Rapid detection of mpox virus using recombinase aided amplification assay

A recent, unprecedented outbreak of human mpox virus infection has led to cases in non-African nations, and the number of confirmed or suspected cases outside of Africa has exceeded 1,000 within 5 weeks. Mpox may pose a double threat to public health in the context of the ongoing COVID-19 pandemic. It is difficult to distinguish mpox virus infection from other diseases in the early stages, and patients are contagious from the onset of nonspecific symptoms;therefore, it is crucial to develop rapid and specific diagnostic methods. The diagnosis of mpox relies on real-time polymerase chain reaction, a time-consuming method that requires a highly sophisticated thermal cycler, which makes it unsuitable for widespread use in underdeveloped areas, where the outbreak is still severe. In this study, we developed a recombinase-aided amplification (RAA) assay that can detect mpox virus within 5–10 minutes. The conserved regions of the A27L gene and F3L gene were selected as targets, as they amplify well from different mpox virus clades with no cross-reaction from other pathogens. The sensitivity of this RAA assay is 10 copies/reaction for the A27L gene and 102 copies/reaction for the F3L gene. When applied to simulated clinical samples, both targets showed 100% specificity, and the detection limits were consistent with the sensitivity results. Moreover, through clinical blinded sample detection, RAA exhibits the same detection power as RT-PCR. In summary, the RAA mpox assay described here exhibits rapid detection, high sensitivity and specificity, and low operational difficulty, making it suitable for mpox virus detection in less developed countries and regions.

Rapid detection of mpox virus using recombinase aided amplification assay.

A recent, unprecedented outbreak of human mpox virus infection has led to cases in non-African nations, and the number of confirmed or suspected cases outside of Africa has exceeded 1,000 within 5 weeks. Mpox may pose a double threat to public health in the context of the ongoing COVID-19 pandemic. It is difficult to distinguish mpox virus infection from other diseases in the early stages, and patients are contagious from the onset of nonspecific symptoms; therefore, it is crucial to develop rapid and specific diagnostic methods. The diagnosis of mpox relies on real-time polymerase chain reaction, a time-consuming method that requires a highly sophisticated thermal cycler, which makes it unsuitable for widespread use in underdeveloped areas, where the outbreak is still severe. In this study, we developed a recombinase-aided amplification (RAA) assay that can detect mpox virus within 5-10 minutes. The conserved regions of the A27L gene and F3L gene were selected as targets, as they amplify well from different mpox virus clades with no cross-reaction from other pathogens. The sensitivity of this RAA assay is 10 copies/reaction for the A27L gene and 102 copies/reaction for the F3L gene. When applied to simulated clinical samples, both targets showed 100% specificity, and the detection limits were consistent with the sensitivity results. Moreover, through clinical blinded sample detection, RAA exhibits the same detection power as RT-PCR. In summary, the RAA mpox assay described here exhibits rapid detection, high sensitivity and specificity, and low operational difficulty, making it suitable for mpox virus detection in less developed countries and regions.

Impact of Vaccination and Control Measures on the Fatality of COVID-19: An Ecological Study.

BACKGROUND: During the COVID-19 pandemic, reducing the case fatality rate (CFR) becomes an urgent goal. OBJECTIVE: This study explored the effect of vaccination and variants on COVID-19 fatality and provide a basis for the adjustment of control measures. METHODS: This study collected epidemiological information on COVID-19 from January to October 2021. By setting different lag times, we calculated the adjusted CFR. The Spearman correlation coefficient and beta regression were used to explore factors that may affect COVID-19 fatality. RESULTS: Every 1% increase in the percentage of full vaccinations may reduce the 3 weeks lagging CFR by 0.66%. Increasing the restrictions on internal movement from level 0 to 1, restrictions on international travel controls from level 2 to 3, and stay-at-home restrictions from level 0 to 2 were associated with an average reduction in 3 weeks lagging CFR of 0.20%, 0.39%, and 0.36%, respectively. Increasing strictness in canceling public events from level 0 to 1 and 2 may reduce the 3 weeks lagging CFR by 0.49% and 0.37, respectively. Increasing the severity of school and workplace closures from level 1 or level 0 to 3 may increase the 3 weeks lagging CFR of 0.39% and 0.83, respectively. Every 1-point increase in the Global Health Security (GHS) index score may increase the 3 weeks lagging CFR by 0.12%. CONCLUSION: A higher percentage of full vaccinations, higher levels of internal movement restrictions, international travel control restrictions, cancelations of public events, and stay-at-home restrictions are factors that may reduce the adjusted CFR.

