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Objective: To systematically evaluate the diagnostic value of nucleic acid test in sputum for COVID-19 and to determine the suitable population for sputum specimens. Method(s): PubMed, CNKI, Scopus, Web of Science, medRxiv and bioRxiv databases were searched for the diagnostic value of sputum nucleic acid test for COVID-19 from December 2019 to April 2022. Two researchers independently screened the literature, extracted data, and evaluated the risk of bias with QUADAS-2 in the included studies. We used sensitivity, specificity, AUC and DOR to evaluate the diagnostic value of sputum specimens. Result(s): A total of 25 studies were included, including 10,731 subjects. Meta-analysis results showed that: The combined sensitivity (SEN), specificity (SPE), diagnostic odds ratio (DOR), and area under operating characteristic curve (AUC) of sputum nucleic acid for the diagnosis of COVID-19 were 89.2% (95% CI, 86.6-91.4), 97.5% (95% CI, 97.2-97.8), 41.4 (95% CI, 11.7-145.9), 0.9474 (95% CI, 0.8964-0.9846). The results of subgroup analysis showed that the Asian group's DOR was 36.835 (95% CI, 10.83-134.570), and the Non-Asian group's DOR was 66.294 (95% CI, 0.719-6109.09). The DOR was 27.207 (95% CI, 2.860-258.780) in the OPS group and 44.165 (95% CI, 4.828-403.970) in the NPS group. DOR of mild patients was 84.255 (95% CI, 9.975-711.690), the DOR of the severe group was 14.216 (95% CI, 3.527-57.142) and was 19.464 (95% CI, 0.724-522.920) in the cured group. Conclusion(s): Current evidence shows that sputum nucleic acid test is of high diagnostic value for COVID-19. Study area and severity of disease are the influencing factors for the diagnostic accuracy of the sputum nucleic acid test. Due to the limitations on the number and quality of the included studies, the above conclusions need to be verified by more high-quality studies.Copyright © 2023, E-Century Publishing Corporation. All rights reserved.
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The coronavirus disease 2019 (COVID-19) pandemic underlines a persistent threat of respiratory tract infectious diseases and warrants preparedness for a rapid response. At present, COVID-19 has had a serious social impact and imposed a heavy global burden on public health. The exact pathogenesis of COVID-19 has not been fully elucidated. Since the outbreak of COVID-19, a renewed attention has been brought to Toll-like receptors (TLRs). Available data and new findings have demonstrated that the interaction of human TLRs and SARS-CoV-2 is a vital mediator of COVID-19 immunopathogenesis. TLRs such as TLR2, 4, 7 and 8 are potentially important in viral combat and activation of immunity in patients with COVID-19. Therapeutics targeting TLRs are currently considered promising options against the pandemic. A number of TLR-targeting immunotherapeutics are now being investigated in preclinical studies and different phases of clinical trials. In addition, innovative vaccines based on TLRs under development could be a promising approach for building a new generation of vaccines to solve the current challenges. In this review, we summarize recent progress in the role of TLRs in COVID-19, focusing the new candidate drugs targeting TLRs, the current technology and potential paths forward for employing TLR agonists as vaccine adjuvants.Copyright © 2023 The Scandinavian Foundation for Immunology.
