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1.
Proc Natl Acad Sci U S A ; 120(42): e2306710120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37824525

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic and the measures taken by authorities to control its spread have altered human behavior and mobility patterns in an unprecedented way. However, it remains unclear whether the population response to a COVID-19 outbreak varies within a city or among demographic groups. Here, we utilized passively recorded cellular signaling data at a spatial resolution of 1 km × 1 km for over 5 million users and epidemiological surveillance data collected during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2 outbreak from February to June 2022 in Shanghai, China, to investigate the heterogeneous response of different segments of the population at the within-city level and examine its relationship with the actual risk of infection. Changes in behavior were spatially heterogenous within the city and population groups and associated with both the infection incidence and adopted interventions. We also found that males and individuals aged 30 to 59 y old traveled more frequently, traveled longer distances, and their communities were more connected; the same groups were also associated with the highest SARS-CoV-2 incidence. Our results highlight the heterogeneous behavioral change of the Shanghai population to the SARS-CoV-2 Omicron BA.2 outbreak and the effect of heterogenous behavior on the spread of COVID-19, both spatially and demographically. These findings could be instrumental for the design of targeted interventions for the control and mitigation of future outbreaks of COVID-19, and, more broadly, of respiratory pathogens.


Assuntos
COVID-19 , Masculino , Humanos , COVID-19/epidemiologia , China/epidemiologia , SARS-CoV-2 , Surtos de Doenças , Processos Grupais
2.
BMC Med ; 21(1): 374, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37775772

RESUMO

BACKGROUND: After the first COVID-19 wave caused by the ancestral lineage, the pandemic has been fueled from the continuous emergence of new SARS-CoV-2 variants. Understanding key time-to-event periods for each emerging variant of concern is critical as it can provide insights into the future trajectory of the virus and help inform outbreak preparedness and response planning. Here, we aim to examine how the incubation period, serial interval, and generation time have changed from the ancestral SARS-CoV-2 lineage to different variants of concern. METHODS: We conducted a systematic review and meta-analysis that synthesized the estimates of incubation period, serial interval, and generation time (both realized and intrinsic) for the ancestral lineage, Alpha, Beta, and Omicron variants of SARS-CoV-2. RESULTS: Our study included 280 records obtained from 147 household studies, contact tracing studies, or studies where epidemiological links were known. With each emerging variant, we found a progressive shortening of each of the analyzed key time-to-event periods, although we did not find statistically significant differences between the Omicron subvariants. We found that Omicron BA.1 had the shortest pooled estimates for the incubation period (3.49 days, 95% CI: 3.13-4.86 days), Omicron BA.5 for the serial interval (2.37 days, 95% CI: 1.71-3.04 days), and Omicron BA.1 for the realized generation time (2.99 days, 95% CI: 2.48-3.49 days). Only one estimate for the intrinsic generation time was available for Omicron subvariants: 6.84 days (95% CrI: 5.72-8.60 days) for Omicron BA.1. The ancestral lineage had the highest pooled estimates for each investigated key time-to-event period. We also observed shorter pooled estimates for the serial interval compared to the incubation period across the virus lineages. When pooling the estimates across different virus lineages, we found considerable heterogeneities (I2 > 80%; I2 refers to the percentage of total variation across studies that is due to heterogeneity rather than chance), possibly resulting from heterogeneities between the different study populations (e.g., deployed interventions, social behavior, demographic characteristics). CONCLUSIONS: Our study supports the importance of conducting contact tracing and epidemiological investigations to monitor changes in SARS-CoV-2 transmission patterns. Our findings highlight a progressive shortening of the incubation period, serial interval, and generation time, which can lead to epidemics that spread faster, with larger peak incidence, and harder to control. We also consistently found a shorter serial interval than incubation period, suggesting that a key feature of SARS-CoV-2 is the potential for pre-symptomatic transmission. These observations are instrumental to plan for future COVID-19 waves.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Período de Incubação de Doenças Infecciosas , Pandemias
3.
Front Immunol ; 14: 1182751, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37359533

