zh-cn	新型冠状病毒肺炎流行病学调查指南
en-us	Guidelines for COVID-19 Epidemiological Investigations

zh-cn	为指导各地疾控机构规范开展新型冠状病毒肺炎的流行病学调查工作，掌握病例发病情况、暴露史、接触史等流行病学相关信息，分析聚集性疫情的传播特征和传播链，做好密切接触者 的追踪判定，防范新型冠状病毒肺炎疫情的蔓延和传播，特制定本指南。
en-us	These guidelines are based on the most recent research on the epidemiology of COVID-19 from home and abroad and are intended to further improve epidemiological investigations of COVID-19 cases to control spread of the virus.

zh-cn	调查病例的传染源，追踪和判定密切接触者；
en-us	To investigate source of infection and trace and identify close contacts;

zh-cn	调查病例的发病和就诊情况、临床特征和危险因素等；
en-us	To investigate onset of illness and treatment of patients, including clinical characteristics and risk factors;

zh-cn	调查分析聚集性疫情的传播特征和传播链。
en-us	To investigate and analyze transmission characteristics of COVID-19 cases and clusters of cases.

zh-cn	调查对象
en-us	Scope

zh-cn	新型冠状病毒肺炎疑似病例、确诊病例和无症状感染者，以及聚集性疫情。
en-us	The guidelines cover investigation of COVID-19 suspected cases, confirmed cases, asymptomatic infected persons, and clusters of cases.

zh-cn	个案调查
en-us	Case Investigation

zh-cn	县（区）级疾控机构接到报告后，应当于 24 小时内完成初次流行病学调查，
en-us	The county (district) level disease control and prevention agency, upon receiving a report of one or more COVID-19 cases, should complete an initial epidemiological investigation within 24 hours.

zh-cn	可通过查阅资料、询问病例、知情人和接诊医 生等方式开展。
en-us	The investigation can be conducted through review of documents and interviews with patients, physicians, acquaintances, and others as needed.

zh-cn	在出院病例完成 14 天隔离管理和健康状况监测后，尽量补充收集填报病例样本采集与检测信息。
en-us	When a patient has completed a 14-day period of isolation and health monitoring, the county (district) level disease control and prevention agency should obtain information on specimen collection and testing for inclusion in the case report.

zh-cn	个案调查主要调查疑似病例、确诊病例和无症状感染者的基本信息、发病与就诊、危险因素与暴露史、实验室检测情况等，
en-us	Case investigation should include basic demographic and identification data and information on onset of symptoms, care-seeking behavior, risk factors, potential exposures, and laboratory findings of suspected cases, confirmed cases, and asymptomatic infected persons.

zh-cn	填写个案调查表，其中疑似病例仅填写病例的姓 名、性别、身份证号等基本信息。
en-us	For suspected cases, this information is to be recorded in a Case Investigation Questionnaire  that includes identifying information such as name, gender, and ID number.

zh-cn	同时，追踪调查、判定病例的 密切接触者，填写密切接触者医学观察健康状况监测个案表，详 见《新型冠状病毒肺炎病例密切接触者调查与管理指南》。
en-us	Information about individuals identified as close contacts should be recorded in the Health Status Monitoring Case Form for Close Contacts in the Guideline for Investigation and Management of Close Contacts of COVID-19 Cases.

zh-cn	聚集性疫情调查。
en-us	Investigations on Clusters of Cases

zh-cn	县（区）级疾控机构根据网络直报信息和病例个案调查情况， 对符合定义的聚集性疫情立即开展调查。
en-us	Based on case reports in the Infectious Disease Reporting Information Management System (IDRIMS) and case investigation findings potentially meeting the above definition, the county (district) level disease control and prevention agency should immediately launch an investigation into a possible cluster of cases.

zh-cn	调查内容包括病例的感染来源、密切接触者等信息，
en-us	Investigations should include information on source of infection and close contacts.

zh-cn	重点调查病例间的流行病学联系， 分析传播链和传播途径，调查与分析方法见附件 2。
en-us	The investigation should focus on epidemiological links among cases; chains of transmission and transmission routes should be analyzed. For investigation and analytic methods, refer to Appendix S2.

