Delta变异株超短偷袭与超长逃逸及其防控——以真实案例探讨新型冠状病毒传播的预防与阻击  

The strategy to overcome attack with an ultra-short incubation period and escape with an ultra-long incubation period of the COVID-19 Delta variant of based on cases of outbreaks and their containment

作　　者：卓家同[1] ZHUO Jia-tong(Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention,Nanning,Guangxi 530028,China)

机构地区：[1]广西壮族自治区疾病预防控制中心,广西南宁530028

出　　处：《上海预防医学》2021年第9期869-874,共6页Shanghai Journal of Preventive Medicine

摘　　要：【目的】探讨包括Delta变异株在内的新型冠状病毒肺炎疫情(简称“新冠疫情”)防控与阻击策略。【方法】以普通株新冠疫情(大连2020年12月15日俄罗斯籍货轮冷链物品搬运引发的新冠疫情)和Delta变异株新冠疫情(2021年5月20日及6月23日广州涉外相关新冠疫情)作对比,分析其传播速度。【结果】新冠Delta变异株第一代潜伏期为4 d,较新冠普通株(9 d)短5 d,Delta变异株从密接到传染天数为2~4 d,短于普通株从密接到传染天数(3~6 d);以体液免疫为主的传统灭活疫苗回忆反应需要8 d才发挥免疫作用,而mRNA疫苗回忆反应需要4 d才发挥免疫作用,新冠病毒存在的超短潜伏期可抢在疫苗发挥免疫作用之前进行偷袭,同时也存在14 d以上超长潜伏期逃逸物理隔离而引发的局部疫情。【结论】新冠Delta变异株从第二代到第四代逐代传染他人时各代均比普通株快1/3 d,疫苗接种加物理隔离和外出全程佩戴口罩三管齐下是应对包括新冠病毒Delta变异株(或其他变异株)在内的加速传代及超短潜伏期偷袭与超长潜伏期逃逸的策略和措施。[Objective]To discuss the strategy of fighting and containing COVID-19.[Method]The speed of the spreading of the ordinary strain in Dalian on Dec.15,2021 caused by carrying cold-chain goods from a Russia-registered freighter and the Delta strain caused by imported cases in Guangzhou during May 20 to Jul.23,2021 was compared.[Results]The incubation period of the first generation of the imported Delta strain of COVID-19 was 4 days,which was 5 days shorter than that of the ordinary strain of COVID-19;The time from the exposure to the Delta strain to spreading to the next person was 1/3 days shorter than that of the ordinary strain of COVID-19.The inactivated vaccine needs at least 8 days for recall immune response meanwhile the mRNA vaccine needs at least 4 days,which could not completely block the COVID-19 virus,especially the Delta strain,which can attack with an ultra-short incubation period.Meanwhile,some COVID-19 strains have an incubation period longer than 14 days,which was another reason for the outbreak.[Conclusion]The time from the exposure to the COVID-19 Delta strain to spreading to the next person is 1/3 day shorter that of the ordinary strain of COIVD-19.Measures of full vaccination,physical quarantine and wearing masks in public should be taken to fight the epidemic of COVID-19,especially the Delta strain(or other variants)with an ultra-short or an ultra-long incubation period which can escape quarantine.

关 键 词：新冠病毒肺炎疫情 Delta变异株 疫苗接种 物理隔离 佩戴口罩 

分 类 号：R13[医药卫生—劳动卫生]