RESUMO

Background: Programmed death receptor 1 (PD-1) inhibition has shown durable response and mild adverse events (AEs) in adult malignancies. However, data on the clinical activity of PD-1 inhibition in pediatric patients are lacking. We comprehensively assessed the efficacy and safety of PD-1 inhibitor-based regimens for pediatric malignancies. Methods: We conducted a real-world, multi-institutional, retrospective analysis of pediatric malignancies treated with PD-1 inhibitor-based regimens. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS). The secondary endpoints included disease control rate (DCR), duration of response (DOR), and AEs. The Kaplan-Meier method was used to calculate PFS and DOR. The National Cancer Institute Common Toxicity Criteria for AEs (version 5.0) were used to grade toxicity. Results: A total of 93 and 109 patients were evaluated for efficacy and safety, respectively. For all efficacy-evaluable patients, PD-1 inhibitor monotherapy, combined chemotherapy, combined histone deacetylase inhibitor, and combined vascular endothelial growth factor receptor tyrosine kinase inhibitor cohorts, the ORR and DCR were 53.76%/81.72%, 56.67%/83.33%, 54.00%/80.00%, 100.00%/100.00%, and 12.50%/75.00%, respectively; the median PFS and DOR were 17.6/31.2 months, not achieved/not achieved, 14.9/31.2 months, 17.6/14.9 months, and 3.7/1.8 months, respectively; the incidence rate of AEs were 83.49%, 55.26%, 100.00%, 80.00%, and 100.00%, respectively. One patient in the PD-1 inhibitor-combined chemotherapy cohort discontinued treatment due to diabetic ketoacidosis. Conclusions: This largest retrospective analysis demonstrate that PD-1 inhibitor-based regimens are potentially effective and tolerable in pediatric malignancies. Our findings provide references for future clinical trials and practice of PD-1 inhibitors in pediatric cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Humanos , Criança , Estudos Retrospectivos , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1 , Fator A de Crescimento do Endotélio Vascular , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Apoptose
4.
Cancer Med ; 12(13): 14130-14137, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37183837

RESUMO

BACKGROUND: Pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) can be used in pediatric patients. This study assessed the safety and efficacy of PEG-rhG-CSF as a primary prophylactic drug against neutropenia after chemotherapy in pediatric patients with solid tumors or non-Hodgkin lymphoma (NHL). PATIENTS AND METHODS: This phase II study (between October 2020 and March 2022) enrolled pediatric patients with solid tumors or NHL treated with high-intensity chemotherapy and with grade ≥3 myelosuppression for at least 14 days during chemotherapy. Prophylactic PEG-rhG-CSF was given at 100 µg/kg body weight (maximum total dosage of 6 mg) once 24-48 h following chemotherapy for two cycles. The primary endpoint was the incidence of PEG-rhG-CSF-related adverse events (AEs). The key secondary endpoints were the rates of grade 3/4 neutropenia and febrile neutropenia (FN). RESULTS: This study included 160 pediatric patients with a median age of 6.22 (0.29, 18.00) years. Fifty-eight patients (36.25%) were diagnosed with sarcoma. AEs potentially related to PEG-rhG-CSF included bone pain (n = 32), fatigue (n = 21), pain at the injection site (n = 21), and myalgia (n = 20). The rates of grade 3/4 neutropenia and FN during treatment were 57.28% and 29.45%, respectively. CONCLUSION: PEG-rhG-CSF is well tolerated and effective in pediatric patients with solid tumors or NHL. These findings should be substantiated with further trials. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04547829.