Management for stroke intelligent early warning empowered by big data.

Global aging population, especially with the global pandemic outbreak of the Corona Virus Disease 2019 (COVID-19), has endangered human health security. Digital information technology through big data empowerment and intelligent application is widely considered a key element to solve the problems. Stroke is a life-threaten disorder. We studied individual health management and disease risk perception using human health assessment model and make full use of wearable wireless sensor, Internet of Things, big data, and Artificial Intelligence for potential risk monitoring and real-time stroke warning. We proposed an effective method of monitoring, early warning and rescue to improve the stroke treatment. The result shows that the health management empowered by big data can generate new opportunities and ideas to solve early detection and warning of stroke.

Development of a Loop-Mediated Isothermal Amplification Method for Rapid and Visual Detection of Monkeypox Virus.

Monkeypox virus (MPXV) is a human pathogenic virus that belongs to the genus Orthopoxvirus. In 2022, MPXV caused an unprecedented number of infections in many countries. As it is difficult to distinguish MPXV from other pathogens by its symptoms in the early stage of infection, a rapid and reliable assay for MPXV detection is needed. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay for the specific detection of MPXV and evaluated its application in simulated clinical samples. The A27L-1 and F3L-1 primer sets were identified as the optimal primers, and 63°C was the most appropriate reaction temperature for sequence amplification. The detection limits of the LAMP assay using primer sets A27L-1 and F3L-1 were both 20 copies/reaction mixture, which were >100-fold higher in terms of sensitivity, compared with conventional PCR. The LAMP assay findings were negative for all 21 non-MPXV pathogens, confirming the high specificity of our assay. All three types of simulated clinical samples were clearly identified by our LAMP assay, and the detection limits were consistent with the sensitivity results, indicating efficient clinical sample identification. Our rapid and reliable MPXV LAMP assay could be useful for MPXV detection and on-site diagnosis, especially in primary hospitals and rural areas. IMPORTANCE MPXV outbreaks rapidly grew in the first half of 2022, and this virus has been recognized as an increasing public health threat, particularly in the context of the COVID-19 pandemic. Thus, developing reliable and fast detection methods for MPXV is necessary.

Does potential antibody-dependent enhancement occur during SARS-CoV-2 infection after natural infection or vaccination? A meta-analysis.

Coronavirus disease 2019 (COVID-19) continues to constitute an international public health emergency. Vaccination is a prospective approach to control this pandemic. However, apprehension about the safety of vaccines is a major obstacle to vaccination. Amongst health professionals, one evident concern is the risk of antibody-dependent enhancement (ADE), which may increase the severity of COVID-19. To explore whether ADE occurs in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and increase confidence in the safety of vaccination, we conducted a meta-analysis to investigate the relationship between post-immune infection and disease severity from a population perspective. Databases, including PubMed, EMBASE, Chinese National Knowledge Infrastructure, SinoMed, Scopus, Science Direct, and Cochrane Library, were searched for articles on SARS-CoV-2 reinfection published until 25 October 2021. The papers were reviewed for methodological quality, and a random effects model was used to analyse the results. Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated using a funnel plot and Egger's test. Eleven studies were included in the final meta-analysis. The pooled results indicated that initial infection and vaccination were protective factors against severe COVID-19 during post-immune infection (OR = 0.55, 95%CI = 0.31-0.98). A subgroup (post-immune infection after natural infection or vaccination) analysis showed similar results. Primary SARS-CoV-2 infection and vaccination provide adequate protection against severe clinical symptoms after post-immune infection. This finding demonstrates that SARS-CoV-2 may not trigger ADE at the population level.