zh-cn	组织与实施
en-us	Organization and Implementation

zh-cn	按照“属地化管理”原则，由病例就诊医疗机构所在的县（区） 级卫生健康行政部门组织疾控机构开展新型冠状病毒肺炎病例 的流行病学调查。
en-us	Using the principle of “localized management,” health authorities of the county or district where the individual being investigated sought medical care shall have the disease control and prevention agency conduct an epidemiological investigation of the case or cluster of cases.

zh-cn	调查单位应当迅速成立现场调查组，明确调查 目的，制定调查计划，确定调查组人员及职责分工。
en-us	The investigating agency should promptly establish an investigation team, clarify the purpose of the investigation, develop an investigation plan, select team members, and assign duties and tasks.

zh-cn	调查期间， 调查人员要做好个人防护。
en-us	During all investigations, investigators should use proper personal protective equipment.

zh-cn	市级、省级、国家级疾病预防控制中 心可根据疫情处理需要赶赴现场，参与开展流行病学调查。
en-us	Professionals from disease control and prevention agencies at the prefecture, provincial, and national levels should accompany county or district level teams when requested or when deemed necessary.

zh-cn	信息的上报与分析
en-us	Analysis and Reporting

zh-cn	县（区）级疾控机构完成确诊病例、无症状感染者个案调查 或聚集性疫情调查后，将个案调查表和调查报告及时通过网络报 告系统进行上报。
en-us	Upon completion of an investigation of confirmed cases, asymptomatic infected persons, or cluster of cases, the county (district) level disease control and prevention agency should submit a case investigation form or investigation report to the online reporting system.

zh-cn	各地应对流行病学调查信息质量进行审核，并 根据调查进展及时补充和订正相关信息。
en-us	The local CDC should review the submitted report and update it in a timely manner as the investigation progresses.

zh-cn	聚集性疫情调查结果按照《国家突发公共卫生事件相关信息报告管理工作规范（试行）》的要求，填报事件的基本信息、初 次、进展和结案报告，
en-us	For investigations of clusters of cases, all basic information and all initial, interim, and final reports should be submitted in accordance with the National Protocol for Reporting and Management of Public Health Emergency Related Information (Trial).

zh-cn	并将聚集性疫情病例关键信息（参见附件2）附在结案报告中。
en-us	All key information of these investigations (see Appendix S2) should be included in the final report.

zh-cn	新型冠状病毒肺炎聚集性疫情调查与分析方法
en-us	Investigation and Analytic Methods for Clusters of COVID-19 Cases

zh-cn	聚集性疫情定义
en-us	Definition of cluster of cases

zh-cn	聚集性疫情是指 14 天内在小范围（如家庭、办公室、 学校班级、车间等）发现 2 例及以上的确诊病例或无症状感 染者，且存在人际传播的可能性，或共同暴露而感染的可能 性。
en-us	A cluster of cases refers to the detection of 2 or more confirmed  cases or asymptomatic infected persons in a small area (e.g., in a family, an office, a school class, or workplace) within a 14-day period and that has the possibility of person-to-person transmission or a common exposure.

zh-cn	聚集性疫情发现
en-us	Detection

zh-cn	通过病例的个案调查，查找有密切接触或共同暴 露史的确诊病例、疑似病例或无症状感染者。
en-us	Through case investigation, find confirmed cases, suspected cases, and asymptomatic infected persons who have had close contact with a case or who may have had a common exposure with a case.

zh-cn	在中国疾病预防控制信息系统，查找同单位或同 住址，且发病间隔在1至2个潜伏期内的确诊病例、疑似病 例或无症状感染者。
en-us	Through the Infectious Disease Reporting Information Management System (IDRIMS), search for confirmed cases, suspected  cases, and asymptomatic infected persons working for the same employer, or those who have the same address and whose date of illness onset was within 1 or 2 incubation periods.

zh-cn	汇总分析个案流调报告，查找不同地区、在发病 前 14 天内均有乘坐同一航班和火车车次，或参加相同旅行 团或会议等具有共同暴露史的确诊病例、疑似病例或无症状 感染者。
en-us	Through consolidating and reviewing case investigation  reports, search for confirmed  cases, suspected cases, and asymptomatic infected persons from different regions with the same exposure history, such as taking the same flight or train, or participation in a common travel group or attended a common conference within 14 days before onset of illness.

