Study on Control Techniques of Virus Diseases in Facility Cherry

The diseases of sweet cherry caused by viruses and viroids have occurred in the main cherry producing areas of China and are increasing year by year, which has become an important factor affecting the yield and quality of sweet cherry. For this reason, this paper elaborated the prevention and countermeasures of virus diseases from six aspects, including soil treatment, cultivation of disease-free seedlings, prevention of disease and pest damage, reasonable pruning, water management, and treatment of virus diseases, in order to provide technical guidance for the disease resistance, high quality and high yield of facility cherry, as well as information reference for the further improvement of the technical system of virus disease prevention and cultivation of facility cherry.

Prevalence Characteristics of Rice Black-streaked Dwarf Virus Disease and Continuous Control Strategies

Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.

Research Progress and Prospect on Prevention and Control Measures of Sweet Potato Virus Disease

Sweet potato virus disease is a serious biological threat to sweet potato,which seriously affects the development of sweet potato industry in China.This paper gives a brief introduction to the main defensive measures of sweet potato virus disease,such as cutting of virus infection source,killing of viral transmission media,cultivation and application of virus-free sweet potato,use of antiviral agents,breeding of varieties with virus resistance,and mild strain cross protection,so as to provide some reference for this field.

Identification and Control of Radish Alternaria Leaf Spot, Black Rot, Soft Rot, Virus Disease and Hollowness

The damage characteristics and occurrence regularity of radish alternaria leaf spot, black rot, soft rot, virus disease and hollowness are introduced in the paper, and the corresponding control method is proposed from two aspects of agricultural control and chemical control.

Prevention and Control Strategies of Nosocomial Infection and Effectiveness Evaluation in a Tertiary Teaching Hospital during the Epidemic of COVID-19

Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital initiated an emergency plan involving multi-departmental defense and control. It adopted a series of nosocomial infection prevention and control measures, including strengthening pre-examination and triage, optimizing the consultation process, improving the hospital’s architectural composition, implementing graded risk management, enhancing personal protection, and implementing staff training and supervision. Descriptive research was used to evaluate the short-term effects of these in-hospital prevention and control strategies. The analysis compared changes in related evaluation indicators between January 24, 2020 and February 12, 2020 (Chinese Lunar New Year’s Eve 2020 to lunar January 19) and the corresponding lunar period of the previous year. Results: Compared to the same period last year, the outpatient fever rate increased by 1.85-fold (P P Conclusion: The nosocomial infection prevention and control strategies implemented during this specific period improved the detection and control abilities for the COVID-19 source of infection and enhanced the compliance with measures. This likely contributed significantly to avoiding the occurrence of nosocomial infection.

Control Effects of Different Agents on Tobacco Mosaic Virus Disease

[Objectives] This study was conducted to screen out suitable agents for controlling tobacco mosaic virus disease and the best control period in Zhangzhou tobacco area, providing a theoretical basis for the control of virus diseases, thereby improving the quality of flue-cured tobacco and the income of tobacco farmers. [Methods] The effects on tobacco mosaic virus disease under the interaction between different agents and different application periods were investigated. The incidence of tobacco mosaic virus disease was investigated, and its control effect was analyzed. [Results] Different agents and different application periods had different control effects on tobacco mosaic virus disease. The incidence of tobacco mosaic virus disease: At 30 and 45 d after transplanting, the incidences of A2B1 treatment were the lowest, at 0.85%, 1.71%, respectively;and at 60 d after transplanting, the incidence of A3B1 treatment was the lowest, only 10.68%. The control effect: At 30 and 45 d after transplanting, A2B1 treatment had better control effects, reaching 79.39% and 73.06%, respectively. [Conclusions] 3% hypersensitive protein sprayed at 1 d before transplanting and 7 and 15 d after transplanting achieved the best effect, followed by 10% ningnanmycin sprayed at 1 d before transplanting and 7 and 15 d after transplanting. In tobacco production, it is recommended to apply 1 000 times dilution of 3% supersensitive protein microgranules for three times(at 1 d before transplanting and 7 and 15 d after transplanting), which can effectively prevent tobacco mosaic virus disease.