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Introduction: In March 2020, Malaysia initiated the first Movement Control Order (MCO) to curb the spread of COVID-19 infections. While healthcare services remained operational, fears of contracting COVID-19 may have impacted health seeking behaviours and healthcare access. A survey was conducted to investigate how the first MCO impacted actions of individuals experiencing upper respiratory tract infection versus other symptoms, routine follow-up visits, and refill prescription practices. Method(s): A cross-sectional survey among adult Malaysians was conducted from November to December 2020. A selfadministered questionnaire was developed, validated, and disseminated on social media and communication platforms. Result(s): 3001 participants responded to the survey. 486 (16.0%) of them reported being unwell during the MCO. Regardless of symptoms, actions taken to seek medical care were similar. The most common action on average was visiting a medical doctor (55.0%), followed by self-medicating at home (38.0%). 588 participants had a scheduled appointment for their medical condition during the MCO. 253 of them had their appointments affected by the lockdown, for examples, 85.0% postponed, 12% cancelled, 9.0% referred. Only 42.3% of these affected participants saw a doctor within 3 months after the first MCO. Out of 487 participants who regularly collected medications from the pharmacy, 69.0% had a prescription refill appointment during the lockdown. Only 15.0% of them did not collect their medications on the scheduled date. Conclusion(s): The first MCO did not severely affect health seeking behaviour and prescription refill practices. However, there are concerns over timely access to follow-up appointments due to extensive rescheduling and backlogs triggered by the pandemic.
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We study how robotization, namely the "machine substitution” policy, impacts firms' labour demand in the post pandemic era. Using a unique firm-level data set of online job postings in Dongguan, known as "The World Factory” in China, we find that "machine substitution” policy fosters the funded firms to expand their labour demand. The expansion is mainly driven by the growing demand for manufacturing workers, which offsets the reduced demand for service workers. Also, the expansion can be attributed to an increase in the number of employees listed in job postings rather than an increase in position types. Further analysis suggests that this positive impact is mainly attributable to the productivity effect rather than the restatement effect. Furthermore, there is no evidence of heterogeneity by sector or firm size but the effect of the policy varies by regional epidemic severity. Our results not only reveal the labour demand in the Covid-19 but also provide prominent implications for occupational security and steady economic growth. © 2023 Elsevier Inc.
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The lack of social activities in the elderly for physical reasons can make them feel lonely and prone to depression. With the spread of COVID-19, it is difficult for the elderly to conduct the few social activities stably, causing the elderly to be more lonely. The metaverse is a virtual world that mirrors reality. It allows the elderly to get rid of the constraints of reality and perform social activities stably and continuously, providing new ideas for alleviating the loneliness of the elderly. Through the analysis of the needs of the elderly, a virtual social center framework for the elderly was proposed in this study. Besides, a prototype system was designed according to the framework. The elderly can socialize in virtual reality with metaverse-related technologies and human-computer interaction tools. Additionally, a test was jointly conducted with the chief physician of the geriatric rehabilitation department of a tertiary hospital. The results demonstrated that the mental state of the elderly who had used the virtual social center was significantly better than that of the elderly who had not used it. Thus, virtual social centers alleviated loneliness and depression in older adults. Virtual social centers can help the elderly relieve loneliness and depression when the global epidemic is normalizing and the population is aging. Hence, they have promotion value © 2022 Beijing Zhongke Journal Publishing Co. Ltd
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Objective: To evaluate the immunogenicity effect of CpG 7909 and Alum adjuvant to inactivated SARS-CoV-2 vaccine. Method(s): Mice were immunized with inactivated SARS-CoV-2 vaccines prepared with CpG 7909 and/or Alum adjuvant by intramuscular injection for 0 and 21 days. To evaluate the immunogenicity of inactivated SARS-CoV-2 vaccines with different adjuvants, serum samples were collected on Day 14, 28, 35 and 42 after immunization to detect the neutralizing antibody titers by microneutralization assay. Spleen samples were collected on Day 42 after immunization to detect the cellular immunity by flow cytometry and ELISPOT. Result(s): Compared with the inactivated SARS-CoV-2 vaccines adjuvanted with CpG 7909 or Alum only, the combination of CpG 7909 and Alum adjuvant significantly increased neutralizing antibody titers in mice and showed great cross-neutralization activity against the Delta variant. It also significantly induced the activation of specific IL-4, IFN-gamma and GCB cells. Conclusion(s): The combination of CpG 7909 and Alum adjuvant synergistically enhanced the humoral and cellular immune responses induced by inactivated SARS-CoV-2 vaccine and showed great cross-neutralization activity against the Delta variant. Copyright © 2022, Chinese Journal of New Drugs Co. Ltd. All right reserved.
