苗:

在身體強壯 + 有足夠休息下,如果兒童接觸到Omicron(通常只造成上呼吸道感染),很大機會只會有感冒症狀;但如果遇上Delta(容易造成下呼吸道感染),病情會相對嚴重,處理亦較為麻煩。

 

針頭打進血管時:

兩種疫苗均有危險性。當疫苗經血液進入身體器官,那些器官就會發生免疫反應,造成發炎;若發炎情況於血管發生,免疫複合物或造成血管堵塞,後果嚴重。

 

 

Bring Home Messages

 

就着科興疫苗對兒童防疫的成效及風險,以上陳列了不同研究發現/專家評價,各位可自行斟酌是否讓小朋友注射此疫苗,同時亦歡迎其他資訊的補足,或不足之處的指正,筆者不勝感激。

 

事實上,任何接觸病毒的機會亦能達至注射疫苗的效果,而發病與否在於免疫系統是否足夠強大(Paludan & Mogensen, 2022),繼而控制病毒擴散 & 消滅病毒。根據外國研究(Conti, M.G. et. al, 2021),即使是初生嬰兒,其免疫系統也能經由母乳餵哺(研究中的母親在分娩前後曾感染肺炎病毒)被間接教育去辨認 & 消滅肺炎病毒。

 

最後,文首及文中提及接種復必泰疫苗的建議。這些論述或揭示了在疫苗選擇和劑量上,靈活性其實比想像中高。兒童的免疫系統尚未發展成熟,因此與大人的防疫方向會有差異;在選擇疫苗時,不妨先參考更多有關疫苗比較的最新資訊。

 

 

Reference

 

明報(2021, Nov 16)【新冠疫苗】疫苗顧問專家委員會建議:3至17歲可打科興 復必泰門檻降至5至11歲(附兒童接種兩款疫苗副作用一覽)https://health.mingpao.com/%E7%96%AB%E8%8B%97%E9%A1%A7%E5%95%8F%E5%B0%88%E5%AE%B6%E5%A7%94%E5%93%A1%E6%9C%83%E5%BB%BA%E8%AD%B0-3%E8%87%B317%E6%AD%B2%E5%8F%AF%E6%89%93%E7%A7%91%E8%88%88-%E5%BE%A9%E5%BF%85%E6%B3%B0%E9%96%80/

 

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CDC. (2022, Jan 7). Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Approved or Authorized in the United States. https://www.cdc.gov/vaccines/covid-19/clinical-considerations/covid-19-vaccines-us.html

 

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