Main Diseases of Zucchini and Their Prevention and Control Methods

This paper elaborates the symptom characteristics and control methods of virus diseases including squash leaf curl china virus(SLCCNV),watermelon mosaic virus(WMV),cucurbit chlorotic yellows virus(CCYV),cucumber mosaic virus(CMV)and zucchini yellow mosaic virus(ZYMV),as well as fungal diseases including zucchini powdery mildew,zucchini downy mildew and zucchini scab that harm zucchini production,in order to provide a theoretical basis and technical support for disease prevention and control of zucchini.

Study on the Effective Prevention and Control of Maize Rough Dwarf Disease in Different Areas with Varying Epidemic Intensity in Shandong Province

[ Objective] This study aimed to investigate the effective prevention and control of maize rough dwarf disease in different areas with varying epidemic inten-sity in Shandong Province. [Method] Control effects of single application of virus in-hibitors and composite application of virus inhibitors with seed dressing agents and pesticides on maize rough dwarf disease in different areas with varying epidemic intensity were investigated. [Result] The same treatment possessed entirely different effects in severely affected areas and slightly affected areas. To be specific, single application of virus inhibitors in slightly affected areas exhibited good control effects, with a control efficiency of 76.59% and yield increment rate of 158.21%; in severely affected areas, single application of virus inhibitors led to low control efficiency and yield increment rate. The highest control efficiency of composite application of virus inhibitors with seed dressing agents and pesticides in severely affected areas was 71.38%, and experimental plots changed from total crop failure to have certain eco-nomic output. [Conclusion] ln different areas with varying epidemic intensity of maize rough dwarf disease, different application modes should be adopted according to lo-cal conditions, thereby saving cost and improving control efficiency.

Effects of Biological Pesticides on Prevention and Treatment of Virus Diseases in Greenhouse Tomato in Autumn

To alleviate the damage of tomato virus diseases, reduce chemical pesticide consumption and residue, and prevent environmental pollution, forecasting, randomized block design and statistical analysis were adopted to conduct field efficacy tests for Lentinan ＋ Gibberellin-heteroauxin-brassinolide （GHB） and Ningnanmycin ＋ GHB. The results showed that when the virus diseases in greenhouse tomato were serious, 0.5% Lentinan AS 3 000 ml ＋ GHB WP 600 g and 8% Ningnanmycin AS 900 ml ＋ GHB WP 600 g per hectare were applied 4 times with an interval of 7 days, and the control effects on the 10th, 17th, 26th and 35th day were above 88%, 87%, 78% and 67%, respectively. The difference in control effect of the two biological pesticides was insignificant, while their control effects were all significantly better than that of moroxydine hydrochloride （CK） ＋ GHB. The obtained results indicated that Lentinan ＋ GHB and Ningnanmycin ＋ GHB were the ideal biological pesticides, which could be used not only for controlling tomato virus diseases, but also for realizing modern, pollution-free, green and organic agricultural production.

Obstetrical Surgery in the Context of Ebola Virus Disease (Ebola) in Guinea: Lessons Learned from 2 Cases

In this manuscript, the authors have studied obstetrical surgery in the context of Ebola virus disease in Guinea. No protocol recommends childbirth outside of Ebola treatment center, although it has no technical platform and no qualified providers in this area. These were unknown MVE cases in pregnant women/parturient women aged 25 and 40 years, with no education, who were confirmed in the RT-PCR test after surgical management. To fight Ebola virus transmission, traditional protection protocols must be strengthened. Training, supervision and monitoring of providers are key elements for the protection of staff in the event of an EVD outbreak. Improving working conditions and strengthening hand washing, usage of PPE/EPP, decontamination of equipment with 0.5% chlorine solution, hygiene of premises, immunization of personnel involved, are effective measures to combat EVD.

A review on the Ebola virus,outbreak history and the current research tools to control the disease

The Ebola virus is a zoonotic pathogen causing hemorrhagic fever disease with a high mortality rate.The distribution of this pathogen has been limited to woodlands from Central and West Africa and the forest-savannah ecotone in East Africa.The likely reservoir species are frugivorous bats living in these areas.This pathogen is becoming an increasing threat to human populations since its distribution range is expanding faster than expected.The current Ebola outbreaks in Western Africa and in the Democratic Republic of Congo have rapidly spread infecting high numbers of individuals in five African countries.The disease has reached the United States and Spain.This expansion is due partly to increasing global connectivity.This situation represents a new challenge to control the spread of the disease.Experimental drugs have been used to treat a few infected people with promising results.This gives hope for an effective treatment against Ebola hemorrhagic fever in the near future,though thousands of people remain at risk of infection.The present review aims to give an update of the knowledge on the disease,including features of the Ebola virus,the history of disease outbreaks in Africa and the tools that are being developed in order to control this re-emergent disease.