Assuntos
Neoplasias Pulmonares , Linfoma não Hodgkin , Neutropenia , Humanos , Criança , Neoplasias Pulmonares/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/etiologia , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/efeitos adversos , Neutropenia/induzido quimicamente , Neutropenia/prevenção & controle , Neutropenia/tratamento farmacológico , Dor/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
5.
China CDC Wkly ; 5(5): 108-112, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-37006709

RESUMO

What is already known about this topic?: China has repeatedly contained multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks through a comprehensive set of targeted non-pharmaceutical interventions (NPIs). However, the effectiveness of such NPIs has not been systematically assessed. What is added by this report?: A multilayer deployment of case isolation, contact tracing, targeted community lockdowns, and mobility restrictions could potentially contain outbreaks caused by the SARS-CoV-2 ancestral strain, without the requirement of city-wide lockdowns. Mass testing could further aid in the efficacy and speed of containment. What are the implications for public health practice?: Pursuing containment in a timely fashion at the beginning of the pandemic, before the virus had the opportunity to spread and undergo extensive adaptive evolution, could help in averting an overall pandemic disease burden and be socioeconomically cost-effective.

6.
Polymers (Basel) ; 15(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36904424

RESUMO

Preparing flame-retardant polyamide 66 (PA66) fibers through melt spinning remains one of the biggest challenges nowadays. In this work, dipentaerythritol (Di-PE), an eco-friendly flame retardant, was blended into PA66 to prepare PA66/Di-PE composites and fibers. It was confirmed that Di-PE could significantly improve the flame-retardant properties of PA66 by blocking the terminal carboxyl groups, which was conducive to the formation of a continuous and compact char layer and the reduced production of combustible gas. The combustion results of the composites showed that the limiting oxygen index (LOI) increased from 23.5% to 29.4%, and underwriter laboratories 94 (UL-94) passed the V-0 grade. The peak of heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) decreased by 47.3%, 47.8%, and 44.8%, respectively, for the PA66/6 wt% Di-PE composite compared to those recorded for pure PA66. More importantly, the PA66/Di-PE composites possessed excellent spinnability. The prepared fibers still had good mechanical properties (tensile strength: 5.7 ± 0.2 cN/dtex), while maintaining good flame-retardant properties (LOI: 28.6%). This study provides an outstanding industrial production strategy for fabricating flame-retardant PA66 plastics and fibers.

7.
China CDC Wkly ; 5(3): 56-62, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36776461

RESUMO

What is already known about this topic?: Little is known about the epidemiology, natural history, and transmission patterns of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant. Monitoring the evolution of viral fitness of SARS-CoV-2 in the host population is key for preparedness and response planning. What is added by this report?: We analyzed a successfully contained local outbreak of Delta that took place in Hunan, China, and provided estimates of time-to-key event periods, infectiousness over time, and risk factors for SARS-CoV-2 infection and transmission for a still poorly understood variant. What are the implications for public health practice?: Our findings simultaneously shed light on both the characteristics of the Delta variant, by identifying key age groups, risk factors, and transmission pathways, and planning a future response effort against SARS-CoV-2.

8.
Emerg Microbes Infect ; 12(1): e2169197, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36644859

RESUMO

Omicron and its sublineages are currently predominant and have triggered epidemiological waves of SARS-CoV-2 around the world due to their high transmissibility and strong immune escape ability. Vaccines are key measures to control the COVID-19 burden. Omicron BA.2 caused a large-scale outbreak in Shanghai since March 2022 and resulted in over 0.6 million laboratory-confirmed infections. The vaccine coverage of primary immunization among residents aged 3 years and older in Shanghai exceeded 90%, and inactivated COVID-19 vaccines were mainly delivered. In the context of high vaccine coverage, we conducted a cohort study to assess vaccine effects on reducing the probability of developing symptoms or severity of disease in infections or nonsevere cases. A total of 48,243 eligible participants were included in this study, the majority of whom had asymptomatic infections (31.0%) and mild-to-moderate illness (67.9%). Domestically developed COVID-19 vaccines provide limited protection to prevent asymptomatic infection from developing into mild-to-moderate illness and durable protection to prevent nonsevere illness from progressing to severe illness caused by Omicron BA.2. Partial vaccination fails to provide effective protection in any situation. The level of vaccine effects on disease progression in the elderly over 80 years old was relatively lower compared with other age groups. Our study results added robust evidence for the vaccine performance against Omicron infection and could improve vaccine confidence.


