Infectivity, susceptibility, and risk factors associated with SARS-CoV-2 transmission under intensive contact tracing in Hunan, China

BackgroundSeveral parameters driving the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain unclear, including age-specific differences in infectivity and susceptibility, and the contribution of inapparent infections to transmission. Robust estimates of key time-to-event distributions remain scarce as well. MethodsWe collected individual records for 1,178 SARS-CoV-2 infected individuals and their 15,648 contacts identified by contact tracing and monitoring over the period from January 13 to April 02, 2020 in Hunan Province, China. We provide descriptive statistics of the characteristics of cases and their close contacts; we fitted distributions to time-to-key-events distributions and infectiousness profile over time; and we used generalized linear mixed model to estimate risk factors for susceptibility and transmissibility of SARS-CoV-2. ResultsWe estimated the mean serial interval at 5.5 days (95%CI -5.0, 19.9) and the mean generation time at 5.5 days (95%CI 1.7, 11.6). The infectiousness was estimated to peak 1.8 days before symptom onset, with 95% of transmission events occurring between 7.6 days before and 7.3 days after the date of symptom onset. The proportion of pre-symptomatic transmission was estimated to be 62.5%. We estimated that at least 3.5% of cases were generated asymptomatic individuals. SARS-CoV-2 transmissibility was not significantly different between working-age adults (15-59 years old) and other age groups (0-14 years old: p-value=0.16; 60 years and over: p-value=0.33), whilst susceptibility to SARS-CoV-2 infection was estimated to increase with age (p-value=0.03). In addition, transmission risk was higher for household contacts (p-value<0.001), decreased for higher generations within a cluster (second generation: odds ratio=0.13, p-value<0.001; generations 3-4: odds ratio=0.05, p-value<0.001, relative to generation 1), and decreased for infectors with a larger number of contacts (p-value=0.04). InterpretationOur findings warn of the possible relevant contribution of children to SARS-CoV-2 transmission. When lockdown interventions are in place, we found that odds of transmission are highest in the household setting but, with the relaxation of interventions, other settings (including schools) could bear a higher risk of transmission. Moreover, the estimated relevant fraction of pre-symptomatic and asymptomatic transmission highlight the importance of large-scale testing, contact tracing activities, and the use of personnel protective equipment during the COVID-19 pandemic.

Hospitalization burden of hand, foot and mouth disease in Anhua county of Hunan province,2013-2016 / 中华流行病学杂志

Objective To estimate the serotype and age-specific hospitalization burden associated with hand,foot and mouth disease (HFMD) in Anhua county of Hunan province,between October 2013 and September 2016.Methods We collected hospitalization records of HFMD patients from 6 virological surveillance hospitals,and reimbursement records through new rural cooperative medical system from 23 township health centers to estimate the age-specific hospitalization burden of HFMD in Anhua.Combined with the results of virological surveillance,the serotype-specific hospitalization burden of HFMD in Anhua,was estimated.Results During the three years,it was estimated that 3 541 clinical diagnosed HFMD cases,including 3 146 laboratory-confirmed HFMD cases,were hospitalized in Anhua,but only one was diaguosed as being severe.The estimated average hospitalization rate was 723/100 000(95％C1:699/100 000-747/100 000) for clinical diagnosed HFMD and 642/100 000 (95％ CI:620/100 000-665/100 000) for laboratory-confirmed HFMD between October 2013 and September 2016.The cases caused by Cox A16 (208/100 000) and Cox A6 (202/100 000) had higher hospitalization rates compared with the cases caused by EV71 (130/100 000),Cox A10 (38/100 000) and other enterovirus (64/100 000),and the difference was statistically significant (P＜0.001).HFMD-associated hospitalization rates peaked in children aged 1 year (3 845/100 000),and then decreased with age.Compared with the hospitalized HFMD caused by EV71 and Cox A16,Cox A6-associated hospitalizations mainly occurred in younger age groups (P＜0.001).Conclusion Our study revealed a substantial hospitalization burden associated with mild HFMD caused by EV71,Cox A16,Cox A6 and Cox A10,especially in young children,in Anhua.

