Epidemiological characteristics of a local COVID-19 outbreak caused by Omicron variant (BA.2) in Qinzhou, Guangxi
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摘要:
目的 分析广西钦州市一起本地聚集性新型冠状病毒肺炎（COVID-19）疫情的调查处置过程和流行病学特征, 为今后的COVID-19疫情防控工作提供参考。 方法 收集本起疫情病例流行病学和临床表现信息、实验室检测结果和专题分析报告，采用描述性流行病学方法进行分析。 结果 本起COVID-19疫情自2022年3月12—24日共持续13 d，报告感染者97例。 男性49例，女性48例；年龄中位数M（P25，P75）为32岁（17，44.5）；无症状感染者79例，确诊病例18例。 潜伏期中位数为3 d，潜隐期中位数为2 d。 共排查出密接3841人，61人转为感染者，密接续发率1.59%。 明确家庭内传播的疫情共8起，家庭续发率为65%（95%CI：20%～100%）；涉及3起大规模聚集性疫情：娱乐会所包厢内聚集、婚礼聚餐、新居宴聚餐，罹患率分别为63.64%、9.38%、12.16%。 疫情首先在娱乐会所包厢内暴发，最长的传播链至少传至5代。 病毒基因测序显示为奥密克戎BA.2变异株。 结论 通过对一起新型冠状病毒奥密克戎BA.2变异株引起的聚集性疫情分析发现，早期采取措施对控制疫情有重要意义。 -
关键词:
- 新型冠状病毒肺炎 /
- 奥密克戎变异株BA.2 /
- 防控策略 /
- 流行病学特征
Abstract:Objective To analyze the epidemiological characteristics of a local COVID-19 outbreak in Qinzhou, Guangxi Zhuang autonomous region, and provide reference for the prevention and control of COVID-19 in the future. Methods The epidemiological and clinical information, analysis reports and laboratory test results of the COVID-19 cases were collected for a descriptive epidemiological analysis. Results A total of 97 COVID-19 cases, including 79 asymptomatic cases and 18 confirmed cases, were reported in Qinzhou during 12−24 March, 2022. Forty nine cases were males and 48 cases were females. The median of age of the cases was 32 (17.0, 44.5) years. The median of incubation period was 3 days. The median of latent period was 2 days. A total of 3841 close contacts were screened, in whom 61 were infected. The secondary attack rates in 3841 close contacts was 1.59%. The secondary attack rate in household contacts was 65% in 8 family clustering (95% CL: 20%−100%). Three mass gathering were identified in a local recreation center box, a wedding ceremony and a family feast for new home, in which the attack rates were 63.64%, 9.38% and 12.16%, respectively. Transmission firstly occurred in the people attending the activity in the recreation center box. At least 5 generations of transmission were identified in the outbreak. The results of genome second generation sequencing of the isolates from 20 infection cases revealed that the pathogen of the outbreak was SARS-CoV-2 Omicron variant (BA.2). Conclusion Analysis on the cases caused by Omicron variant (BA.2) indicated early prevention measures are important for the control of further spread of COVID-19. -
图 1 每日报告病例情况
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Figure 1. General information of daily reported cases
图 2 97例感染者传播链示意图
注: 1. 序号按报告先后顺序，如1号为首发病例。2.实心圆圈标注的1、2、3、4、8、17、33、36. 60号共9名感染者样本得到完整的全基因组序列。3. 各代感染者出现时间为初筛阳性时间
Figure 2. Diagram of chain transmission of 97 infections
表 1 8例单次暴露、暴露时间明确的感染者潜伏期和潜隐期一览表