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Introduction: Our knowledge of genetic contributions to malignancy risk has increased greatly over the past two decades. It is now known that BRCA1 gene mutation is associated with a 50% lifetime risk of developing malignancy.Women who carry a BRCA1 mutation have a 47-66% lifetime risk of developing breast cancer, a 63% chance of developing cancer in the contralateral breast at 25 years, and a 35-46% lifetime risk of developing ovarian cancer.1,2 BRCA1 mutation carriers also have increased rates of pancreatic cancer (odds ratio [OR], 2.26), leukemia, and lymphomas (OR, 2.6).3,4 There is conflicting evidence regarding the effect of BRCA1 mutation on a patient's risk of developing colorectal cancer, but it may increase the risk up to 1.5 times.5,6 Independent of known genetic syndromes, cancer survivors are 14% more likely to be diagnosed with a new malignancy than those who have not had a previous cancer.1 Patients with colorectal cancer at stage two or three have a 40% recurrence rate after primary therapy, with more than 90% of recurrences occurring within the first 5 years.7 Transformation of follicular lymphoma to diffuse large B-cell lymphoma (DLBCL) occurs in up to 24% of cases, although it is less common in patients who have achieved clinical remission. Overall, this improved knowledge has resulted in increased surveillance for recurrence and associated malignancies. Case report: A 77-year-old woman underwent colonoscopy after lymphoma surveillance screening incidentally revealed a positron emission tomography-avid cecal lesion. This was on a background of previous colorectal cancer, managed with a left hemicolectomy and adjuvant chemotherapy with 5-fluorouracil and leucovorin in 1995. The patient was overdue for colonoscopy surveillance due to delays attributed to the COVID-19 pandemic. She was asymptomatic, with no weight loss, fevers, or night sweats. She denied change in bowel habit, with daily motions without the presence of tenesmus, melena, or rectal bleeding. Her past medical history was also significant for known BRCA1 positivity, which was diagnosed following bilateral breast cancer, affecting the right breast in 1981 and left breast in 1991. This was treated with bilateral mastectomy and axillary dissection. The patient received prophylactic hysterectomy and bilateral salpingo-oophorectomy in 2000. She previously had stage IIIa low-grade follicular lymphoma and received six cycles of bendamustine plus rituximab in 2018 and was considered in remission, with ongoing 6-monthly surveillance imaging. The patient's other medical conditions included metabolic syndrome, gastroesophageal reflux disease, osteoporosis, depression, left lacunar infarct, epilepsy, and cataracts. Examination revealed a non-tender abdomen with central adiposity. There was no palpable abdominal mass or evidence of hepatosplenomegaly or lymphadenopathy. She had a normal cardiovascular and respiratory examination. Colonoscopy showed a large two-thirds circumferential non-obstructing mass in the cecum. There was no evidence of bleeding, and the mass was biopsied. Histology showed that atypical lymphoid cells were present at an ulcer base with surrounding necrotic tumor cells. These cells were strongly positive for BCL2, CD45, CD20, and CD79a within the nodular lymphoid aggregate and negative for AE1/3 and CAM5.2. This appearance was consistent with a diagnosis of high-grade DLBCL. The patient had her care transferred to her hematologist, who confirmed a diagnosis of DLBCL and instigated six cycles of modified R-CHOP regimen for chemotherapy. Conclusion(s): This is a rare case of colorectal lymphoma and illustrates the well-documented risk of progression from follicular lymphoma to the more sinister DLBCL. It highlights the complexity of cancer genetics, justifies the increased need for malignancy surveillance within these groups, and confirms the importance of biopsy for all abnormal colorectal lesions.
