I see you're walking to my house driveway When I am drinking my morning coffee You are such a beautiful lady I never seen Hello Is it me you're looking for? I don't know who you are I don't know what you do You don't even wear N95 You're scared the hell out of me I don't know who you are If you're Covid 19 positive All I want to tell you is : I don't like you. 原唱：
I see you're walking to my house driveway
When I am drinking my morning coffee
You are such a beautiful lady I never seen
Hello
Is it me you're looking for?
I don't know who you are
I don't know what you do
You don't even wear N95
You're scared the hell out of me
I don't know who you are
If you're Covid 19 positive
All I want to tell you is : I don't like you.
原唱：
i am covid-19 positive. 你此生仅此一次机会和俺今宵共缠绵。
你，上，还是不上？！
病毒必须数量够多才有威胁，具体见下。
传染性是看滴度的，也就是接触到的病毒越多，被感染的危险性越大（注意：不是绝对会被感染）。
病毒（任何病原体都同理）在进入人体的过程中要经历千难万险。第一关，粘液吸附（比如鼻腔分泌物和泪液）；少数到达彼岸的幸运儿还在观察地形（结合受体进入细胞以前），就被第二关的巡逻免疫细胞吃掉了（一般是巨噬细胞，中性粒细胞之类，不展开）。
如果有的病毒有幸在免疫细胞赶来之前结合受体入侵细胞，那算是成功了一半。被感染的细胞会把有病毒特征的片段放到表面，呼救免疫系统，我被攻击了，快来救我。这时获得性免疫系统就会被激活，B细胞产生抗体，T细胞特异性杀伤。这个过程7-10天。只有以上防线均被攻破，病毒才有可能大量繁殖，造成伤害。
综上：病毒数量是一个因素，自己的免疫力也是决定因素。在免疫力恒定的情况下，降低接触的病毒数量是最有效的防护手段。