Hospitalization burden of hand, foot and mouth disease in Anhua county of Hunan province,2013-2016 / 中华流行病学杂志

Objective To estimate the serotype and age-specific hospitalization burden associated with hand,foot and mouth disease (HFMD) in Anhua county of Hunan province,between October 2013 and September 2016.Methods We collected hospitalization records of HFMD patients from 6 virological surveillance hospitals,and reimbursement records through new rural cooperative medical system from 23 township health centers to estimate the age-specific hospitalization burden of HFMD in Anhua.Combined with the results of virological surveillance,the serotype-specific hospitalization burden of HFMD in Anhua,was estimated.Results During the three years,it was estimated that 3 541 clinical diagnosed HFMD cases,including 3 146 laboratory-confirmed HFMD cases,were hospitalized in Anhua,but only one was diaguosed as being severe.The estimated average hospitalization rate was 723/100 000(95％C1:699/100 000-747/100 000) for clinical diagnosed HFMD and 642/100 000 (95％ CI:620/100 000-665/100 000) for laboratory-confirmed HFMD between October 2013 and September 2016.The cases caused by Cox A16 (208/100 000) and Cox A6 (202/100 000) had higher hospitalization rates compared with the cases caused by EV71 (130/100 000),Cox A10 (38/100 000) and other enterovirus (64/100 000),and the difference was statistically significant (P＜0.001).HFMD-associated hospitalization rates peaked in children aged 1 year (3 845/100 000),and then decreased with age.Compared with the hospitalized HFMD caused by EV71 and Cox A16,Cox A6-associated hospitalizations mainly occurred in younger age groups (P＜0.001).Conclusion Our study revealed a substantial hospitalization burden associated with mild HFMD caused by EV71,Cox A16,Cox A6 and Cox A10,especially in young children,in Anhua.

Molecular cloning and expression of a serine protease family from Jellyfish Cyanea capillata / 中国生化药物杂志

Objective To obtain a single toxin component from the jellyfish Cyanea capillata and provide a foundation for the further study on bioactivity and function of the serine proteases from C.capillata.Methods Primers designed with restriction enzyme were used to amplify the coding region of cDNAs (CcSP1, CcSP2 and CcSP3).PCR fragments were ligated with the pET-24a( +) vector to construct the recombinant plasmids (pET24a-CcSP1, pET24a-CcSP2 and pET24a-CcSP3).After screening and identification,the recombinant plasmids were transformed into the Rosetta (DE3).plysS for protein expression.After induction with IPTG, SDS-PAGE and Western-blot were used to detect the expression of the recombinant proteins.Results SDS-PAGE showed that the proteins of rCcSP1, rCcSP2 and rCcSP3 were expressed in a single band at about 34 kDa, 42 kDa and 42kDa, respectively.Western-blot detection with anti-His antibody further confirmed that these recombinant proteins were His-tagged CcSP1, CcSP2 and CcSP3 fusion protein were obtained.Conclusion Prokaryotic recombinant plasmids of C.capillata serine proteases are contructed and recombinant proteins are obtained, which establishes the foundation for future study on the function of serine proteases from jellyfish.

Progresses on marine antimicrobial activity proteins / 中国生化药物杂志

Due to the particularity of marine ecological environment, many marine lives have developed and accumulated a large amount of biological molecules with special chemical structures and physiological activities, representing an important resource for the development of marine drugs. Generally, the marine antibacterial proteins are mainly identified from the marine microorganisms, invertebrates and fish.In this review, the progresses on marine antibacterial peptides and antimicrobial activity proteins are briefly summarized.

Discussion on releasing price of Chinese patent medicine to market economy to achieve sustainable development / 中国中药杂志

<p><b>OBJECTIVE</b>To analyze costs of the traditional Chinese medicine industry focusing on production costs.</p><p><b>METHOD</b>Data of 50 planted Chinese herbal medicines and 50 wild Chinese herbal medicines were summarized and analyzed to see the changes of price of Chinese herbal medicines.</p><p><b>RESULT</b>The derivative problems of limited price were analyzed by crude drug, quality of Chinese medicine and sustainable utilization of resource.</p><p><b>CONCLUSION</b>The price of Chinese medicine shall be adapted to sustainable development of market economy.</p>