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Since the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the number of SARS-CoV-2 infections has been increasing and health care is facing huge challenges. Innovative drug development in emergency and the development of new indications for the treatment of Coronavirus disease 2019 (COVID-19) on the market have become critical to finding effective drugs and optimal treatment options for COVID-19. The angiotensin converting enzyme 2 (ACE2) -inducing mechanism of SARS-CoV-2 invasion into host cells and the potential therapeutic targets based on SARS-CoV-2 and (or) host include RNA-dependent RNA polymerase, 3-chymotrypsin-like protease, papain like protease, Janus kinase, interleukine-6 and immune modulators etc. Based on the pharmacological mechanism mentioned above the clinical research and development of new indications and innovative drugs for the treatment of COVID-19 have achieved great progress, but no specific drugs have been found. Some traditional Chinese medicines can block the SARS-CoV-2 replication cycle, regulate human immune response and play an important role in the treatment of COVID-19. The new drugs for COVID-19 are undergoing Phase I clinical studies worldwide, and biologic drugs are gaining momentum, accounting for 67% of the total. The problems with the research and development of drugs for COVID-19 treatment in China include inadequate of biological safety laboratories, less research on SARS-CoV-2 reacting mechanisms, shortages of non-clinical cells and animal models, imperfect research platforms for quantitative pharmacological research and training systems of professionals and poor levels of informatization of drug clinical trials and sample detection. It is hoped that China can take this opportunity to improve the ability to develop new drugs in emergency and better protect human health.
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Objective To explore the application and safety of apheresis technology in collection of Coronavirus Disease 2019 (COVID-19) convalescent plasma (CP), and to analyze the quality characteristics of the plasma. Methods The general data of COVID-19 convalescent plasma (CP) donors, including gender, age, date of discharge or release from medical isolation, were collected based on informed consent. After physical examination, the CP was collected by apheresis technology with plasma separator, inactivated with methylene blue, and determined for severe acute respiratory symptom Coronavirus 2 (SARS-CoV-2) nucleic acid and specific antibody (RBD-IgG) against SARS-CoV-2. Results The collection process went well, and no serious adverse events related to plasma collection were reported during or after the collection. The average age of COVID-19 CP donors was 38 years (n = 933). The distributions of blood groups A, B, AB and 0 in RhD (+) COVID-19 CP were 33. 4%, 29. 2%, 10% and 27. 2% respectively. The plasma donation date was 18 d from the discharge date in average. All the test results of SARS-CoV-2 nucleic acid in CP were negative, while the proportion of plasma samples at SARS-CoV-2 antibody titer of more than 1: 160 was 92. 60%. Conclusion Apheresis technology was safe and reliable. The COVID-19 CP contained high titer antibody. Large-scale collection and preparation of inactivated plasma against SARS-CoV-2 played an important role in the treatment of COVID-19.
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Many universities have incorporated free and open-source software (FOSS) into undergraduate courses, though few research efforts have specifically investigated the interactions between undergraduates and real-world FOSS projects. In this paper, we present our experience of participating in the development of real-world FOSS projects, dealing with the challenges caused by COVID-19, and the feasibility of remote education with FOSS only. Our experience shows that undergraduates and FOSS projects can help each other well. Moreover, we summarize the strengths and weaknesses of the existing FOSS communities in attracting undergraduates and provide some suggestions. © 2021 Association for Computing Machinery.
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The COVID-19 pandemic has had a severe impact on humans' lives and and healthcare systems worldwide. How to early, fastly and accurately diagnose infected patients via multimodal learning is now a research focus. The central challenges in this task mainly lie on multi-modal data representation and multi-modal feature fusion. To solve such challenges, we propose a medical knowledge enriched multi-modal sequence to sequence learning model, termed MedSeq2Seq. The key components include two attention mechanisms, viz. intra-modal (Ia) and inter-model (Ie) attentions, and a medical knowledge augmentation mechanism. The former two mechanisms are to learn multi-modal refined representation, while the latter aims to incorporate external medical knowledge into the proposed model. The experimental results show the effectiveness of the proposed MedSeq2Seq framework over state-of-the-art baselines with a significant improvement of 1%-2%. © 2021 IEEE.