Table 1. Incubation period and latent period of 8 infection cases with single exposure and accurate exposure time
病例序号 诊断 暴露时间 阳性时间 最后一次阴性检测时间 发病时间 潜隐期（d） 潜伏期（d） 首发症状 40 无症状感染者 3月13日 3月15日 3月14日 − 2 − − 49 无症状感染者 3月13日 3月15日 3月14日 − 2 − − 56 无症状感染者 3月15日 3月17日 3月16日 − 2 − − 37 无症状感染者 3月12日 3月15日 3月14日 − 3 − − 95 无症状感染者 3月18日 3月21日 3月20日 − 3 − − 28 确诊病例 3月12日 3月15日 − 3月14日 − 3 发热 29 确诊病例 3月12日 3月15日 − 3月15日 − 3 发热 50 确诊病例 3月13日 3月16日 − 3月16日 − 3 发热 注：–. 无此项 
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表 2 1号病例样本SARS-CoV-2基因组核苷酸与参考序列变异情况比对表
Table 2. Comparison of nucleotide mutation of SARS-CoV-2 genome sequence from index case and reference sequences
毒株名称 共同变异位点（个）a 共同变异位点 共同变异位点 不同变异位点 合计 hCoV-19/Guangxi/import018/2022 66 66 hCoV-19/Guangxi/import017/2022 66 T22882G 67 SARS-CoV-2/human/USA/CA-CDC-STM-XQKCU2UPB/2022 66 T22882G A19812G A16474G 69 hCoV-19/GuangXiQZ/local-1/2022 66 T22882G A19812G A8031G、C16637G 70 注：a. 包括C241T、T670G、C2445T、C2790T、C3037T、G4184A、C4321T、C9344T、A9424G、C9534T、C9866T、C10029T、C10198T、G10447A、C10449A、C12880T、C14408T、C15714T、C17410T、A18163G、C19955T、A20055G、C21618T、G21987A、T22200G、G22578A、C22674T、T22679C、C22686T、A22688G、G22775A、A22786C、G22813T、G22992A、C22995A、A23013C、A23040G、A23055G、A23063T、T23075C、A23403G、C23525T、T23599G、C23604A、C23854A、G23948T、A24424T、T24469A、C25000T、C25584T、C26060T、C26270T、C26577G、G26709A、C26858T、A27259C、G27382C、A27383T、T27384C、C27807T、A28271T、C28311T、G28881A、G28882A、G28883C、A29510C
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[1] 季倩婷, 尚浩天, 施泽灿, 等. 新型冠状病毒疫苗的研究策略及应对奥密克戎等变异株的挑战[J]. 病毒学报,2022,38(4):937–948. DOI: 10.13242/j.cnki.bingduxuebao.004121.Ji QT, Shang HT, Shi ZC, et al. Research strategies of COVID-19 vaccines and challenges towards Omicron variant[J]. Chin J Virol, 2022, 38(4): 937–948. DOI: 10.13242/j.cnki.bingduxuebao.004121. [2] WHO. Coronavirus disease (COVID-19) pandemic[EB/OL]. (2022-09-19)[2022-09-19]. https://www.who.int/europe/emergencies/situations/covid-19. [3] WHO. Tracking SARS-CoV-2 variants[EB/OL]. (2022)[2022−09−16]. https://www.who.int/en/activities/tracking-SARS-CoV-2-variants. [4] 冯晔囡, 夏影, 陈操, 等. 新型冠状病毒全球主要流行株基因组变异变迁分析[J]. 疾病监测,2021,36(10):990–995. DOI: 10.3784/jbjc.202109150506.Feng YN, Xia Y, Chen C, et al. Analysis on genome variation of SARS-CoV-2 circulating in the world[J]. Dis Surveill, 2021, 36(10): 990–995. DOI: 10.3784/jbjc.202109150506. [5] He XM, Hong WQ, Pan XY, et al. SARS-CoV-2 omicron variant: characteristics and prevention[J]. MedComm, 2021, 2(4): 838–845. DOI: 10.1002/mco2.110. [6] U. S. Department of Health & Human Services. Omicron variant: what you need to know[EB/OL]. (2021-08-11)[2022-09-19]. https://www.cdc.gov/coronavirus/2019-ncov/variants/omicron-variant.html. [7] Singhal T. The emergence of Omicron: challenging times are here again![J]. Indian J Pediatr, 2022, 89(5): 490–496. DOI: 10.1007/s12098−022−04077−4. [8] Vitiello A, Ferrara F, Auti AM, et al. Advances in the Omicron variant development[J]. J Intern Med, 2022, 292(1): 81–90. DOI: 10.1111/joim.13478. [9] 国务院应对新型冠状病毒肺炎疫情联防联控机制综合组. 