zh-cn	调查内容
en-us	Investigation content

zh-cn	病例和密切接触者调查
en-us	Patients and close contact

zh-cn	聚集性疫情相关病例的调查应重点关注：
en-us	The investigation of clusters of cases should focus on:

zh-cn	病例及密切 接触人员有无武汉市及周边地区，或境内其他有病例报告社 区，或境外疫情严重国家或地区的旅行或居住史；
en-us	whether the patients and close contacts have a history of travel to or residence in Wuhan and its surrounding areas, other domestic communities with reported cases, or overseas countries or regions with severe outbreaks;

zh-cn	是否接 触过来自武汉市及周边地区，或境内其他有病例报告的社区，或境外疫情严重国家或地区的发热或有呼吸道症状的患者；
en-us	whether they have been in contact with patients with fever or respiratory symptoms from Wuhan and its surrounding areas, other domestic communities with reported cases, or overseas countries or regions with severe outbreaks;

zh-cn	接触类型、接触距离、频率及采取的个人防护措施情 况等；
en-us	the type of contact, contact distance, frequency of occurrence, and personal protective measures taken;

zh-cn	病例相关活动轨迹；
en-us	case-related activity tracking; and

zh-cn	核实并登记病例姓名、身份 证号码及联系电话。
en-us	verification and registration of the name, ID number, and contact details of patients.

zh-cn	初始调查时，聚集性疫情相关病例的时间范围可不限于14 天，
en-us	For the initial investigation, the time period for clusters of cases should not be limited to 14 days.

zh-cn	相关疑似病例和无症状感染者也需纳入调查。
en-us	The relevant suspected cases and asymptomatic infected persons should be included in the investigation.

zh-cn	结案时， 应根据流行病学和实验室调查做出是否为聚集疫情相关病 例的最终判定。
en-us	When the investigation is closed, a final determination should be made whether it was a cluster of cases based on epidemiological and laboratory findings.

zh-cn	密切接触者调查时应重点关注：
en-us	The investigation of close contacts should focus on:

zh-cn	密切接触者发病、标 本采集和检测情况；
en-us	the onset of symptoms and specimen collection and testing of close contacts;

zh-cn	密切接触类型，如聚餐、家庭共同生 活、同乘交通工具等；
en-us	the types of close contacts, such as having meals together, living in the same household, sharing transportation, etc.; and

zh-cn	密切接触者转归情况。
en-us	the health outcome of close contacts.

zh-cn	病例暴露场所调查。
en-us	Place of exposure

zh-cn	家庭暴露：调查病例共同居住的家庭成员人数、接触 及个人防护情况；
en-us	Family exposures: investigate the number of family members living together and their contacts and personal protection;

zh-cn	家庭环境，包括房间数、面积和通风与空 调使用情况，洗手设施情况；
en-us	the household environment, including number of rooms, floor area, ventilation and air conditioning use, and hand washing facilities;

zh-cn	单元楼的电梯使用及消毒情况 等。
en-us	and elevator use and status of building disinfection.

zh-cn	聚餐暴露：调查聚餐时间、地点和人员及座位分布， 聚餐环境、通风与空调使用情况、洗手设施情况，可能导致 传播风险增加的行为等。
en-us	Mealtime exposures: investigate the time, place, attendees and seating arrangements, dining environment, ventilation and air conditioning use, hand washing facilities, and behaviors that may lead to increased risk of transmission.

zh-cn	集体单位：调查病例所在工作场所的人员数量、工位 分布、车间分布、工作接触方式及工作人员防护情况，工作 场所、食堂、宿舍、卫生间等相关场所的环境卫生、中央空 调、新风系统使用与通风情况、洗手设施情况，电梯使用及 消毒情况。
en-us	Business exposures: investigate the number of workers; the distribution of work stations; the distribution of workshops; the type of work contact and the protection of workers in the workplace; the environmental health of the workplace, canteen/cafeteria,  dormitory, toilet, and other relevant places; use of central air conditioning, air cleaning or circulation systems, and ventilation; hand washing facilities; elevator use; and disinfection.

zh-cn	交通工具：调查乘坐的交通工具种类、座位分布、通风和空调使用及消毒情况、洗手设施情况，同乘人员数量、 健康状况和个人防护情况等。
en-us	Means of transportation: investigate the means of transportation, seat distribution, ventilation and use of air conditioning, disinfection status, hand washing facilities,  number of passengers,  health conditions, and use of personal protective equipment.