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Background: Among the regions in China, Shanghai has took the lead in proposing the establishment of fever alertness clinics in community health centers. As a component of the epidemic control and prevention system, fever alertness clinics assume the role of containing an epidemic at the primary level. The Public Health Preparedness Clinic(PHPC) is a branch of Singapore's sound public health system. Objective: To compare fever alertness clinics of Shanghai and Singapore's PHPCs, then put forward suggestions to improve the construction of Shanghai's fever alertness clinics. Methods: This study was carried out from December 2020 to April 2021. For studying Shanghai's fever alertness clinics, policy documents analysis, literature review and field survey were used. Besides, interviews were also used, which were conducted in two rounds, separately for managers and healthcare workers who were selected from a random sample of three fever alertness clinics(one in the central urban area, one in the outer suburb and one in the urban fringe) of Shanghai. Guided by different outlines, the interviews for the two groups were aimed to collect their perspectives of the organizational structure, setting, operation, and management of fever alertness clinics. For studying Singapore's PHPCs and relevant practice, literature review was used. Results: The number and density of PHPC in Singapore are higher than those in Shanghai fever alertness clinic. Shanghai has higher standards for setting up fever alertness clinic, but PHPCs in Singapore has a higher entry threshold. Shanghai fever alertness clinic have more specific treatment procedures and standardization. Singapore's PHPC system is more prominent in terms of subsidies for epidemic prevention and protection of medical staff. Conclusion: The construction of Singapore's PHPCs needs longer preparation time, and the government is responsible for setting standards, admittance approval, planning and layout using the top-down approach, so the development of PHPCs shows higher homogeneity and meticulousness. In contrast, the construction of fever alertness clinics in Shanghai started late, showing higher personalized and localized characteristics. Copyright © 2021 by the Chinese General Practice.
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The novel coronavirus pneumonia, a global pandemic disease named as coronavirus disease 2019, has caused enormous losses on the health and economies of people all over the world, while there is still a lack of quick and sensitive diagnostic method and effective therapy. Developing rapid diagnostic method for coronavirus disease 2019 has become exceptional urgent. Herein we report a rapid diagnostic method for the novel coronavirus through monitoring the volatile biomarkers in human exhaled breath. The breath volatile biomarkers are derived from the metabolism of novel coronavirus, including acetoin, 2,4,6-trimethylpyridine, 3-methyl tridecane, tetradecane, isooctyl alcohol, pentadecane, hexadecane, 1-methylene-1H-indene. By comparing the types and concentrations of the volatile biomarkers in human exhaled breath combined with SERS sensor, we could distinguish between the healthy person and the patients with coronavirus disease 2019. This work confirms that various volatile organic compounds metabolized by novel coronavirus can be employed for rapidly screening of patients with coronavirus disease 2019, and has broad application prospects in the prevention and control of the epidemic.
