“全球疫情会诊室”：中国是否出现了群体免疫现象？
6月12日，中央广播电视总台中国国际电视台（CGTN）的“全球疫情会诊室”节目邀请广东省的三位抗疫医生与来自墨西哥和阿根廷的医学专家，通过网络视频会议交流新冠肺炎防治经验。
从5月起，拉丁美洲成为全球新的疫情中心。根据美国约翰斯·霍普金斯大学的数据，截至目前，墨西哥新冠肺炎累计确诊病例13.9万例，死亡人数超过1.6万例；阿根廷确诊病例超过2.8万例，死亡785例。
据墨西哥和阿根廷的专家介绍，这两个国家目前疫情最严重的地方都是大城市，特别是有国际机场的城市或边境城市，而且目前还面临着医疗资源的短缺，这也导致了医护人员的感染率和重症病人的死亡率都很高。
In the latest episodes of CGTN's live stream program "COVID-19 Frontline" held on Friday, June 12, doctors from a Guangdong medical team that served in Wuhan shared their COVID-19 treatment experience with their counterparts from Latin American countries.
中国医生与墨西哥、阿根廷同行在节目中交流抗疫经验
大范围戴口罩能否起到防护作用？
墨西哥瓜纳华托大学教授、传染病专家亚历杭德罗·马西亚斯（Alejandro Macias）说，东西方国家对于戴口罩是否能有效预防新冠肺炎一直存在较大争议。他想知道中国民众是否在公共交通、公园、电影院等公共场所大范围戴口罩，戴口罩对阻止新冠病毒的传播起到什么作用。
南方医科大学南方医院呼吸与危重症医学科副主任医师胡国栋回答说，中国目前基本上还是全民戴口罩，从实际结果来看，戴口罩肯定是有帮助的，不仅可以预防新冠肺炎，还显著降低了其他呼吸道传染病的发病率。他介绍称，从他们医院今年上半年呼吸科门诊的接诊量来看，在病人和其他人都广泛戴口罩之后，包括流感、肺炎在内的呼吸道传染病都明显减少了。
广州医科大学附属第一医院心内科主任医师陈爱兰补充说，戴口罩对于保护易感人群、避免接触潜在的感染者是非常有帮助的，也是最简单易行又可靠的一种方法。让民众树立戴口罩的观念是基于对新冠肺炎传播机制的认识，对民众的宣传教育很重要。在中国，1月份的时候也有很多人反对戴口罩，尤其是年龄偏大的人。但是在疫情发展的过程中，政府、医护人员、社区工作人员等做了很多相关的知识宣传工作，让戴口罩进行自我保护的意识深入到每一个人心里。
Alejandro Macias, infectious disease specialist and former Mexico influenza commissioner, said it was a little hard to convince people to use masks, but the rate of using face-masks in Mexico is increasing little by little. He asked about the situation in China and whether everybody wears mask.
Hu Guodong, deputy chief physician of Respiratory and Critical Care Medicine, Nanfang Hospital in China, said everyone in China wears mask. Wearing masks not only can prevent the spread of COVID-19, but also other respiratory diseases such as influenza and pneumonia.
Chen Ailan, chief of Department of Cardiology, the First Affiliated Hospital of Guangzhou Medical University, said many people objected to wearing a mask in January, especially older people. But several campaigns were set up to help people learn the importance of wearing masks. It is still the easiest and most reliable way to avoid the potential infection.
CGTN主持人邹韵在“全球疫情会诊室”北京演播室
对危重症患者的治疗经验
墨西哥国立自治大学医学院公共卫生系主任马拉基亚·洛佩兹（Malaquias Lopez）希望中国医生介绍一下对新冠肺炎重症病人的治疗经验。
中山大学附属第一医院重症医学科主任医师吴健锋介绍说，首先是尽量防止病人从轻型、普通型转为重型和危重型，这就需要对病人的早期筛查、诊断和治疗。因为一旦病人转为重症和危重症，死亡率是很高的。他认为，一旦病人转为重症和危重症，治疗原则和治疗此前的急性呼吸窘迫综合征（Acute respiratory distress syndrome）没有本质区别，主要的治疗手段包括使用呼吸机、肺保护通气、俯卧位通气、必要的时候各项器官支持以及ECMO等。他说，武汉有专家最近发表的论文显示，ECMO治愈重症病人的比率高达50%，这也说明充分的医疗资源支持才能保证病人的存活率。
Malaquias Lopez, professor of Public Health at the Faculty of Medicine, National Autonomous University of Mexico, wanted to learn more about Chinese doctors' experience on treating critical COVID-19 patients.