Does COVID-19 have an impact on influenza vaccine knowledge, attitude and practice among medical students: a 2-year prospective cohort study.

OBJECTIVES: To explore the main factors affecting the knowledge, attitude and practice about influenza and influenza vaccine as well as the intention to receive influenza vaccination among the same group of medical students before (2019) and after (2021) the COVID-19 outbreak. DESIGN: A population-based prospective cohort study. SETTING: A longitudinal cohort study of a selected medical school in Chongqing, China, which ran from 2019 to 2021. PARTICIPANTS: A total of 803 medical students participated in the study in 2019 and only 484 students responded in 2021. The response rate for our survey was only 60.27% due to graduation, emails being abandoned, etc. RESULTS: The influenza vaccination rate of students at this medical school was 6.7% in 2019, compared with 25.8% in 2021. The awareness rate of medical students about influenza and influenza vaccine was 82.8% in 2019 and 86% in 2021, and there was no significantly statistical difference between the 2 years (p=0.134); the number of medical students with supportive attitude towards influenza vaccine was 95.1% in 2019 and 97.1% in 2021, and there was no statistically significant difference between the 2 years (p=0.078); the number of students who actively learnt about knowledge related to influenza vaccine rose from 183 (22.8%) in 2019 to 195 (40.3%) in 2021. CONCLUSIONS: The COVID-19 outbreak prompted an increase in influenza vaccination rates among medical students in Chongqing, with almost all students (96.0%) believing that the spread of COVID-19 promoted their knowledge about influenza and influenza vaccine, and the vast majority (74.8%) believing that the spread of COVID-19 promoted their willingness to receive influenza vaccine.

Association between Mutations in Papain-like Protease (PLpro) of SARS-CoV-2 with COVID-19 Clinical Outcomes.

Papain-like protease (PLpro) is important for the replication and transcription of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to reveal the PLpro mutations associated with the clinical outcomes of patients. Due to the importance of the S protein in the pathogenicity of SARS-CoV-2, the mutation of the S protein was also analyzed in this study. After downloading the data from the Global Initiative on Sharing Avian Influenza Data (GISAID) database, samples were divided into two groups on the basis of patient status, namely, recovered and dead groups. This study performed a univariate analysis and further explored the association of mutations with patient outcomes through multivariate logistic regression analysis. A total of 138,492 samples were used for analysis. The patients had a mean age of 43.66 ± 21.56 years, and 51.3% of them were female. Multivariate logistic regression results showed that, compared with men, women had a lower risk of dying from coronavirus disease 2019 (COVID-19) (OR = 0.687, 95%CI: 0.638-0.740). Compared with patients aged 17 years and younger, patients aged 18-64 years (OR = 2.864, 95%CI: 1.982-4.139) and patients over 65 years old (OR = 19.135, 95%CI: 13.280-27.572) had a higher risk of death after infection. Compared with the wild type, P78L (OR = 5.185, 95%CI: 2.763-9.730) and K233Q (OR = 5.154, 95%CI: 1.442-18.416) in PLpro were associated with an increased risk of death. A synergistic interaction existed between age and mutations A146D and P78L. The results of the multivariate logistic regression analysis of the data on vaccinated patients demonstrated that, compared with the wild type, the P78L (OR = 3.376, 95%CI: 2.040-5.585) mutation was associated with an increased risk of death. In conclusion, compared with the wild-type PLpro protein, the P78L and K233Q mutations may increase the risk of death in infected individuals. In addition, a synergistic effect existed between age and P78L and K233Q that increased the risk of death in older patients.

[Psychological Status and Influencing Factors of Staff at Centers for Disease Control and Prevention in Sichuan Province during the Outbreak of Coronavirus Disease 2019].