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Background: Since the outbreak of COVID-19, the ability to manage public health emergencies in mega-cities has been put on the policy agenda, and the role of primary care in public health system is critical. Objective: To explore the status, problems and challenges of practical exploration of Shanghai's primary care in responding to COVID-19, providing policy recommendations and decision-making basis for improving the public health emergency system. Methods: From June to September 2020, a qualitative study was conducted using group interviews with administrators and healthcare professionals selected from 10 representative community health centers(CHCs) in suburban, fringe and urban areas in Shanghai's 5 districts for exploring major tasks shouldered by the CHCs, organizational structure of the CHCs, actual tasks performed by the CHCs, internal collaboration, major problems in service delivery during the pandemic, and recommendations, and with directors, as well as professionals responsible for information, healthcare management and quality control, public emergency management and infectious disease containment selected from health commissions and centers for disease control and prevention in the districts, for exploring the functions and roles of CHCs during the pandemic and their weaknesses in anti-pandemic actions, anti-pandemic supports from health commissions and centers for disease control and prevention for CHCs, and ideas about actions of primary care in pandemic and non-pandemic periods. The interviews with individuals from three kinds of affiliations were guided using different types of semi-structured outlines developed by our research team. Results: The interviews revealed that during the pandemic, the CHCs gave emergency responses to COVID-19, participated in regional collaboration for COVID-19 containment, delivered in-hospital COVID-19 screening and triage services while providing routine medical services, and continued to offer family doctor services. Four issues were found to be addressed: insufficient healthcare resources and workers, insufficient services targeting psychological influence of COVID-19, unsatisfied internal coordination and multi-departmental management, and lack of appropriate mechanisms incentivizing healthcare workers and invigorating primary care. Conclusion: In view of the challenges in fighting COVID-19 faced by primary care, it is recommended to take actions on the basis of appropriately balancing the delivery of routine primary care services and public health services, and tasks during pandemic and non-pandemic periods, and appropriately coordinating with higher level departments, as well as developing incentive programs according to the local conditions as a supplement for the government programs. Copyright © 2021 by the Chinese General Practice.
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Purpose: To alleviate the effects of coronavirus disease 2019 (COVID-19) on the economy, Taiwan introduced a stimulus package in the form of triple stimulus vouchers. Despite intense promotion to opt for the vouchers in digital form, Taiwanese public overwhelmingly chose the paper form. This study considers the reasons that influenced their decision comfort in choosing paper rather than digital vouchers based on two categories: rational (promotion depth and ease of use) and behavioral economics factors (analysis paralysis, mental accounting related to ease of tracking expenses, social influence and payment habits). Design/methodology/approach: Partial least squares (PLS) method was utilized to analyze survey information obtained from 183 individuals who chose paper vouchers. Findings: Individuals consider rational and behavioral economic factors in their perception of decision comfort while choosing paper over digital vouchers. Decision comfort is driven more by behavioral economics than rational factors such as ease of use. Interestingly, analysis paralysis related to paper vouchers has the greatest impact, but it positively influences decision comfort, indicating that Taiwanese people view paper vouchers as a safe haven in the midst of uncertainties and information overload. Therefore, when designing public policies or promotional campaigns, possible behavior outcomes should be considered from both rational and behavioral economic perspectives. Originality/value: This study provides insights into the dynamics of how individuals arrive at their decision of opting paper vouchers over digital ones and offers theoretical contributions related to system adoption and behavioral economics. © 2021, Emerald Publishing Limited.
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Mental health conditions pose a major challenge for individuals, healthcare systems and society-and the COVID-19 pandemic has likely worsened this issue. According to the Mental Health Foundation of New Zealand, one in five people will develop a serious mood disorder, including depression, at some time in their life. Co-designed solutions to increase resilience and well-being in young people have specifically been recognised as part of the National Suicide Prevention Strategy and the New Zealand Health Strategy. Virtual Reality (VR) in mental health is an innovative field. Recent studies support the use of VR technology in the treatment of anxiety, phobia, and pain management. However, there is little research on using VR for supporting, treating and preventing depression. There is also very little work done in offering an individualised VR experience to improve mental health. In our earlier work, we presented iVR, a novel individualised VR experience for enhancing peoples' self-compassion, and in the long run, their mental health, and described its design and architecture. In this paper, we outline the results of a feasibility study conducted recently. Most participants believed introducing elements of choice within iVR enhanced their user experience and that iVR had the potential to enhance people's self-compassion. We also approached seven mental health professionals for feedback, who felt that introducing elements of choice within iVR would increase their knowledge of clients. Our contribution can pave the way for large-scale efficacy testing, clinical use, and cost-effective delivery of intelligent individualised VR technology for mental health therapy in future. © 2021 ACM.