Optimal control analysis of Ebola disease with control strategies of quarantine and vaccination

Background:The 2014 Ebola epidemic is the largest in history,affecting multiple countries in West Africa.Some isolated cases were also observed in other regions of the world.Method:In this paper,we introduce a deterministic SEIR type model with additional hospitalization,quarantine and vaccination components in order to understand the disease dynamics.Optimal control strategies,both in the case of hospitalization(with and without quarantine)and vaccination are used to predict the possible future outcome in terms of resource utilization for disease control and the effectiveness of vaccination on sick populations.Further,with the help of uncertainty and sensitivity analysis we also have identified the most sensitive parameters which effectively contribute to change the disease dynamics.We have performed mathematical analysis with numerical simulations and optimal control strategies on Ebola virus models.Results:We used dynamical system tools with numerical simulations and optimal control strategies on our Ebola virus models.The original model,which allowed transmission of Ebola virus via human contact,was extended to include imperfect vaccination and quarantine.After the qualitative analysis of all three forms of Ebola model,numerical techniques,using MATLAB as a platform,were formulated and analyzed in detail.Our simulation results support the claims made in the qualitative section.Conclusion:Our model incorporates an important component of individuals with high risk level with exposure to disease,such as front line health care workers,family members of EVD patients and Individuals involved in burial of deceased EVD patients,rather than the general population in the affected areas.Our analysis suggests that in order for R0(i.e.,the basic reproduction number)to be less than one,which is the basic requirement for the disease elimination,the transmission rate of isolated individuals should be less than one-fourth of that for non-isolated ones.Our analysis also predicts,we need high levels of medication and hospitalization at the beginning of an epidemic.Further,optimal control analysis of the model suggests the control strategies that may be adopted by public health authorities in order to reduce the impact of epidemics like Ebola.

Modeling transmission dynamics of Ebola virus disease

Ebola virus disease （EVD） has emerged as a rapidly spreading potentially fatal disease. Several studies have been performed recently to investigate the dynamics of EVD. In this paper, we study the transmission dynamics of EVD by formulating an SEIR-type transmission model that includes isolated individuals as well as dead individuals that are not yet buried. Dynamical systems analysis of the model is performed, and it is consequently shown that the disease-free steady state is globally asymptotically stable when the basic reproduction number, R0 is less than unity. It is also shown that there exists a unique endemic equilibrium when R0 〉 1. Using optimal control theory, we propose control strategies, which will help to eliminate the Ebola disease. We use data fitting on models, with and without isolation, to estimate the basic reproductive numbers for the 2014 outbreak of EVD in Liberia and Sierra Leone.

Occult hepatitis B virus infection is not associated with disease progression of chronic hepatitis C virus infection

AIM To clarify the prevalence of occult hepatitis B virus(HBV) infection(OBI) and the association between OBI and liver disease progression, defined as development of liver cirrhosis or hepatocellular carcinoma(HCC), worsening of Child-Pugh class, or mortality in cases of chronic hepatitis C virus(HCV) infection. METHODS This prospective cohort study enrolled 174 patients with chronic HCV infection(chronic hepatitis, n = 83; cirrhosis, n = 47; HCC, n = 44), and evaluated disease progression during a mean follow-up of 38.7 mo. OBI was defined as HBV DNA positivity in 2 or moredifferent viral genomic regions by nested polymerase chain reaction using 4 sets of primers in the S, C, P and X open reading frame of the HBV genome. RESULTS The overall OBI prevalence in chronic HCV patients at enrollment was 18.4%, with 16.9%, 25.5% and 13.6% in the chronic hepatitis C, liver cirrhosis and HCC groups, respectively(P = 0.845). During follow-up, 52 patients showed disease progression, which was independently associated with aspartate aminotransferase > 40 IU/L, Child-Pugh score and sustained virologic response(SVR), but not with OBI positivity. In 136 patients who were not in the SVR state during the study period, OBI positivity was associated with neither disease progression, nor HCC development. CONCLUSION The prevalence of OBI in chronic HCV patients was 18.4%, and OBI was not associated with disease progression in South Koreans.