Assuntos
COVID-19 , Infecção Laboratorial , Idoso , Humanos , Idoso de 80 Anos ou mais , Vacinas contra COVID-19 , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , China/epidemiologia , Vacinação , Infecções Assintomáticas , Surtos de Doenças/prevenção & controle
9.
BMC Pregnancy Childbirth ; 22(1): 960, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550461

RESUMO

BACKGROUND: Although pregnancy and childbirth comprise a life-course that most midwives experience, whether their own experiences of childbirth resonate with other women during childbirth remains to be determined. In this study, we therefore characterized midwives' empathic capabilities and defined their underlying factors. METHOD: We conducted a cross-sectional study with data from 464 midwives in Guangdong, China, that were collected through the "Chinese version of the Jefferson Scale of Empathy for Health Professionals (JSE-HP)." This questionnaire contains sections related to midwife demographics and delivery characteristics. We then implemented multivariate logistic regression analysis to identify empathy-related factors. RESULTS: Our analysis revealed 303 (65.3%) participants in the high-empathy group while 161 (34.7%) were in the middle-empathy group. Compared with the reference groups, these results indicated that higher empathy was associated with an elevated educational level (OR, 1.83; 95% CI, 1.04-3.25), high monthly salary (OR, 2.30; 95% CI, 1.11-4.80), and no shift work (OR, 2.89; 95% CI, 1.09-7.63). The odds of a high empathy score were higher for midwives who experienced two childbirths (2.27, 1.11-4.66) and for those who had children under the age of 3 years (2.81, 1.34-5.92). CONCLUSION: Midwives possess a moderate-to-high level of empathy, and the greater the number of childbirths they experienced and the younger their children, the higher their reported empathy score. This study contributes novel information regarding the empathic behavior of midwives toward women who give birth in China.


Assuntos
Tocologia , Gravidez , Criança , Feminino , Humanos , Pré-Escolar , Tocologia/métodos , Estudos Transversais , Empatia , Parto , Atitude do Pessoal de Saúde
10.
BMC Med ; 20(1): 442, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380354

RESUMO

BACKGROUND: The SARS-CoV-2 containment strategy has been successful in mainland China prior to the emergence of Omicron. However, in the era of highly transmissible variants, whether it is possible for China to sustain a local containment policy and under what conditions China could transition away from it are of paramount importance at the current stage of the pandemic. METHODS: We developed a spatially structured, fully stochastic, individual-based SARS-CoV-2 transmission model to evaluate the feasibility of sustaining SARS-CoV-2 local containment in mainland China considering the Omicron variants, China's current immunization level, and nonpharmaceutical interventions (NPIs). We also built a statistical model to estimate the overall disease burden under various hypothetical mitigation scenarios. RESULTS: We found that due to high transmissibility, neither Omicron BA.1 nor BA.2 could be contained by China's pre-Omicron NPI strategies which were successful prior to the emergence of the Omicron variants. However, increased intervention intensity, such as enhanced population mobility restrictions and multi-round mass testing, could lead to containment success. We estimated that an acute Omicron epidemic wave in mainland China would result in significant number of deaths if China were to reopen under current vaccine coverage with no antiviral uptake, while increasing vaccination coverage and antiviral uptake could substantially reduce the disease burden. CONCLUSIONS: As China's current vaccination has yet to reach high coverage in older populations, NPIs remain essential tools to maintain low levels of infection while building up protective population immunity, ensuring a smooth transition out of the pandemic phase while minimizing the overall disease burden.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Idoso , SARS-CoV-2/genética , Estudos de Viabilidade , COVID-19/epidemiologia , COVID-19/prevenção & controle , China/epidemiologia
11.
medRxiv ; 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36263065