zh-cn	公共场所：病例暴露于商场、超市、公共浴池、酒店、 养老院、医院、婚礼/葬礼现场等公共场所的停留时间，人 员数量或密集程度及个人防护情况，公共场所布局与面积、 通风和空调使用情况、电梯使用及消毒情况、洗手设施情况 等。
en-us	Public places: the length of stay in shopping malls, supermarkets, public baths, hotels, nursing homes, hospitals, wedding/funeral sites, and other public places where patients may have been exposed; number and density of people; personal protection; layout and floor area of public places; use of ventilation and air conditioning; use and disinfection of elevators; and hand washing facilities.

zh-cn	采样与检测。
en-us	Sampling and testing

zh-cn	所有病例应按照相关要求开展标本采集与检测。
en-us	Specimen collection and testing should be done for all cases in accordance with relevant requirements.

zh-cn	聚集性疫情的首例病例、怀疑为无症状感染者或潜伏期内传播等特殊情形，
en-us	For special circumstances such as the index case of a cluster of cases, people suspected to be asymptomatically infected, or patients having transmitted during the incubation period, increase the frequency of sampling and testing.

zh-cn	在两次核酸检测阴性的情况下，建议增加采样和检测频次，并采集发病后 7 天内和 3-4 周后的双份血清标本留存备查。
en-us	Use of two negative nucleic acid tests rather than relying on a single negative test, and collecting two serum specimens within 7 days and between 3-4 weeks after onset is recommended for future reference in these special circumstances.

zh-cn	资料分析
en-us	Information analysis

zh-cn	病例传播链分析。
en-us	Analysis of transmission chains

zh-cn	根据病例发病时间绘制流行曲线，
en-us	Draw epidemic curves according to the onset time of cases.

zh-cn	结合与首例病例的关 系、发病前14天暴露史及发病后的活动轨迹，
en-us	Draw the onset time sequence diagram or case relationship diagram  with information including the relation with the index case, the exposure history up to 14 days before onset and activities after onset of illness.

zh-cn	绘制发病时序图或病例关系图，分析传播链。
en-us	Once completed, the transmission chain should be thoroughly analyzed in view of all available information.

zh-cn	病例代际分析。
en-us	Analysis of Generation of Infection

zh-cn	根据流行曲线、时序图或病例关系图，结合潜伏期、暴露史，逐一判断病例代际。
en-us	According to the epidemic curve, time sequence diagram, case relationship diagram, information of incubation period, and exposure history, determine the generation of each case.

zh-cn	每起聚集性疫情的代际判定可参照以下原则：
en-us	The following principles can be referred to in determining the generation of each case.

zh-cn	第一代病例通常为发病时间最早的病例，即聚集性疫情的首例。
en-us	The first generation is usually the case with the earliest onset, i.e. the index case of a cluster of cases.

zh-cn	如果怀疑存在无症状感染者或潜伏期传染的情况，均需结合流行病学调查和实验室检测结果进行综合分析判定。
en-us	If asymptomatic infected  persons  or  transmission during  the  incubation  period  is  suspected, comprehensive analysis and determination should be based on epidemiological investigation and laboratory testing results.

zh-cn	第二代病例判定原则上符合以下三个条件：
en-us	In principle, the following three criteria should be met for determining the second generation of cases:

zh-cn	发病前 14 天内仅与第一代病例有过接触史；
en-us	history of contact with the first generation case within 14 days before onset of illness;

zh-cn	未曾到过或居住在武汉 市及周边地区，或境内其他有病例报告的社区，或境外疫情 严重的国家或地区；
en-us	within 14 days before onset, the patient has never visited or lived in Wuhan and surrounding areas, in other domestic communities with reported cases, or in overseas countries or regions with severe outbreaks;

zh-cn	无医院就诊等其他可疑暴露史，或所 在地区未发生明显的社区传播。
en-us	within 14 days before onset, there was no other suspected exposure history, such as visiting a hospital or a community with ongoing virus transmission.

zh-cn	第三代及以上病例判定可参照二代病例判定原则。
en-us	These three criteria for determining the second generation of cases can also be used for identifying third generation cases.

zh-cn	若病 例在发病前 14 天内与前两代病例均有接触，则代际无法判断。
en-us	If the patient has been in contact with the previous two generations within 14 days before onset, the generation cannot be confirmed.