Objective To assess the psychological status of staff at the centers for disease control and prevention(CDC) in Sichuan during the outbreak of coronavirus disease 2019(COVID-19) and explore the influencing factors. Methods The staff at Sichuan provincial,municipal,and county(district)-level CDC were selected by convenience sampling.Their basic information,work status,training status,work difficulties,and support from the work group were collected from the self-filled questionnaires online.The Generalized Anxiety Disorder Scale and the 9-question Patient Health Questionnaire were respectively employed to measure the anxiety and depression of the staff.The stepwise Logistic regression was carried out to analyze the influencing factors of anxiety and depression in CDC staff. Results Among the 653 staff,58.35% and 50.06% presented anxiety and depression,respectively.The regression results showed that age(OR=0.95,95%CI=0.92-0.97) and mental support from the work group(OR=0.61,95%CI=0.45-0.82) were the protective factors while physical fatigue(OR=1.82,95%CI=1.20-2.74),work pressure(OR=1.61,95%CI=1.21-2.12),and insufficient protective equipment(OR=1.92,95%CI=1.06-3.49) were the risk factors for depression of CDC staff.Age(OR=0.97,95%CI=0.94-0.99),length of sleep per day(OR=0.74,95%CI=0.56-0.96),and participation in technical training(OR=0.33,95%CI=0.12-0.95) were the protective factors while mental fatigue(OR=1.68,95%CI=1.18-2.41),work pressure(OR=2.94,95%CI=2.08-4.17),and unclear incentive system for overtime(OR=1.99,95%CI=1.23-3.23) were the risk factors for the anxiety of CDC staff. Conclusion The anxiety and depression status of CDC staff during the COVID-19 outbreak were worrying,which were mainly affected by age,sleep,supply of protective equipment,incentive system,fatigue,and work pressure.

Effectiveness of inactivated SARS-CoV-2 vaccines against the Delta variant infection in Guangzhou: a test-negative case-control real-world study.

The effectiveness of inactivated SARS-CoV-2 vaccines against the Delta variant, which has been associated with greater transmissibility and virulence, remains unclear. We conducted a test-negative case-control study to explore the vaccine effectiveness (VE) in real-world settings. We recruited participants aged 18-59 years who consisted of SARS-CoV-2 test-positive cases (n = 74) and test-negative controls (n = 292) during the outbreak of the Delta variant in May 2021 in Guangzhou city, China. Vaccination status was compared to estimate The VE of SARS-CoV-2 inactivated vaccines. A single dose of inactivated SARS-CoV-2 vaccine yielded the VE of only 13.8%. After adjusting for age and sex, the overall VE for two-dose vaccination was 59.0% (95% confidence interval: 16.0% to 81.6%) against coronavirus disease 2019 (COVID-19) and 70.2% (95% confidence interval: 29.6-89.3%) against moderate COVID-19 and 100% against severe COVID-19 which might be overestimated due to the small sample size. The VE of two-dose vaccination against COVID-19 reached 72.5% among participants aged 40-59 years, and was higher in females than in males against COVID-19 and moderate diseases. While single dose vaccination was not sufficiently protective, the two-dose dosing scheme of the inactivated vaccines was effective against the Delta variant infection in real-world settings, with the estimated efficacy exceeding the World Health Organization minimal threshold of 50%.

Willingness to Receive SARS-CoV-2 Vaccination and Associated Factors among Chinese Adults: A Cross Sectional Survey.

Vaccination is a key strategy to prevent the pandemic caused by the coronavirus disease 2019 (COVID-19). This study aims to investigate the willingness of Chinese adults to be vaccinated against COVID-19 and further explore the factors that may affect their willingness. We used a self-design anonymous questionnaire to conduct an online survey via the Sojump. A total of 1009 valid questionnaires were analyzed. The age of the participants ranged from 18 to 74. Among them, 609 (60.4%, 95%CI: 57.4-63.4%) were willing to receive the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. Logistic regression analysis results showed that the age of 30-49 (OR = 2.042, 95%CI: 1.098-3.799), universities and colleges education (OR = 1.873, 95% CI = 1.016-3.451), master degree or above education (OR = 1.885, 95%CI = 1.367-2.599), previous influenza vaccination history (OR = 2.176, 95%CI: 1.474-3.211), trust in the effectiveness of the vaccine (OR = 6.419, 95%CI: 3.717-11.086), and close attention to the latest news of the vaccine (OR = 1.601, 95%CI: 1.046-2.449) were facilitative factors that affected their willingness to be vaccinated. More than half of the adults in China would be willing to receive a SARS-CoV-2 vaccine. Middle-aged people with higher education, those who had been vaccinated against influenza, and those who believed that COVID-19 vaccine was effective and paid close attention to it were more willing to be vaccinated. Our findings can provide reference for the implementation of vaccination and the prevention of COVID-19 in China. More studies are needed after the vaccine is launched.