RESUMO

Prior to the emergence of the Omicron variant, many cities in China had been able to maintain a "Zero-COVID" policy. They were able to achieve this without blanket city-wide lockdown and through widespread testing and an extensive set of nonpharmaceutical interventions (NPIs), such as mask wearing, contact tracing, and social distancing. We wanted to examine the effectiveness of such a policy in containing SARS-CoV-2 in the early stage of the pandemic. Therefore, we developed a fully stochastic, spatially structured, agent-based model of SARS-CoV-2 ancestral strain and reconstructed the Beijing Xinfadi outbreak through computational simulations. We found that screening for symptoms and among high-risk populations served as methods to discover cryptic community transmission in the early stage of the outbreak. Effective contact tracing could greatly reduce transmission. Targeted community lockdown and temporal mobility restriction could slow down the spatial spread of the virus, with much less of the population being affected. Population-wide mass testing could further improve the speed at which the outbreak is contained. Our analysis suggests that the containment of SARS-CoV-2 ancestral strains was certainly possible. Outbreak suppression and containment at the beginning of the pandemic, before the virus had the opportunity to undergo extensive adaptive evolution with increasing fitness in the human population, could be much more cost-effective in averting the overall pandemic disease burden and socioeconomic cost.

12.
Lancet Reg Health West Pac ; 29: 100592, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36090701

RESUMO

Background: In early March 2022, a major outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant spread rapidly throughout Shanghai, China. Here we aimed to provide a description of the epidemiological characteristics and spatiotemporal transmission dynamics of the Omicron outbreak under the population-based screening and lockdown policies implemented in Shanghai. Methods: We extracted individual information on SARS-CoV-2 infections reported between January 1 and May 31, 2022, and on the timeline of the adopted non-pharmaceutical interventions. The epidemic was divided into three phases: i) sporadic infections (January 1-February 28), ii) local transmission (March 1-March 31), and iii) city-wide lockdown (April 1 to May 31). We described the epidemic spread during these three phases and the subdistrict-level spatiotemporal distribution of the infections. To evaluate the impact on the transmission of SARS-CoV-2 of the adopted targeted interventions in Phase 2 and city-wide lockdown in Phase 3, we estimated the dynamics of the net reproduction number (Rt ). Findings: A surge in imported infections in Phase 1 triggered cryptic local transmission of the Omicron variant in early March, resulting in the largest outbreak in mainland China since the original wave. A total of 626,000 SARS-CoV-2 infections were reported in 99.5% (215/216) of the subdistricts of Shanghai until the end of May. The spatial distribution of the infections was highly heterogeneous, with 37% of the subdistricts accounting for 80% of all infections. A clear trend from the city center towards adjacent suburban and rural areas was observed, with a progressive slowdown of the epidemic spread (from 463 to 244 meters/day) prior to the citywide lockdown. During Phase 2, Rt remained well above 1 despite the implementation of multiple targeted interventions. The citywide lockdown imposed on April 1 led to a marked decrease in transmission, bringing Rt below the epidemic threshold in the entire city on April 14 and ultimately leading to containment of the outbreak. Interpretation: Our results highlight the risk of widespread outbreaks in mainland China, particularly under the heightened pressure of imported infections. The targeted interventions adopted in March 2022 were not capable of halting transmission, and the implementation of a strict, prolonged city-wide lockdown was needed to successfully contain the outbreak, highlighting the challenges for containing Omicron outbreaks. Funding: Key Program of the National Natural Science Foundation of China (82130093); Shanghai Rising-Star Program (22QA1402300).

14.
Ultrason Sonochem ; 88: 106097, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35878511

RESUMO

N-ethylcarbazole/dodecahydro-N-ethylcarbazole (NEC/H12-NEC) is a promising LOHC, and the development of a catalyst with high activity and stability is the key to realizing its reversible hydrogen storage process. In this paper, ultrafine Pd nanocrystalline catalysts (Pd/LDHs-us) supported on Cl--intercalated MgAl LDHs were prepared by a simple ultrasonic-assisted reduction method and applied in the dehydrogenation of 12H-NEC. In the process of ultrasonic-assisted reduction, the instantaneous high temperature generated by cavitation decomposed part of the CO32- in LDHs interlayer, and promoted PdCl42- to enter the interlayer and become new intercalated ions. At the same time, hydroxyl groups on the surface of LDHs were excited to generate hydrogen radicals (•H) with strong reducibility, which reduced PdCl42- to Pd nanoparticles (PdNPs) in situ. The remaining Cl- ions continued to exist in the interlayer as intercalated ions. The agglomeration of PdNPs was effectively inhibited, and the average particle size was 1.8 nm, which was uniformly dispersed on LDHs, which improved the catalytic activity of Pd/LDHs-us. The coordination between PdNPs and oxygen in the hydroxyl groups on the surface of LDHs improved its catalytic stability. Using Pd/LDHs-us catalyst, the conversion rate of H12-NEC was 100.0 %, and the dehydrogenation efficiency was 99.3 % at 180℃. When the reaction temperature drops to 170℃, the dehydrogenation efficiency can still reach 94.6 %, showing excellent catalytic performance. The study of dehydrogenation kinetics shows that the apparent activation energy of Pd/LDHs-us catalyst is only 90.97 kJ/mol. This provides a new method and idea for the preparation of efficient dehydrogenation catalysts in the future.