zh-cn	潜伏期分析。
en-us	Analysis of the incubation period

zh-cn	对单个病例准确计算潜伏期应符合以下三个条件：
en-us	The following three criteria should be met to accurately calculate the incubation period for a single case:

zh-cn	二代病例与首例病例有明确的接触史；
en-us	the second-generation  case has a clear contact history with the index case;

zh-cn	二代病例与首例病例 接触时间较短；
en-us	the second-generation  case has had at least some short contact time with the index case;

zh-cn	二代病例除与首例病例接触之外，在发病 前无任何其他相关暴露史或接触史。
en-us	the second-generation  case has no other exposure history or contact history before onset other than with the index case.

zh-cn	在聚集性疫情中，若发现单个病例的潜伏期超过现有研 究的最短和最长潜伏期范围异常值，应核实是否符合上述条 件，确认病例发病时间和与首例接触时间的准确性。
en-us	In a cluster outbreak, if the incubation period of a single case is found to have exceeded the minimal and maximal value observed in existing studies, verifying whether the above criteria are met and confirm the accuracy of the onset time of the patient's illness and the contact time with the index case.

zh-cn	潜伏期传染性分析。
en-us	Analysis of infectivity during incubation

zh-cn	在聚集性疫情中，若判定首例存在潜伏期传播，需满足 以下三个条件：
en-us	In a cluster outbreak, if the index case is determined to have been infective during the incubation period, the following three criteria should be met:

zh-cn	首例与二代病例接触时均无任何临床症状 或体征，且二者发病后无接触史；
en-us	the index case and the second-generation  case did not have any clinical symptoms or signs of infection at the time of contact, and there was no contact history between these two cases after onset;

zh-cn	二代病例在末次接触首 例后 14 天内发病；
en-us	the onset of illness for the second-generation  case happened within 14 days after the last contact with the index case;

zh-cn	二代病例除与首例接触外，无其他相关暴露史或接触史。
en-us	the second-generation  case had no other exposure history or contact history other than that with the index case.

zh-cn	建议调查时，首例应尽早采样，若首例阳性标本的采样 时间早于二代病例的发病时间，则证据更强。
en-us	It is recommended that sampling be done as early as possible for the index case during the investigation. If the sampling of the positive specimen of the index case is earlier than the onset of the second-generation case, the evidence is considered to be stronger.

zh-cn	此外，还建议 采集首例发病后 7 天内和 3-4 周后的双份血清标本留存备 查。
en-us	In addition, it is recommended to collect two serum specimens within 7 days and between 3-4 weeks after onset of illness of the index case for future reference.

zh-cn	无症状感染者传染性分析。
en-us	Analysis of infectivity of asymptomatic infected persons

zh-cn	在聚集性疫情中，若判定无症状感染者为传染源，需满 足以下三个条件：
en-us	In a cluster of cases, if an asymptomatic infected person is determined to be the source of infection, the following three conditions should be met:

zh-cn	无症状感染者与二代病例有明确的接触 史，且二代病例发病后与该无症状感染者无接触史；
en-us	the asymptomatic infected person and the second-generation  case have a clear contact history, and the second-generation case, after his/her onset of illness, has no history of contact with the asymptomatic infected person;

zh-cn	二代病例在末次接触无症状感染者后 14 天内发病；
en-us	the onset of the second-generation case happened within 14 days after the last contact with the asymptomatic infected person;

zh-cn	二代病例除与首例接触外，无其他相关暴露史或接触史。
en-us	the second-generation case had no other relevant exposure history or contact history than with the asymptomatic infected person.

zh-cn	建议调查时，应尽早采样，若无症状感染者阳性标本的 采样时间早于二代病例的发病时间，则证据更强。
en-us	It is recommended that sampling be done as early as possible during investigation. If sampling in the case of positive specimens of the asymptomatic infected person was earlier than the onset of the second-generation case, the evidence is considered to be stronger.

zh-cn	此外，还 建议采集调查当日及 3 至 4 周后的血清标本留存备查。
en-us	In addition, it is recommended to collect serum specimens on the day of investigation and again 3-4 weeks later for future reference.

zh-cn	传播途径分析。
en-us	Analysis of transmission routes.

zh-cn	在现场调查中，应注意收集病例间的接触方式、距离及 时间，接触时个人防护和手卫生等相关情况，
en-us	During field investigations, make sure the following information is collected: type of contact, contact distance, length of contact time, personal protection during contact, hand hygiene and other relevant conditions.