Wu Jianfeng, chief of Critical Care Medicine, the First Affiliated Hospital of Sun Yat-sen University, said the first is to prevent patients from developing from mild to severe and critical, which requires early screening, diagnosis and treatment. Because once the patient becomes critically ill, the mortality rate is very high. In his opinion, there is no essential difference between the principles of COVID-19 treatment and the treatment of previous acute respiratory distress syndrome once a patient has become critically ill. The main treatments include prone ventilation, organ support and extra-corporeal membrane oxygenation (ECMO) when necessary. He said a recent paper published by experts in Wuhan showed that ECMO cured as many as 50 percent of critically ill patients, suggesting that adequate medical resources were needed to ensure survival rate.
中国是否出现了群体免疫现象？
在节目进行期间，一名巴西专家通过社交平台向中国同行提问：中国目前是否出现了群体免疫现象？
吴健锋回答说，目前为止，中国没有任何一个地方发现有群体免疫，包括武汉。武汉刚完成对一千万市民的全体核酸检测，结果显示只有300名无症状感染者，说明武汉整体新冠肺炎的感染率是非常低的。另外，医护人员作为感染风险很高的密切接触者，他们的抗体检测结果也显示没有群体免疫现象。比如广东驰援武汉的400多名医护人员，抗体检测结果都是阴性，也就是说没有一个人体内有新冠病毒抗体。所以，至少在中国，目前没有发现哪个地区的人有群体免疫现象。
Emilio Puschmann, healthcare and technology entrepreneur in Brazil, asked about whether China has herd immunity.
Wu Jianfeng, chief of Critical Care Medicine, the First Affiliated Hospital of Sun Yat-sen University, answered that no city in China including Wuhan showed that herd immunity happened. 11 million residents of Wuhan got tested for antibodies, but the result shows the low level of immunity. The lack of herd immunity means Chinese people are still at high risk and are vulnerable to another wave of coronavirus. As of now, only one city in Italy is near herd immunity after 50 percent of its residents tested positive for COVID-19 antibodies. But the result needs to be further confirmed.
复工复产时哪些人需要做核酸检测？
马西亚斯教授又问，中国在复工复产的过程中会对哪些人做核酸检测？
陈爱兰医生说，中国在复工复产时为了保障安全，主要是对一些接触人比较多的从业人员抽样做核酸检测，比如出租车司机。另外，通过大数据平台对人员行程的追踪，接触过高风险人群或者到过高风险区域的人需要做核酸检测。在学生复学的时候，行程追踪显示感染风险较高的学生及其家人都需要做核酸检测；在北上广这些大城市，所有的老师都做了核酸检测。
使用恢复期血浆疗法需要注意什么？
阿根廷萨尔塔天主教大学健康科学学院学术部长费尔南多·加洛（Fernando Gallo）想了解中国使用恢复期血浆疗法的临床经验。
陈医生介绍，在广州医科大学附属第一医院，钟南山院士团队使用过恢复期血浆对患者进行治疗，结果显示病人病毒转阴性的速度相对比较快，病情也出现好转，这说明恢复期血浆确实是有帮助的。不过，一般考虑使用血浆疗法的都是从重症向危重症发展的病人，这部分病人通常肺部的损伤特别严重，往往还合并了多个器官的损害，用恢复期血浆并不能起到完全治愈的作用。
吴医生补充说，现在研究的重点是把恢复期血浆中针对病毒的有效抗体找出来，而不是简单地把血浆输给病人，否则造成的风险是非常高的。因为病毒复制中有一个很大的潜在风险，就是有些抗体会让病毒的抗体依赖性增强，进而增强病毒的复制。因此他认为，在目前不知道哪个抗体对病毒有帮助、哪个抗体有害的情况下，对康复期血浆的使用要非常慎重。
Alejandro Macias also asked about how often do medical staff receive PCR test. Since medical staff contact a lot of patients and if they are asymptomatic, he or she can transmit the virus to a lot of people.
Wu Jianfeng said although the epidemic is well under control, the high level of protection is still necessary in the hospital. Doctors wear N95 masks and protective clothing to reduce the chances of being infected by asymptomatic persons. It also reduces the chance of infecting others.
Chen Ailan added that some taxi drivers, teachers have also received PCR test. In the process of resumption of work and production, everyone needs to get a temperature check in order to enter restaurants, hotels and commercial areas. Besides, COVID-19 contact tracing apps are used to track down people's contact history to avoid the spread of the virus.
在时长近一个半小时的节目中，中外专家还探讨了治愈病人的再感染几率，墨西哥和阿根廷目前的疫情、防护和治疗情况、医护人员的感染率等问题，中国医生们都结合自己的临床经验给出了回答和建议。
In later episodes of "COVID-19 Frontline," more frontline doctors and experts from Wuhan will join in to share their experience with their colleagues from other parts of the world.