In resource-limited areas, severe shortages of radiologist contribute to high rates of missed pulmonary tuberculosis (PTB) cases when relying solely on conventional chest X-ray (CXR). Although artificial intelligence (AI)-powered computer-aided detection (CAD) has shown effective in PTB diagnosis, its real-world clinical utility and scalability in primary healthcare settings remained underexplored. To evaluate the real-world performance of CAD technology for triaging of PTB patients in primary healthcare facilities in high-incidence areas, and to assess its potential for optimizing radiological resource allocation. We conducted a retrospective paired-design diagnostic accuracy study using CXR images collected from 7 county- and 32 township-level healthcare facilities in Yichang city between 2022 and 2024. All images were retrospectively reprocessed with CAD software (JF CXR-1 v2), and the original radiology reports interpreted by radiologists were extracted. CAD and radiologist performances were compared using two primary evaluation indicators: diagnostic yield among diagnosed cases (DYD) and positive predictive value (PPV). Subgroup analysis (by region, age, sex, healthcare facility tier, and patients category) and sensitivity analysis were conducted to assess the robustness of the results. Among 93,319 enrolled study patients (including 273 bacteriologically confirmed PTB cases), CAD demonstrated a substantially higher DYD (83.88%, 229/273) than radiologists (25.64%, 70/273), though with much lower PPV (1.70% vs. 10.31%). This high-sensitivity performance achieved an 85.52% reduction (only 13,515 instead of 93,319 CXRs) in radiologist workload via selective review of CAD-positive images, without missing any radiologist-identified PTB cases. Furthermore, among CAD-positive images, probability scores >0.75 was a key threshold for identifying high-risk PTB patients, prioritizing for radiologist review. Subgroup analysis further revealed that CAD outperformed radiologists in identifying PTB cases across all scenarios, despite some heterogeneity. In township healthcare facilities, CAD demonstrated significantly better performance than in county-level facilities, with DYD of 86.72% and 62.50%, and PPV of 2.00% and 0.65%, respectively. CAD technology demonstrates valuable PTB screening performance in primary healthcare facilities. Combined with a tiered "AI pre-screening with selective human review" strategy, this approach effectively alleviates workload of radiologist in resource-constrained regions, offering a scalable solution for tuberculosis prevention and control.

Early diagnosis of pulmonary tuberculosis (PTB) is essential for individual case treatment and community transmission control. However, the impact of the COVID-19 pandemic on PTB diagnosis remains inadequately understood. In this study, we aimed to investigate the diagnostic delay in patients with PTB before, during and after the COVID-19 pandemic. We conducted a longitudinal study of PTB in Yichang City from 2005 to 2023, utilizing data from the Tuberculosis Information Management System of China. The distribution of diagnostic delay (DD) was analyzed across three periods: pre-pandemic, during the pandemic, and post-pandemic. Multivariate mixed-effects logistic regression models were employed to identify factors associated with prolonged DD, defined as a delay exceeding 28 days. A total of 58,774 patients with PTB were included in this study. The average annual number of cases was 3,293 pre-pandemic, 2,319 during the pandemic, and 2,426 post-pandemic. The fitted median DD in the pre-pandemic period (31.7 days, interquartile range [IQR] = 13.8–72.8) was significantly longer than that in the pandemic period (23.8 days, IQR = 11.3–50.3) and the post-pandemic period (20.6 days, IQR = 9-47.1) (p < 0.01). Elder patients aged 65 years and older had a longer median DD (32 days, IQR = 14.2–72.0) than patients aged 18–64 years (median: 30.1 days, IQR = 13.1–68.9) and patients under 18 years (median: 19.5 days, IQR = 8.6–44.2) (p < 0.01). Patients residing in rural areas also had a longer median DD (31 days, IQR = 14.2–72.0) compared to those in urban (median: 29.4 days, IQR = 13.7–70.2) (p < 0.01). Older age (adjusted Odds Ratio [aOR] = 2.20, 95

BACKGROUND:The World Health Organization previously set goals of controlling morbidity due to schistosomiasis by 2020 and attaining elimination as a public health problem (EPHP) by 2025 (now adjusted to 2030 in the new neglected tropical diseases roadmap). As these milestones are reached, it is important that programs reassess their treatment strategies to either maintain these goals or progress from morbidity control to EPHP and ultimately to interruption of transmission. In this study, we consider different mass drug administration (MDA) strategies to maintain the goals.METHODS:We used 2 independently developed, individual-based stochastic models of schistosomiasis transmission to assess the optimal treatment strategy of a multiyear program to maintain the morbidity control and the EPHP goals.RESULTS:We found that, in moderate-prevalence settings, once the morbidity control and EPHP goals are reached it may be possible to maintain the goals using less frequent MDAs than those that are required to achieve the goals. On the other hand, in some high-transmission settings, if control efforts are reduced after achieving the goals, particularly the morbidity control goal, there is a high chance of recrudescence.CONCLUSIONS:To reduce the risk of recrudescence after the goals are achieved, programs have to re-evaluate their strategies and decide to either maintain these goals with reduced efforts where feasible or continue with at least the same efforts required to reach the goals.

Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q1, Q3) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8th -13th day after the entry.

Influenza endangers human health but can be prevented in part by vaccination. Assessing influenza vaccine effectiveness (VE) provides scientific evidence for developing influenza vaccination policy. We conducted a systematic review and meta-analysis of studies that evaluated influenza VE in mainland China. We searched six relevant databases as of 30 August 2019 to identify studies and used Review Manager 5.3 software to analyze the included studies. The Newcastle–Ottawa scale was used to assess the risk of publication bias. We identified 1408 publications, and after removing duplicates and screening full texts, we included 21 studies in the analyses. Studies were conducted in Beijing, Guangzhou, Suzhou, and Zhejiang province from the 2010/11 influenza season through the 2017/18 influenza season. Overall influenza VE for laboratory confirmed influenza was 36% (95% CI: 25–46%). In the subgroup analysis, VE was 45% (95% CI: 18–64%) for children 6–35 months who received one dose of influenza vaccine, and 57% (95% CI: 50–64%) who received two doses. VE was 47% (95% CI: 39–54%) for children 6 months to 8 years, and 18% (95% CI: 0–33%) for adults ≥60 years. For inpatients, VE was 21% (95% CI: −11–44%). We conclude that influenza vaccines that were used in mainland China had a moderate effectiveness, with VE being higher among children than the elderly. Influenza VE should be continuously monitored in mainland China to provide evidence for policy making and improving uptake of the influenza vaccine.

BACKGROUND:The relative contributions of asymptomatic, presymptomatic, and symptomatic transmission of severe acute respiratory syndrome coronavirus 2 have not been clearly measured, although control measures may differ in response to the risk of spread posed by different types of cases. METHODS:We collected detailed information on transmission events and symptom status based on laboratory-confirmed patient data and contact tracing data from 4 provinces and 1 municipality in China. We estimated the variation in risk of transmission over time and the severity of secondary infections by symptomatic status of the infector. RESULTS:There were 393 symptomatic index cases with 3136 close contacts and 185 asymptomatic index cases with 1078 close contacts included in the study. The secondary attack rates among close contacts of symptomatic and asymptomatic index cases were 4.1% (128 of 3136) and 1.1% (12 of 1078), respectively, corresponding to a higher transmission risk from symptomatic cases than from asymptomatic cases (odds ratio, 3.79; 95% confidence interval, 2.06-6.95). Approximately 25% (32 of 128) and 50% (6 of 12) of the infected close contacts were asymptomatic from symptomatic and asymptomatic index cases, respectively, while more than one third (38%) of the infections in the close contacts of symptomatic cases were attributable to exposure to the index cases before symptom onset. CONCLUSIONS:Asymptomatic and presymptomatic transmissions play an important role in spreading infection, although asymptomatic cases pose a lower risk of transmission than symptomatic cases. Early case detection and effective test-and-trace measures are important to reduce transmission.

COVID-19 is an emerging infectious disease caused by SARS-CoV-2. After the infection of the virus, the host immune system is stimulated to produce multifarious specific antibodies to decrease or eliminate effects of the pathogen. Study of the specific antibodies dynamic characteristics in patients with COVID-19 is very important for the understanding and diagnosis of the disease, research and development of vaccine, and planning of prevention and control strategy. This paper reviews and summarizes the domestic and oversea research on dynamic characteristics of specific antibodies of COVID-19 patients, including the antibody producing, duration and level, and its possible influencing factors in order to improve the understanding of the immunological characteristics of COVID-19.

目的 通过开展线上问卷调查,了解公众对新型冠状病毒肺炎重要防控知识的知晓情况,以更好地开展后续宣传教育工作.方法 使用问卷星生成问卷,并通过中国疾病预防控制中心官方微信公众号发布,应用SPSS 18.0软件进行数据分析.采用x2检验或Fisher确切概率法进行分类资料样本间率的比较,采用logistic多因素进行二元回归分析.结果 本次网络调查共收集有效应答问卷7011份,大众对新冠肺炎两个主要传播途径(呼吸道飞沫传播和接触传播)的认知率分别为99.7％和97.5％.不同年龄、职业在新冠肺炎基本特征、疾病严重程度的认知存在显著性差异.农民、务工人员和学生对传播途径和疾病主要特征的正确认知率均较低,18～29岁人群对"儿童症状较轻"的认知率最低(62.7％).73.3％的调查对象认为新冠肺炎"较重"或"很重",年轻、文化水平较高人群及医务人员中,认为新冠肺炎严重的比例低于年老或受教育程度低者.结论 大众普遍正确掌握新冠肺炎主要传播途径;不同年龄、职业的社会大众对新冠肺炎防控知识的认知存在显著性差异,这种差异会影响对新冠肺炎严重程度的判断.本次针对新冠肺炎的主动宣教效果显著,但除重视传统传播渠道外,应结合新媒体、标语等多种途径,对不同社交活跃程度的人群开展针对性宣传,以提高宣传效果,落实精准防控.