Study on pollen viability and stigma receptivity of 5 Iris plants / 中国中药杂志

<p><b>OBJECTIVE</b>To increase the reproduction efficiency of Iris plants.</p><p><b>METHOD</b>Pollen viability, stigmatic receptivity, the color of anther and stigma of 5 Iris plants were observed during blooming.</p><p><b>RESULT</b>1. The highest pollen viability was in 4 hours after blooming; 2. The stigmatic receptivities of I. sichuanensis, I. leptophylla, I. lactea and I. goniocarpa were strong in 4 hours after blooming, while that of I. lactea var. chinensis was strong in 2 hours after blooming; 3. The color of anther could reflect the pollen viability, but could not indicate the viability level; 4. The stigma color could not reflect the receptivity of stigma.</p><p><b>CONCLUSION</b>The optimum artificial pollination time of these five species were 12:00 -14:00.</p>

Effect of Fujian Tablet on expression of axon guidance factor in rat after cerebral infarction / 中华中医药杂志

Objective: To explore the mechanism of Fujian Tablet in promoting neural regeneration by observing the effect of Fujian Tablet on the expression of slit in MCAO rats at different stages. Methods: 240 SD rats were randomly divided into normal control, sham operation, model and medicine groups, which were randomly divided into five subsets with 12 rats according to the day 3 and week 1, 2, 4, 6 stages. The rat models with middle cerebral artery occlusion were successfully established by the improved Longa EZ. The medicine group was gived with Fujian Tablet, other groups were given with commensurability distilled water. The expession of slit in the region around the infarction was observed by immunohistochemical method. Results: In the medicine group, slit -positive cells were obviously different with normal control group (P

Characteristics of B-ultrasonic renal changes in chronic aristolochic acid nephropathy / 中华肾脏病杂志

Objective To observe the B- ultrasonic (B-US) renal changes of chronic aristolochic acid nephropathy (CAAN) patients and to determine its value in disease diagnosis. Methods The renal B-US data of 124 CAAN patients were retrospectively studied. The relationship between the B-US characteristics and the renal function was tested. Clinicopathological data of 19 CAAN patients underwent renal biopsy were compared with those of 18 patients with chronic tubulointerstitial nephropathy due to none-aristolochic acid causes (non-AAN-CTIN). Results The characteristics of renal B-US changes in CAAN patients included diminished parenchyma thickness (90.3%), atrophy of the kidney (62.90%) and asymmetrically shrinked kidneys (17.74%). The renal B-US markers, including the longitude, the volume and the parenchyma thickness, were closely associated with the level of Scr, eGFR and the function of renal tubules (P

Morphological effect of bushen yiqi huoxue formula on articular cartilage tissue in rabbits with experimental osteoarthritis of knee / 中国组织工程研究

BACKGROUND: At present, osteoarthritis of knee is mainly treated with non-steroid drug in medication, but resulting in the side effects on gastrointestinal tract. The research indicates that bushen yiqi huoxue formula, with litter side effect, improves remarkably pain and motor function of patients with osteoarthritis of knee.OBJECTIVE: To probe into the effect of bushen yiqi huoxue formula on pathological process of the cartilage of knee joint by setting up ostoarthritis of knee in rabbt.DESIGN: Randomized controlled study by observation in which the experimental animals were taken as the objects.SETTING: Animal experimental center of a university.MATERIALS: Totally 36 New Zealand normal male rabbits, weighted varied from 2.0 to 3.0 kg.METHODS: The experiment was performed in Animal Experimental Center of Guangzhou University of Chinese Medicine from January 2002 to January 2003. Thirty-six New Zealand rabbits were involved to set up Hulth knee osteoarthritis model. After operation, they were randomized into 3 groups,named as model group, acetaminophen group and bushen yiqi huoxue formula group (formula group). Adopted corresponding managements in each group,the materials were collected at the 4th, 8th and 12th week after operation for histological pathological assess.MAIN OUTCOME MEASURES: Primary results: integrals of pathological changes in cartilage of joint in every group. Secondary results: ①Naked-eye observation of cartilage of joint in every group. ② Optic microscopic observation of cartilage of joint in every group.RESULTS: The total integrals of pathological changes in cartilage of joint in model group, acetaminophen group and bushen yiqi huoxue formula grcup (formula group) at the 4th week were 18.50±1.00, 14.25±1.26,11.75±2.22 respectively, and 30.75±1.26, 22.00±3.16, 17.75±2. 21 at the 12th week respectively. The total integrals of pathological changes in cartilage of joint, in chondrocyte and in cartilage surface layer are in the sequence of model group ＞ acetaminophen group ＞ formula group successively. The significant or very significant differences present in the comparisons between groups.CONCLUSION: Bushen yiqi huoxue formula delays pathological progression of osteoarthritis of knee so that it can treat and prevent the disease.

