Effects of a closed-loop system against SARS-CoV-2 at the Beijing 2022 Olympic Winter Games: a descriptive and modeling study.

BACKGROUND: To assess the efficacy of the epidemic prevention measures of the "closed-loop" system adopted by the Beijing 2022 Olympic Winter Games (BOWG). METHODS: We retrospectively collected and analyzed information, including age, sex, nationality, vaccination status, date of diagnosis, and date of entry, from 280 SARS-CoV-2-positive individuals identified during the BOWG. A susceptibility-exposed-infectious-remove model was employed to evaluate the effectiveness of epidemic prevention strategies on controlling the spread of SARS-CoV-2 under different scenarios during the BOWG. RESULTS: Regarding SARS-CoV-2-positive cases, 97.9% were imported, and 96.4% were asymptomatic. The median age was 37 years (range: 29-47 years), and 73.9% were male, with the majority of cases being broadcasters and European attendees. Regarding vaccination status, 93.5% were fully vaccinated, and six cases were considered to have been infected in the closed-loop system during the BOWG. Assuming that the BOWG adopted a semi-closed-loop management system, the cumulative number of confirmed cases would be 1,137 for quick quarantine measures (3 d later) implemented and 5,530 for delayed quarantine measures (9 d later) implemented. This modeling revealed that stringent pandemic prevention measures and closed-loop management effectively controlled the spread of SARS-CoV-2 during the BOWG. CONCLUSION: Imported cases are considered the main risk factor for SARS-CoV-2 transmission during mass gatherings, but a comprehensive closed-loop system could minimize transmission among attendees and general personnel.

National survey of do not attempt resuscitation decisions on out-of-hospital cardiac arrest in China.

BACKGROUND: To investigate and understand the determinants of decisions not to attempt resuscitation following out-of-hospital cardiac arrest, to contribute to establishing rules that are appropriate to China. METHODS: We recruited participants through directors of emergency medical services across China. A 28-question web survey was available between February 5 and March 6, 2021 that targeted demographic information and views on emergency work and cardiopulmonary resuscitation. Each question was assigned a value between 1 and 7 based on the level of importance from low to high. T-tests, one-way analysis of variance, and Kruskal-Wallis H-tests were used to compare continuous variables. Binary logistic regression analysis was used to identify factors influencing when people considered it suitable to initiate cardiopulmonary resuscitation. RESULTS: The study involved 4289 participants from 31 provinces, autonomous regions and municipalities in mainland China, of whom 52.8% were male. The top three reasons for not attempting cardiopulmonary resuscitation were decomposition/hypostasis/rigor mortis (6.39 ± 1.44 points), massive injury (4.57 ± 2.08 points) and family members' preference (4.35 ± 1.98 points). In total, 2761 (64.4%) thought emergency services should not attempt cardiopulmonary resuscitation when cardiac arrest had happened more than 30 min before, and there had been no bystander cardiopulmonary resuscitation. Gender (OR 1.233, p = 0.002), religion (OR 1.147, p = 0.046), level (OR 0.903, p = 0.028) or classification of city (OR 0.920, p = 0.049), years of work experience (OR 0.884, p = 0.004), and major (OR 1.032, p = 0.044) all influenced how long after cardiac arrest was considered suitable for initiating cardiopulmonary resuscitation. CONCLUSIONS: Chinese emergency physicians have different perceptions of when not to attempt resuscitation to those practicing elsewhere. The existing guidelines for resuscitation are not suitable for China, and China-specific guidelines need to be established.

Medical services for sports injuries and illnesses in the Beijing 2022 Olympic Winter Games.