15.
medRxiv ; 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35765564

RESUMO

Background: In early March 2022, a major outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant spread rapidly throughout Shanghai, China. Here we aimed to provide a description of the epidemiological characteristics and spatiotemporal transmission dynamics of the Omicron outbreak under the population-based screening and lockdown policies implemented in Shanghai. Methods: We extracted individual information on SARS-CoV-2 infections reported between January 1 and May 31, 2022, and on the timeline of the adopted non-pharmacological interventions. The epidemic was divided into three phases: i) sporadic infections (January 1-February 28), ii) local transmission (March 1-March 31), and iii) city-wide lockdown (April 1 to May 31). We described the epidemic spread during these three phases and the subdistrict-level spatiotemporal distribution of the infections. To evaluate the impact on the transmission of SARS-CoV-2 of the adopted targeted interventions in Phase 2 and city-wide lockdown in Phase 3, we estimated the dynamics of the net reproduction number ( R t ). Findings: A surge in imported infections in Phase 1 triggered cryptic local transmission of the Omicron variant in early March, resulting in the largest coronavirus disease 2019 (COVID-19) outbreak in mainland China since the original wave. A total of 626,000 SARS-CoV-2 infections were reported in 99.5% (215/216) of the subdistricts of Shanghai. The spatial distribution of the infections was highly heterogeneous, with 40% of the subdistricts accounting for 80% of all infections. A clear trend from the city center towards adjacent suburban and rural areas was observed, with a progressive slowdown of the epidemic spread (from 544 to 325 meters/day) prior to the citywide lockdown. During Phase 2, R t remained well above 1 despite the implementation of multiple targeted interventions. The citywide lockdown imposed on April 1 led to a marked decrease in transmission, bringing R t below the epidemic threshold in the entire city on April 14 and ultimately leading to containment of the outbreak. Interpretation: Our results highlight the risk of widespread outbreaks in mainland China, particularly under the heightened pressure of imported infections. The targeted interventions adopted in March 2022 were not capable of halting transmission, and the implementation of a strict, prolonged city-wide lockdown was needed to successfully contain the outbreak, highlighting the challenges for successfully containing Omicron outbreaks. Funding: Key Program of the National Natural Science Foundation of China (82130093). Research in context: Evidence before this study: On May 24, 2022, we searched PubMed and Europe PMC for papers published or posted on preprint servers after January 1, 2022, using the following query: ("SARS-CoV-2" OR "Omicron" OR "BA.2") AND ("epidemiology" OR "epidemiological" OR "transmission dynamics") AND ("Shanghai"). A total of 26 studies were identified; among them, two aimed to describe or project the spread of the 2022 Omicron outbreak in Shanghai. One preprint described the epidemiological and clinical characteristics of 376 pediatric SARS-CoV-2 infections in March 2022, and the other preprint projected the epidemic progress in Shanghai, without providing an analysis of field data. In sum, none of these studies provided a comprehensive description of the epidemiological characteristics and spatiotemporal transmission dynamics of the outbreak.Added value of this study: We collected individual information on SARS-CoV-2 infection and the timeline of the public health response. Population-based screenings were repeatedly implemented during the outbreak, which allowed us to investigate the spatiotemporal spread of the Omicron BA.2 variant as well as the impact of the implemented interventions, all without enduring significant amounts of underreporting from surveillance systems, as experienced in other areas. This study provides the first comprehensive assessment of the Omicron outbreak in Shanghai, China.Implications of all the available evidence: This descriptive study provides a comprehensive understanding of the epidemiological features and transmission dynamics of the Omicron outbreak in Shanghai, China. The empirical evidence from Shanghai, which was ultimately able to curtail the outbreak, provides invaluable information to policymakers on the impact of the containment strategies adopted by the Shanghai public health officials to prepare for potential outbreaks caused by Omicron or novel variants.