Retrospective study identifies infection related risk factors in close contacts during COVID-19 epidemic.

OBJECTIVES: This study aimed to compare the risk of infection of children with that of adults and to explore risk factors of infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) by following up close contacts of COVID-19 patients. METHOD: The retrospective cohort study was performed among close contacts of index cases diagnosed with COVID-19 in Guangzhou, China. Demographic characteristics, clinical symptoms and exposure information were extracted. Logistic regression analysis was employed to explore the risk factors. The restricted cubic spline was conducted to examine to the dose-response relationship between age and SARS-CoV-2 infection. RESULTS: The secondary attack rate (SAR) was 4.4% in 1,344 close contacts. The group of household contacts (17.2%) had the highest SAR. The rare-frequency contact (p < 0.001) and moderate-frequency contact (p < 0.001) were associated with lower risk of infection. Exposure to index cases with dry cough symptoms was associated with infection in close contacts (p = 0.004). Compared with children, adults had a significantly increased risk of infection (p = 0.014). There is a linear positive correlation between age and infection (p = 0.001). CONCLUSIONS: Children are probably less susceptible to COVID-19. Close contacts with frequent contact with patients and those exposed to patients with cough symptoms are associated with an increased risk of infection.

Comparative analysis of clinical characteristics, imaging and laboratory findings of different age groups with COVID-19.

Objective: This study aims to provide scientific basis for rapid screening and early diagnosis of the coronavirus disease 2019 (COVID-19) through analysing the clinical characteristics and early imaging/laboratory findings of the inpatients. Methods: Three hundred and three patients with laboratory-confirmed COVID-19 from the East Hospital of People's Hospital of Wuhan University (Wuhan, China) were selected and divided into four groups: youth (20-40 years, n = 64), middle-aged (41-60 years, n = 89), older (61-80 years, n = 118) and elderly (81-100 years, n = 32). The clinical characteristics and imaging/laboratory findings including chest computed tomography (CT), initial blood count, C-reactive protein [CRP]), procalcitonin (PCT) and serum total IgE were captured and analysed. Results: (1) The first symptoms of all age groups were primarily fever (76%), followed by cough (12%) and dyspnoea (5%). Beside fever, the most common initial symptom of elderly patients was fatigue (13%). (2) Fever was the most common clinical manifestation (80%), with moderate fever being the most common (40%), followed by low fever in patients above 40 years old and high fever in those under 40 years (35%). Cough was the second most common clinical manifestation and was most common (80%) in the middle-aged. Diarrhoea was more common in the middle-aged (21%) and the older (19%). Muscle ache was more common in the middle-aged (15%). Chest pain was more common in the youth (13%), and 13% of the youth had no symptoms. (3) The proportion of patients with comorbidities increased with age. (4) Seventy-one per cent of the patients had positive reverse transcription-polymerase chain reaction results and 29% had positive chest CT scans before admission to the hospital. (5) Lesions in all lobes of the lung were observed as the main chest CT findings (76%). (6) Decrease in lymphocytes and increase in monocytes were common in the patients over 40 years old but rare in the youth. Eosinophils (50%), red blood cells (39%) and haemoglobin (40%) decreased in all age groups. (7) The proportion of patients with CRP and PCT elevation increased with age. (8) Thirty-nine per cent of the patients had elevated IgE, with the highest proportion in the old (49%). Conclusion: The clinical characteristics and imaging/laboratory findings of COVID-19 patients vary in different age groups. Personalised criteria should be formulated according to different age groups in the early screening and diagnosis stage.