BACKGROUND: Beijing 2022 Olympic Winter Games was the second Games held amid the COVID-19 pandemic. To a certain extent, it has altered the way sporting activities operate. There is a lack of knowledge on injury risk and illness occurrence in elite winter sport athletes amid the COVID-19 pandemic. This study aimed to describe the incidence of injuries and illnesses sustained during the XXIV Olympic Winter Games in Beijing from February 4 to 20, 2022. METHODS: We recorded the daily number of injuries and illnesses among athletes reported by Beijing 2022 medical staff in the polyclinic, medical venues, and ambulance. We calculated injury and illness incidence as the number of injuries or illnesses occurring during competition or training, respectively, with incidence presented as injuries/illnesses per 100 athlete-days. RESULTS: In total, 2,897 athletes from 91 nations experienced injury or illness. Beijing 2022 medical staff reported 326 injuries and 80 illnesses, equaling 11.3 injuries and 2.8 illnesses per 100 athletes over the 17-day period. Altogether, 11% of the athletes incurred at least one injury and nearly 3% incurred at least one illness. The number of injured athletes was highest in the skating sports (n=104), followed by alpine skiing (n=53), ice track (n=37), freestyle skiing (n=36), and ice hockey (n=35), and was the lowest in the Nordic skiing disciplines (n=20). Of the 326 injuries, 14 (4.3%) led to an estimated absence from training or competition of more than 1 week. A total of 52 injured athletes were transferred to hospitals for further care. The number of athletes with illness (n=80) was the highest for skating (n=33) and Nordic skiing (n=22). A total of 50 illnesses (62.5%) were admitted to the department of dentistry/ophthalmology/otolaryngology, and the most common cause of illness was other causes, including preexisting illness and medicine (n=52, 65%). CONCLUSION: Overall, 11% of athletes incurred at least one injury during the Games, which is similar to the findings during the Olympic Winter Games in 2014 and 2018. Regarding illness, 2% of athletes were affected, which is approximately one-third of the number affected in the 2018 Olympic Winter Games.

Medical services for sports injuries and illnesses in the Beijing 2022 Olympic Winter Games / 世界急诊医学杂志（英文）

BACKGROUND: Beijing 2022 Olympic Winter Games was the second Games held amid the COVID-19 pandemic. To a certain extent, it has altered the way sporting activities operate. There is a lack of knowledge on injury risk and illness occurrence in elite winter sport athletes amid the COVID-19 pandemic. This study aimed to describe the incidence of injuries and illnesses sustained during the XXIV Olympic Winter Games in Beijing from February 4 to 20, 2022. METHODS: We recorded the daily number of injuries and illnesses among athletes reported by Beijing 2022 medical staff in the polyclinic, medical venues, and ambulance. We calculated injury and illness incidence as the number of injuries or illnesses occurring during competition or training, respectively, with incidence presented as injuries/illnesses per 100 athlete-days. RESULTS: In total, 2,897 athletes from 91 nations experienced injury or illness. Beijing 2022 medical staff reported 326 injuries and 80 illnesses, equaling 11.3 injuries and 2.8 illnesses per 100 athletes over the 17-day period. Altogether, 11％ of the athletes incurred at least one injury and nearly 3％ incurred at least one illness. The number of injured athletes was highest in the skating sports (n=104), followed by alpine skiing (n=53), ice track (n=37), freestyle skiing (n=36), and ice hockey (n=35), and was the lowest in the Nordic skiing disciplines (n=20). Of the 326 injuries, 14 (4.3％) led to an estimated absence from training or competition of more than 1 week. A total of 52 injured athletes were transferred to hospitals for further care. The number of athletes with illness (n=80) was the highest for skating (n=33) and Nordic skiing (n=22). A total of 50 illnesses (62.5％) were admitted to the department of dentistry/ophthalmology/otolaryngology, and the most common cause of illness was other causes, including preexisting illness and medicine (n=52, 65％). CONCLUSION: Overall, 11％ of athletes incurred at least one injury during the Games, which is similar to the findings during the Olympic Winter Games in 2014 and 2018. Regarding illness, 2％ of athletes were affected, which is approximately one-third of the number affected in the 2018 Olympic Winter Games.

Transmission of SARS-CoV-2 during air travel: a descriptive and modelling study.

OBJECTIVES: To explore the potential of SARS-CoV-2 spread during air travel and the risk of in-flight transmission. METHODS: We enrolled all passengers and crew suspected of being infected with SARS-CoV-2, who bounded for Beijing on international flights. We specified the characteristics of all confirmed cases of COVID-19 infection and utilised Wells-Riley equation to estimate the infectivity of COVID-19 during air travel. RESULTS: We screened 4492 passengers and crew with suspected COVID-19 infection, verified 161 confirmed cases (mean age 28.6 years), and traced two confirmed cases who may have been infected in the aircraft. The estimated infectivity was 375 quanta/h (range 274-476), while the effective infectivity was only 4 quanta/h (range 2-5). The risk of per-person infection during a 13 h air travel in economy class was 0.56‰ (95% CI 0.41‰-0.72‰). CONCLUSION: We found that the universal use of face masks on the flight, together with the plane's ventilation system, significantly decreased the infectivity of COVID-19.KEY MESSAGESThe COVID-19 pandemic is changing the lifestyle in the world, especially air travel which has the potential to spread SARS-CoV-2.The universal use of face masks on the flight, together with the plane's ventilation system, significantly decreased the infectivity of COVID-19 on an aircraft.Our findings suggest that the risk of infection in aircraft was negligible.