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.

季节性流感（简称流感）是由季节性流感病毒引起的急性呼吸道传染病，流感病毒传播迅速，各年龄段人群均易感染，每年可引起季节性流行。流感的临床特征对于疾病的诊断和治疗具有重要意义，而儿童、成人和老年人群感染流感病毒后出现的临床特征存在差异，疾病严重程度也有所不同。本文通过对国内外不同年龄人群感染流感病毒后的临床特征和病情严重程度等研究进行归纳分析，以期对流感的及时识别、诊断和治疗提供证据支持。

Abstract Background The relative contributions of asymptomatic, pre-symptomatic and symptomatic transmission of SARS-CoV-2 have not been clearly measured although control measures may differ in response to the risk of spread posed by different types of cases. Methods We collected detailed information on transmission events and symptom status based on laboratory-confirmed patient data and contact tracing data from four provinces and one municipality in China. We estimated the variation in risk of transmission over time, and the severity of secondary infections, by symptomatic status of the infector. Results There were 393 symptomatic index cases with 3136 close contacts and 185 asymptomatic index cases with 1078 close contacts included into the study. The secondary attack rate among close contacts of symptomatic and asymptomatic index cases were 4.1% (128/3136) and 1.1% (12/1078), respectively, corresponding to a higher transmission risk from symptomatic cases than from asymptomatic cases (OR: 3.79, 95% CI: 2.06, 6.95). Approximately 25% (32/128) and 50% (6/12) of the infected close contacts were asymptomatic from symptomatic and asymptomatic index cases, respectively, while more than one third (38%) of the infections in the close contacts of symptomatic cases were attributable to exposure to the index cases before symptom onset. Infected contacts of asymptomatic index cases were more likely to be asymptomatic and less likely to be severe. Conclusions Asymptomatic and pre-symptomatic transmission play an important role in spreading infection, although asymptomatic cases pose a lower risk of transmission than symptomatic cases. Early case detection and effective test-and-trace measures are important to reduce transmission.

We estimated the symptomatic, PCR-confirmed secondary attack rate (SAR) for 2,382 close contacts of 476 symptomatic persons with coronavirus disease in Yichang, Hubei Province, China, identified during January 23–February 25, 2020. The SAR among all close contacts was 6.5%; among close contacts who lived with an index case-patient, the SAR was 10.8%; among close-contact spouses of index case-patients, the SAR was 15.9%. The SAR varied by close contact age, from 3.0% for those <18 years of age to 12.5% for those >60 years of age. Multilevel logistic regression showed that factors significantly associated with increased SAR were living together, being a spouse, and being >60 years of age. Multilevel regression did not support SAR differing significantly by whether the most recent contact occurred before or after the index case-patient’s onset of illness (p = 0.66). The relatively high SAR for coronavirus disease suggests relatively high virus transmissibility.

目的了解公众流感疫苗认知、接种现状及影响因素,为提高流感疫苗接种率提供科学依据。方法 2020年1月15日—4月30日期间,使用12320公益电话平台,对广州、廊坊、南京、苏州、太原和重庆等6地区公众流感疫苗认知和2019—2020年流感季流感疫苗接种现状开展电话调查,采用多因素logistic回归模型分析影响不同年龄段公众流感疫苗接种率的相关因素。结果有效应答共计12 263人。2019—2020年流感季,16.34%（1 959/11 989）受访者曾咨询过流感疫苗接种事宜,流感疫苗接种比例为12.95%（1 529/11 810）,其中6月龄～5岁儿童接种比例为26.84%（877/3 267）,6～17岁学生为14.78%（245/1 658）,18～59岁成年人为3.99%（199/4 989）,≥60岁老年人为10.97%（208/1 896）。仅5.22%（202/3 866）受访者认为流感疫苗不安全,74.85%（3 785/5 057）认为流感疫苗具有中等和较好的保护效果。多因素logistic回归分析显示,免费接种、咨询流感疫苗接种、认为流感疫苗保护效果好、接种方便可促进流感疫苗的接种。结论公众对流感疫苗安全性和保护效果认可度较高,作为流感重症高危人群的5岁以下儿童和老年人需要进一步提升流感疫苗接种覆盖率。加大对流感疫苗相关知识宣传力度,提供便捷的咨询和接种服务可提高公众流感疫苗接种率。