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Because SARS-COV2 entry into cells is dependent on angiotensin converting enzyme 2 (ACE2) and angiotensin converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) increase ACE2 activity, the safety of ACEI/ARB usage during the coronavirus disease 2019 (COVID-19) pandemic is a controversial topic. To address that issue, we performed a meta-analysis following The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Searches of the Embase, MEDLINE, PubMed, and Cochrane Library databases identified 16 case-control studies examining the effect of ACEI/ARB on the incidence of COVID-19 and its severity. ACEI/ARB usage was associated with an increased risk of COVID-19 morbidity (odds ratio (OR) 1.20, 95% confidence interval (CI) 1.07-1.33, P=0.001) among the general population but not in a hypertensive population (OR 1.05, 95% CI 0.90-1.21, P=0.553). ACEI/ARB usage was not associated with an increased risk of COVID-19 morbidity (coefficient 1.00, 95% CI 1.00-1.00, P=0.660) when we adjusted for hypertension in the general population. ACEI/ARB usage was also not associated with an increased risk of severe illness (OR 0.90, 95%CI 0.55-1.47, P=0.664) or mortality (OR 1.43, 95%CI 0.972.10, P=0.070) in COVID-19 patients. Our meta-analysis revealed that ACEI/ARB usage was not associated with either the increased risk of SARS-COV2 infection or the adverse outcomes in COVID-19 patients.
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Objective: To investigate and analyze the epidemiological characteristics of a cluster of coronavirus disease 2019 (COVID-19) spread by a super spreader in Taizhou, Zhejiang Province, and provide reference for prevention and control of COVID-19. Methods: The field epidemiological investigation was conducted to investigate the confirmed cases and close contacts;the data were analyzed with descriptive method. Chi-squared test was used to compare the differences of attack rates among close contacts. Results: A total of 23 epidemiological related cases were identified, including 20 confirmed cases and 3 asymptomatic infection cases. Thirteen (56.52%) were males, ten (43.48%) were females, and the median age was 51 years old with the range of 30 to 70 years old. The second generation case firstly developed symptoms on Jan 19th and was confirmed on Jan 30th, 2020.The first generation cases were from Wuhan and the last case was confirmed on Feb 3rd, 2020.The epidemic spread to the fifth generation with a total attack rate of 6.07% (21/346), among which the third generation case was a super spreader who directly transmitted to 12 subsequent cases with a significantly higher attack rate than other cases (27.27% vs. 2.98%, χ2=39.754, P<0.001). Conclusion: The expansion of the epidemic can be attributed to the lack of timely control of imported personnel from high risk regions, the lacking awareness of novel infectious diseases at the early stage of the epidemic and the appearance of the super spreader. To form a normalized prevention mechanism, it is necessary to improve the alertness of novel infectious diseases among medical staffs and the masses, implement prevention and control strategies in time. © 2021, Editorial Department of Fudan University Journal of Medical Sciences. All right reserved.
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The novel coronavirus disease (COVID-19) is breaking out and spreading rapidly around the world. There is an urgent need for an accurate and rapid detection method to quickly find infected patients and asymptomatic carriers in order to prevent the spread of the severe acute respiratory syndrome coronavirus [SARS-CoV-2]. In this paper, we designed a test strip which used the principle of double antigen sandwich. Fe3O4 magnetic nanobeads are firstly coupled with specific antibodies, and the S protein of the new coronavirus is used as the coating antigen to capture specific antibodies against the new coronavirus, which is used to detect the virus nucleoprotein of specific antibodies in clinical samples. At the same time, Fe3O4 magnetic nanobeads have unique magnetic properties, which can be used to generate different types of detection signals and simplify the detection process. These results can be judged by color changes and magnetic changes at the test and control lines. Compared with the traditional method, this test strip of Fe3O4 magnetic nanobeads has high sensitivity and can qualitatively detect samples within 15 minutes. The magnetic performance of the magnetic nanobeads can be used to improve the sensitivity of the strip in our further research and product development.