Clinical characteristics of older patients infected with COVID-19: A descriptive study.

OBJECTIVES: Since the outbreak of 2019 novel coronavirus (COVID-19), which has spread in the world rapidly. Population have a susceptibility to COVID-19, older people were more susceptible to have a variety diseases than younger, including COVID-19 infection with no doubt. This study focused on older patients with COVID-19 infection and analyzed the epidemiological and clinical characteristics of them. METHODS: We collected information on confirmed older patient transferred by Beijing Emergency Medical Service (EMS) to the designated hospitals from Jan 20 to Feb 29, 2020. The information including demographic, epidemiological, clinical, classification of severity and outcomes. All cases were categorized into three groups and compared the difference between aged 50-64 years, 65-79 years and older than 80 years. RESULTS: 56.7 % of elderly confirmed patients were male, fever (78.3 %), cough (56.7 %), dyspnea (30.0 %), and fatigue (23.3 %) were common symptoms of COVID-19 infection. Classification of severity has statistically significant differences between the three groups, compared with middle-aged patients and aged 65-79 years group, older than 80 years group had significant statistical differences in contacted to symptomatic case in 14 days. As of Feb 29, 38.3 % patients had discharged and 53.3 % patients remained in hospital in our study, the fatality of COVID-19 infection in elderly was 8.3 %. CONCLUSIONS: The COVID-19 infection is generally susceptible with a relatively high fatality rate in older patients, we should pay more attention to the elderly patients with COVID-19 infection.

Characteristics of COVID-19 infection in Beijing.

BACKGROUND: Since the first case of a novel coronavirus (COVID-19) infection pneumonia was detected in Wuhan, China, a series of confirmed cases of the COVID-19 were found in Beijing. We analyzed the data of 262 confirmed cases to determine the clinical and epidemiological characteristics of COVID-19 in Beijing. METHODS: We collected patients who were transferred by Beijing Emergency Medical Service to the designated hospitals. The information on demographic, epidemiological, clinical, laboratory test for the COVID-19 virus, diagnostic classification, cluster case and outcome were obtained. Furthermore we compared the characteristics between severe and common confirmed cases which including mild cases, no-pneumonia cases and asymptomatic cases, and we also compared the features between COVID-19 and 2003 SARS. FINDINGS: By Feb 10, 2020, 262 patients were transferred from the hospitals across Beijing to the designated hospitals for special treatment of the COVID-19 infected by Beijing emergency medical service. Among of 262 patients, 46 (17.6%) were severe cases, 216 (82.4%) were common cases, which including 192 (73.3%) mild cases, 11(4.2%) non-pneumonia cases and 13 (5.0%) asymptomatic cases respectively. The median age of patients was 47.5 years old and 48.5% were male. 192 (73.3%) patients were residents of Beijing, 50 (26.0%) of which had been to Wuhan, 116 (60.4%) had close contact with confirmed cases, 21 (10.9%) had no contact history. The most common symptoms at the onset of illness were fever (82.1%), cough (45.8%), fatigue (26.3%), dyspnea (6.9%) and headache (6.5%). The median incubation period was 6.7 days, the interval time from between illness onset and seeing a doctor was 4.5 days. As of Feb 10, 17.2% patients have discharged and 81.7% patients remain in hospital in our study, the fatality of COVID-19 infection in Beijing was 0.9%. INTERPRETATION: On the basis of this study, we provided the ratio of the COVID-19 infection on the severe cases to the mild, asymptomatic and non-pneumonia cases in Beijing. Population was generally susceptible, and with a relatively low fatality rate. The measures to prevent transmission was very successful at early stage, the next steps on the COVID-19 infection should be focused on early isolation of patients and quarantine for close contacts in families and communities in Beijing. FUNDING: Beijing Municipal Science and Technology Commission and Ministry of Science and Technology.