Comments on treatment of severe acute respiratory syndrome by integrated traditional Chinese and western medicine / 中西医结合学报

There are obvious advantages of the integrated traditional Chinese and western medicine on the treatment of severe acute respiratory syndrome (SARS). Combining the ancient and present literature with the special epidemic patterns, pathological changes and clinical symptoms of SARS, the paper discussed the methods of application of the integrated traditional Chinese and western medicine on the treatment of SARS, and some matters needing attention in clinic.

The Spondylolysis of Lumbar Spine:CT Diagnosis,Its Clinical Signifieance and the Improvement of Technique of CT Scan / 实用放射学杂志

Objective To evaluate the diagnostic value of CT in the spondylolysis of lumbar spine and improve the technique of CT scan.Methods The CT appearances of the spondylolysis of lumbar spine were analyzed in 20 cases.Results CT could demonstrate the spondylolysis and its abnormal features that led to compress nerve root.Conclusion CT scan plays an important role in the diagnosis of the spondylolysis of lumbar spine and in selecting treat methods.Technique of CT scan improved can depict the specific feature of spondylolysis truely.

Effect of Fujian Tablets on Expression of Microtubule-associated Protein 2 in Cerebral Infarction Rats at Different Time Points / 广州中医药大学学报

Objective To observe the effect of Fujian Tablets(FT),a prescription with the actions of nourishing liver and kidney,on the expression of microtubule-associated protein 2(MAP-2) in cerebral infarction rats at different time points,and to explore its mechanism on promoting nerve cell differentiation.Methods A total of 240 male Sprague Dawley rats were divided into normal control group,sham-operation group,model group and FT group.Focal cerebral ischemia models were established by occlusion of the middle cerebral artery according to the reformed Longa method in rats,and were subdivided into 3-,7-,14-,28-,and 42-day cerebral infarction subgroups.FT group was given FT in the dose of 9 g?kg-1?d-1,and the other groups were given the same dose of distilled water.Results In the model group,MAP-2 expression in the hippocampus increased and reached a peak on day 3,which were notably different from that in the normal control group(P0.05).In FT group,MAP-2 expression increased on day 3,reached a peak on day 7,remained high level till day 14,and then decreased,the difference being significant compared with the model group(P

Occupational exposure of medicine and safety protection measures / 中华医院管理杂志

With reference to medical personnel's infection during the prevalence of SARS, the paper offers some general information on the risks of occupational exposure of medicine. The commonly seen risks fall into four major categories, including biological risks, such as infection of hepatitis B, hepatitis C, HTV, etc.; chemical risks, such as those from antineoplastic drugs, cleaning agents, disinfectants, narcotics, dusts; physical risks, such as radiation, injury by sharp instruments, injury from heavy burden, forced body positions, etc.; and psychological risks. The paper also puts forward some proposals for safety protection: intensifying training in occupational safety of medicine, reinforcing the protection of high-risk groups of people and high-risk body parts, augmenting the supply of protective materials and the improvement of protective facilities, and setting up and perfecting long-acting protection and supply mechanisms.

Intelligence Scale for Chinese Adult: Development of National Norms with Urban Samples / 中国心理卫生杂志

Objective: To develop the national norms of ISCA (intelligence scale for Chinese adult) for urban adults aged 16 to 64 years and examine its psychometric characteristics. Methods:The ISCA standardization was completed on 1600 adult subjects. Year 2000 Census data was applied to the standardization sample in order to correctly represent individuals by age, gender, educational level, geographic region, and occupation. Results:The ISCA had good reliability( test-retest coefficients of Full scale IQ was 0.96, the average spilt-half reliability for the IQ scales ranged from 0.93 to 0.96 and the average standard error of measurement of subtest ranged from 1.04~1.88, rater reliability 0.91~0.96). The total score of ISCA relates that of the WAIS-RC, WAIS-III revised in Taiwan, and CRT-C2 are 0.94, 0.90, 0.69, respectively (P