关于印发新型冠状病毒肺炎防控方案(第八版)的通知[EB/OL]. (2021-05-11)[2022-06-21]. http://www.gov.cn/xinwen/2021-05/14/content_5606469.htm.Comprehensive Group for Joint COVID-19 Prevention and Control Mechanism of the State Council. Notice of publishing “COVID-19 prevention and control protocol” (8th edition)[EB/OL]. (2021−05−11)[2022-06-21]. http://www.gov.cn/xinwen/2021-05/14/content_5606469.htm. [10] 曾光, 李辉, 廖苏苏. 现代流行病学与中国应用[M]. 北京: 中国协和医科大学出版社, 2021: 691−700.Zeng G, Li H, Liao SS. Modern epidemiology and its application in China[M]. Beijing: Peking Union Medical College Press, 2021: 691–700. [11] Meo SA, Meo AS, Al-Jassir FF, et al. Omicron SARS-CoV-2 new variant: global prevalence and biological and clinical characteristics[J]. Eur Rev Med Pharmacol Sci, 2021, 25(24): 8012–8018. DOI: 10.26355/eurrev_202112_27652. [12] Thakur V, Ratho RK. OMICRON (B. 1.1. 529): a new SARS-CoV-2 variant of concern mounting worldwide fear[J]. J Med Virol, 2022, 94(5): 1821–1824. DOI: 10.1002/jmv.27541. [13] 吴俣, 刘民. 不同新型冠状病毒变异株感染的COVID-19潜伏期研究[J]. 中国全科医学,2022,25(11):1309–1313,1319. DOI:10.12114/j.issn.1007−9572.2022.0078.Wu Y, Liu M. The incubation period of COVID-19 caused by different SARS-CoV-2 variants[J]. Chin Gen Pract, 2022, 25(11): 1309–1313,1319. DOI: 10.12114/j.issn.1007−9572.2022.0078. [14] Madewell ZJ, Yang Y, Longini Jr IM, et al. Factors associated with household transmission of SARS-CoV-2: an updated systematic review and meta-analysis[J]. JAMA Netw Open, 2021, 4(8): e2122240. DOI: 10.1001/jamanetworkopen.2021.22240. [15] 程悦, 刘竹, 龙露, 等. 成都市新冠肺炎聚集性疫情流行病学与病原基因特征[J]. 中国公共卫生,2022,38(6):752–757. DOI: 10.11847/zgggws1136549.Cheng Y, Liu Z, Long L, et al. Epidemiology and viral genomic characteristics of COVID-19 clustering epidemics of in Chengdu city[J]. Chin J Public Health, 2022, 38(6): 752–757. DOI: 10.11847/zgggws1136549. [16] 张翔宇, 王廉皓, 王雪纯, 等. 新型冠状病毒传播模式研究[J]. 疾病监测,2022,37(6):740–744. DOI: 10.3784/jbjc.202203210108.Zhang XY, Wang LH, Wang XC, et al. Research on transmission pattern of SARS-CoV-2[J]. Dis Surveill, 2022, 37(6): 740–744. DOI: 10.3784/jbjc.202203210108. [17] 周燕, 肖建鹏, 胡建雄, 等. 我国常态化防控阶段的新型冠状病毒肺炎本土疫情流行特点和防控经验[J]. 中华流行病学杂志,2022,43(4):466–477. DOI:10.3760/cma.j.cn112338−20211217−00995.Zhou Y, Xiao JP, Hu JX, et al. Epidemiological characteristics of local COVID-19 epidemics and control experience in routine prevention and control phase in China[J]. Chin J Epidemiol, 2022, 43(4): 466–477. DOI: 10.3760/cma.j.cn112338−20211217−00995. -
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