2019新型冠狀病毒比別的病毒更頻繁的突變，但是差別都不大，一直到D614G出現。
什麼是D614G？
作者：SPQR10Binte altaf, CC BY-SA
它的突變發生地點在614，它影響的是病毒上的棘蛋白。這裡的突變能比較容易接上被感染者的接收器，使得人比較容易被感染。
它什麼時候突變的？
其實在疫情一開始時，它就已經突變了，歐、美大部分的人都是受到D614G的感染。所以研究發現它已是現在世上最流行的一支2019新型冠狀病毒了。
它會不會讓人病得更嚴重？
雖然它傳染力變強，但現在研究並沒有發現它會讓人病得更嚴重。
那為什麼我們要那麼緊張？
我們會緊張，是因為它已經開始出現在東南亞了，包括菲律賓和馬來西亞。而D614G這支病毒比原本在亞洲傳播的病毒，傳染力要強了許多，所以如果D614G在東南亞擴散開來，預期東南亞各國的傳染率將要大大升高。
它會不會影響疫苗的研發？
雖然突變處可能會影響免疫系統對病毒的偵察能力，但是現在的研究結論認為它不影響整個病毒結構，所以應該不會影響疫苗的發展進度。
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