2. 關於疫苗，很好奇效果到底能有多大？大家都知道Influenza Viruses每年流行的Strains不同，生產疫苗一半要靠猜，所以打了疫苗也不一定完全保險，對嗎？同理，雖然感染後自身有了抗體，但病毒傳了幾輪後變異了，會不會再次感染？
這個問題朋友剛回複了我，copy過來：These viruses "are still so genetically similar that these mutations shouldn't alter a new vaccine," Grubaugh said. It's "unlikely that the developers have to worry about this." Once the vaccine is out, however, the virus could adapt to it and develop resistance, he said, but considering that other RNA viruses — such as those that cause measles, mumps and yellow fever — didn't develop resistance to vaccines, that scenario is unlikely. https://www.google.ca/amp/s/www.livescience.com/amp/coronavirus-mutations.html
但是流感病毒也是RNA病毒，流感疫苗為啥不那麽有效呢？
3. 這病毒是SARS2，會不會象SARS一樣自己消失？
希望專家能幫助解惑。謝謝。