16.
Front Cardiovasc Med ; 9: 807436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35557543

RESUMO

Background: Little is known regarding the quantification of sleep apnea- and hypoxemia-elicited heart rate (HR) response and its prognostic significance of the cardiovascular risk. We sought to explore the impact of HR response and variability specific to obstructive sleep apnea (OSA) on the occurrence of a common cardiovascular event - acute myocardial infarction (AMI). Methods: Consecutive patients with suspected OSA were enrolled and underwent nocturnal respiratory study and electrocardiography monitoring. The minimal oxygen saturation (minSpO2) was determined from the oxygen saturation curve under a subject-specific search window. Primary HR metrics such as maximal HR in response to minSpO2 and respiratory event-specific HR variability were computed from the synchronized recordings. Multivariate regression analyses were conducted to analyze the associations between individualized HR metrics and the occurrence of AMI. Results: Of 2,748 patients recruited, 39% (n = 1,071) had moderate-to-severe OSA (respiratory event index, REI ≥ 15), and 11.4% (n = 313) patients had AMI. Patients with AMI experienced severe OSA, severe minSpO2, and greater HR reactions. Patients with minSpO2 <90% had an adjusted odds ratio (OR) of 1.48 [95% confidence interval (CI): 1.09-2.00, p = 0.012) for AMI. Notably, minSpO2-induced elevated mean HR response (HRmean > 73 bpm) was significantly associated with AMI (OR 1.72, 95% CI: 1.32-2.23, p < 0.001). Patients with both severe minSpO2 (<90%) and elevated HRmean carried an additive OR of 2.65 (95% CI: 1.74-4.05, p < 0.001) for the risk of AMI after adjustment for potential confounders. A large total power spectrum specific to respiratory events was correlated with an adjusted OR of 0.61 for AMI risk. Conclusion: Patients with substantial HR reactions to OSA-induced oxygen nadir and restricted cardiac cycle shifting to respiratory events were likely at increased risk of developing AMI. Detection of nocturnal HR response to hypoxemia may help improve cardiovascular risk stratification.

17.
medRxiv ; 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35611330

RESUMO

We developed a spatially structured, fully stochastic, individual-based SARS-CoV-2 transmission model to evaluate the feasibility of sustaining SARS-CoV-2 local containment in mainland China considering currently dominant Omicron variants, China's current immunization level, and non-pharmaceutical interventions (NPIs). We also built a statistical model to estimate the overall disease burden under various hypothetical mitigation scenarios. We found that due to high transmissibility, neither Omicron BA.1 or BA.2 could be contained by China's pre-Omicron NPI strategies which were successful prior to the emergence of the Omicron variants. However, increased intervention intensity, such as enhanced population mobility restrictions and multi-round mass testing, could lead to containment success. We estimated that an acute Omicron epidemic wave in mainland China would result in significant number of deaths if China were to reopen under current vaccine coverage with no antiviral uptake, while increasing vaccination coverage and antiviral uptake could substantially reduce the disease burden. As China's current vaccination has yet to reach high coverage in older populations, NPIs remain essential tools to maintain low levels of infection while building up protective population immunity, ensuring a smooth transition out of the pandemic phase while minimizing the overall disease burden.