目的 了解新型冠状病毒肺炎疫情发生前、后公众的洗手相关行为及影响因素.方法 通过中国疾病预防控制中心官方微信公众号平台发放电子调查问卷.结果 调查期间后台访问13193次,共收集有效问卷7011份.日常生活每天洗手＞10次的比例从疫情前15.0％提升到疫情后48.3％,洗手次数小于3次的比例从疫情前13.3％下降到疫情后1.5％.每次洗手时间大于20 s的比例疫情前22.2％提升到疫情后51.7％,每次洗手小于10 s的比例疫情前35.3％下降到疫情后4.0％.手消毒液的使用率从疫情前40.6％增至疫情后84.0％.多因素logistic分析结果显示,疫情发生后男性、学生、初中及以下文化程度更有可能在日常生活中洗手次数＜3次/d.结论 新型冠状病毒肺炎疫情后公众对勤洗手预防病毒感染的接受程度高,需要针对性提升男性、学生和初中以下文化程度人群的手卫生教育,认识到洗手的重要性.

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.

Lei Zhou; Kai Nie; Hongting Zhao; Xiang Zhao; Bixiong Ye; Ji Wang; Cao Chen; Hong Wang; Jiangli Di; Jinsong Li; Chao Li; Zhixiao Chen; Ruiqi Ren; Peihua Niu; Hui Chen; Tao Chen; Yali Wang; Lili Li; Bingxue Han; Ruhan A; Si Chen; Dan Li; Dan Li; Chunxia Jin; Xin Zhang; Jiangmei Liu; Chunyu Xu; Yecheng Yao; Yenan Feng; Zhili Li; Bike Zhang; Yang Song; Peter Hao; Yanping Zhang; Hao Li; Qun Li; George F. Gao; Guoqing Shi; Wenbo Xu

As the progress of population aging in China, the proportion of elderly population is increasing. Both chronic diseases and infectious diseases can threaten the health of the elderly. There are many kinds of infectious diseases, including vaccine preventable infectious diseases affecting the health of adults, such as influenza, pneumococcal diseases and herpes zoster. In addition, the newly emerged COVID-19 has caused a pandemic in the world, resulting the highest proportion of deaths occurred in the elderly and posing a serious threat to the health of the elderly. This paper mainly summarizes the prevention and control of vaccine preventable diseases and COVID-19 to which the elderly are susceptible, analyzes the infectious disease problems affecting the health of elderly population, and recommends countermeasures for the prevention and control of these diseases in elderly population.

BACKGROUND:Between mid-January and early February, provinces of mainland China outside the epicentre in Hubei province were on high alert for importations and transmission of COVID-19. Many properties of COVID-19 infection and transmission were still not yet established. METHODS:We collated and analysed data on 449 of the earliest COVID-19 cases detected outside Hubei province to make inferences about transmission dynamics and severity of infection. We analysed 64 clusters to make inferences on serial interval and potential role of pre-symptomatic transmission. RESULTS:We estimated an epidemic doubling time of 5.3 days (95% confidence interval (CI): 4.3, 6.7) and a median incubation period of 4.6 days (95% CI: 4.0, 5.2). We estimated a serial interval distribution with mean 5.7 days (95% CI: 4.7, 6.8) and standard deviation 3.5 days, and effective reproductive number was 1.98 (95% CI: 1.68, 2.35). We estimated that 32/80 (40%) of transmission events were likely to have occurred prior to symptoms onset in primary cases. Secondary cases in clusters had less severe illness on average than cluster primary cases. CONCLUSIONS:The majority of transmissions are occurring around illness onset in an infected person, and pre-symptomatic transmission does play a role. Detection of milder infections among the secondary cases may be more reflective of true disease severity.

An online survey conducted March 18-19, 2020 on the official China CDC WeChat account platform was used to evaluate the effect of public education about masks usage during the new coronavirus disease 2019 (COVID-19) epidemic. Chinese nationals older than 18 were eligible for the survey. The survey collected 5,761 questionnaires from the 31 provinces, municipalities, and autonomous regions of mainland China. 99.7% and 97.2% of the respondents answered correctly that respiratory droplets and direct contact were the main transmission routes. 73.3% of the respondents considered COVID-19 to be 'serious' or 'very serious'. When going to the hospital, 96.9% (2,885/2,976 had gone to a hospital) used a mask during the COVID-19 epidemic, while 41.1% (2,367/5,761) did not use a mask before the epidemic. Among the respondents that used public transportation and went shopping, 99.6% and 99.4%, respectively, wore masks. Among respondents who returned to work, 75.5% wore a mask at the workplace, while 86.3% of those who have not returned to work will choose to use masks when they return to the workplace. The Chinese public is highly likely to use a mask during COVID-19 epidemic, and the mask usage changed greatly since the COVID-19 outbreak. Therefore, public education has played an important role during the COVID-19 epidemic.