zh-cn	调查暴露场所的面积、人员密度、通风及空调使用情况，综合分析可能的 传播途径。
en-us	Investigate the floor area of the exposure site, density of people, and the ventilation and air conditioning used to comprehensively analyze possible routes of transmission.

zh-cn	发生在飞机、高铁车厢、网吧、歌厅等密闭空间的聚集 性疫情，分析发病与首例病例座位距离、近距离交谈时间， 厕所暴露、手卫生及个人防护等相关因素的关联性。
en-us	For a cluster of cases related to a closed space such as an airplane, a carriage in a high-speed train, an Internet bar, or a karaoke bar, analyze the correlation between development of illnesses of individuals and the index case in terms of seat distance, duration of short-distance conversation, toilet exposure, hand hygiene, and personal protection.

zh-cn	如飞沫传播和接触传播无法解释病例的时间和空间分布，怀疑气溶胶传播的可能时，建议尽可能采集机舱、高铁车厢及厕所等相关场所的空气样品、环境涂抹拭子等，检测病毒含量和活性。
en-us	If the time and spatial distribution of cases cannot be explained by droplet transmission or contact transmission and the possibility of aerosol transmission is suspected, it is recommended to collect air samples and environmental smears and swabs from the cabin, high-speed train carriage, toilet, or other relevant places to test the virus content and activity.

zh-cn	介绍事件的发现和报告过程；当地疫情概况，包括发病 数、死亡数和病死率等。
en-us	Describe the process of event detection and the general situation of the local outbreak including the number of cases, deaths, and case fatality rate.

zh-cn	流行病学调查。
en-us	Epidemiological investigation

zh-cn	描述事件病例总数和分类（包括确诊病例、疑似病例 和无症状感染者）、重症及死亡情况。
en-us	Describe the total number  and  classification of  cases (including confirmed cases, suspected cases and asymptomatic  infected persons), severe cases, and deaths.

zh-cn	按发病日期逐一描述每例病例的基本情况（姓名、年 龄、性别、职业、发病时的居住地址、身份证号码）、发病 和诊疗经过、临床表现、标本采集和检测情况、病情进展及 转归情况、暴露史、密切接触者、发病后活动轨迹、个人防 护措施情况等。
en-us	Describe each case by onset date including the basic information (name, age, gender, occupation, residential address at  the  time of onset, and  ID  number); progression of symptoms, diagnosis, and  treatment; clinical manifestations; specimen collection and  testing; progression and  outcome of disease; exposure history; close contacts; tracking of activities after onset; and personal protective measures.

zh-cn	根据病例调查结果，绘制流行曲线、时序图、病例关 系图，梳理总结聚集性疫情调查的关键信息填写附件 2。
en-us	According to  the  case investigation results, draw the  epidemic curve, time  sequence diagram, and  case relationship diagram, then organize and summarize the key information of the cluster investigation and complete the form shown in Table S1.

zh-cn	病例暴露场所调查。
en-us	Investigation of place of exposure

zh-cn	描述暴露场所的环境、共同暴露人数、人员接触和防护 情况。
en-us	Describe the environment of the exposure place, the number of people with a common exposure, personal contact and protection measures.

zh-cn	必要时，可绘制暴露场所平面图。
en-us	If necessary, draw a diagram of the exposed area.

zh-cn	密切接触者调查。
en-us	Investigation of close contacts

zh-cn	描述病例与其密切接触者的关系、接触方式和频率、最 早和最后接触时间，确定密切接触者总数、转归情况及人数。
en-us	Describe the relationship between the case and his/her close contacts, type and frequency of contact and the first and last contact time; determine the total number of close contacts, their outcomes, and the number of people involved.

zh-cn	采取的措施
en-us	Measures taken

zh-cn	描述针对此次聚集性疫情采取防控措施的种类、时间及落实情况。
en-us	Describe the type, time, and implementation of the prevention and control measures for the cluster.

zh-cn	调查结论
en-us	Investigation findings

zh-cn	判断疫情传播代际和传播链，明确传染来源和传播途 径。
en-us	Determine the generation of cases in the cluster, chains of transmission, and the source and route of transmission.

zh-cn	建议
en-us	Recommendations

zh-cn	基于此次聚集性疫情调查结果和发现的问题，提出针对 性防控建议。
en-us	On  the basis of the investigation findings and problems identified, propose targeted prevention and control recommendations.