18.
Stat Med ; 41(12): 2291-2301, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35178729

RESUMO

In phase II oncology trials, two-stage design allowing early stopping for futility and/or efficacy is frequently used. However, this design based on frequentist statistical approaches could not guarantee a high posterior probability of attending the pre-specified clinically interesting rate from a Bayesian perspective. Here, we proposed a new Bayesian design enabling early terminating for efficacy as well as futility. In addition to the clinically uninteresting and interesting response rate, a prior distribution of response rate, the minimum posterior threshold probabilities and the lengths of the highest posterior density intervals were specified in the design. Finally, we defined the feasible design with the highest total effective predictive probability. We studied the properties of the proposed design and applied it to an oncology trial as an example. The proposed design ensured that the observed response rate fell within prespecified levels of posterior probability. The proposed design provides an alternative design to single-arm two-stage trials.


Assuntos
Ensaios Clínicos Fase II como Assunto , Neoplasias , Projetos de Pesquisa , Teorema de Bayes , Humanos , Oncologia , Neoplasias/tratamento farmacológico , Probabilidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-34996809

RESUMO

BACKGROUND: The relationship between maternal education and adverse pregnancy outcomes is well documented. However, limited research has investigated maternal educational disparities in adverse pregnancy outcomes in China. This study examined maternal educational inequalities associated with adverse pregnancy outcomes in rural China. METHODS: We conducted a population-based cohort study using participants enrolled in the National Free Preconception Health Examination Project in Yunnan province from 2010 to 2018. The primary outcome was stillbirth, and the secondary outcome was adverse pregnancy outcomes, defined as a composite event of stillbirth, preterm birth or low birth weight. The study was restricted to singleton births at 20-42 weeks' gestation. Univariate and multivariate log-binomial regression models were performed to estimate crude risk ratios (RRs) and confounding-adjusted RRs (ARRs) for stillbirth and adverse pregnancy outcomes according to maternal education level. RESULTS: A total of 197 722 singleton births were included in the study. Compared with mid-educated women, low-educated women were at a significantly increased risk of stillbirth (ARR, 1.20; 95% CI, 1.05 to 1.38) and adverse pregnancy outcomes (ARR, 1.11; 95% CI, 1.07 to 1.16). However, the risk of stillbirth (ARR, 1.16; 95% CI, 1.01 to 1.35) was significantly higher for high-educated women compared with mid-educated women. CONCLUSION: Compared with women with medium education level, women with lower education level were more likely to experience adverse pregnancy outcomes, including stillbirth, and women with higher education level were more likely to experience stillbirth.

20.
BMC Public Health ; 21(1): 136, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446168

RESUMO

BACKGROUND: Racial and ethnic disparities in stillbirth risk had been documented in most western countries, but it remains unknown in China. This study was to determine whether exist ethnic disparities in stillbirth risk in mainland China. METHODS: Pregnancy outcomes and ethnicity data were obtained from the National Free Preconception Health Examination Project (NEPHEP), a nationwide prospective population-based cohort study conducted in Yunnan China from 2010-2018. The Han majority and other four main minorities including Yi, Dai, Miao, Hani were investigated in the analysis. The stillbirth hazards were estimated by life-table analysis. The excess stillbirth risk (ESR) was computed for Chinese minorities using multivariable logistic regression. RESULTS: Compared with other four minorities, women in Han majority were more likely to more educated, less multiparous, and less occupied in agriculture. The pattern of stillbirth hazard of Dai women across different gestation intervals were found to be different from other ethnic groups, especially in 20-23 weeks with 3.2 times higher than Han women. The ESR of the Dai, Hani, Miao, and Yi were 45.05, 18.70, -4.17 and 12.28%, respectively. Adjusted for maternal age, education, birth order and other general risk factors, the ethnic disparity still persisted between Dai women and Han women. Adjusted for preterm birth further (gestation age <37 weeks) can reduce 16.91% ESR of Dai women and made the disparity insignificant. Maternal diseases and congenital anomalies explained little for ethnic disparities. CONCLUSIONS: We identified the ethnic disparity in stillbirth risk between Dai women and Han women. General risk factors including sociodemographic factors and maternal diseases explained little. Considerable ethnic disparities can be attributed to preterm birth.


Assuntos
Etnicidade , Nascimento Prematuro , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Estudos Prospectivos , Natimorto/epidemiologia
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