Study on Screening of Virus Inhibitor Combinations against Viral Diseases in Chinese Cabbage

In this study, several kinds of virus inhibitors or passivators, such as Dufulin and lentinan, were used to design 15 individual or combination treatments, to investigate their control efficiency against viral diseases in Chinese cabbage. Re- sults showed that individual treatments of Dufulin and lentinan achieved high control efficiency of 70.01% and 66.02%, respectively; combination treatments of Dufulin ＋ lentinan, Dufulin ＋ Weijiaxi and Lentinan ＋Weijiaxi also produced certain synergistic effects, with control efficiency of 83.70%, 78.07% and 82.32%, respectively.

河南郑州桃园桃病毒T的RT-PCR检测

通过选取河南省郑州市周边桃园生长不正常的树体叶片,进行RT-PCR检测桃病毒T的感染。结果表明,18份样品中检测到了6份样品存在病毒感染,检出率为33.3%。检出病毒的桃树样品分布在新郑市多个乡镇的果园,共有5个品种检出病毒;来自巩义市的样品未检测出桃病毒T。检出病毒的桃品种既有生产上的老品种,又有近几年栽植的新品种。结合多个桃园的病毒检出,说明病毒T已在生产中存在较长时间,并在局部区域呈扩散趋势。

登革热疾病负担及预防控制策略中国专家共识

登革热是由登革病毒感染引起的人兽共患自然疫源性疾病,主要由伊蚊叮咬传播,流行于热带和亚热带地区。目前登革热在全球快速蔓延,中国登革热疫情依然是由输入病例引起的本土传播,其发病率呈快速上升趋势,流行范围也在逐步扩大,严重危害人民群众的健康,但目前尚无有效的抗病毒药物和理想疫苗用于治疗和预防。中华医学会热带病与寄生虫学分会、中华预防医学会媒介生物学及控制分会和中国疫苗行业协会基础研究专业委员会的专家学者,在梳理全球和中国登革热的疾病负担、传统媒介生物控制以及新型防控手段最新进展的基础上,形成了本共识,旨在为相关部门更好地制定登革热防控政策提供科学依据。

几种诱抗剂对西瓜ZYMV的防治效果评价

为探索对西瓜病毒病具有防效作用的植物免疫诱抗剂,以小西葫芦黄花叶病毒(zucchini yellow mosaic virus,ZYMV)为防治对象,植株的显症率及相对防效为指标,评价了6种不同浓度的哌啶酸(Pip)、N-羟基哌啶酸(NHP)、没食子酸、苯并噻二唑(BTH)、壳寡糖、β–氨基丁酸(β-aminobutyric acid,BABA)及其2种药剂和3种药剂复配后对该病毒的防治效果。结果显示,单一药剂喷施后对西瓜ZYMV的防效从高到低依次为:NHP(0.5 mmol·L^(-1))、Pip(2 mmol·L^(-1))、壳寡糖(1 g·L^(-1))、没食子酸(0.5 g·L^(-1))、BABA(1 mmol·L^(-1))、BTH(0.1 mmol·L^(-1));复配药剂试验中,2种药剂复配防效最好的是2-Ⅶ(NHP 0.5 mmol·L^(-1)+Pip 2 mmol·L^(-1)),接种后11 d、无菌水对照植株显症率达到100.00%时,该组合处理的植株显症率为10.00%,相对防效达89.99%,但该复配药剂会影响植株生长;3种药剂复配防效较好的组合是3-Ⅰ(没食子酸0.5 g·L^(-1)+NHP 0.5 mmol·L^(-1)+BABA 1 mmol·L^(-1))和3-Ⅱ(没食子酸0.5 g·L^(-1)+NHP 0.5 mmol·L^(-1)+Pip 2 mmol·L^(-1)),显症率分别为27.27%、33.33%,相对防效分别为79.49%、68.27%,显著高于其他组合,其中3-Ⅱ处理的植株显症率增加缓慢,防病效果较其他处理持久,防治效果最优。综上,NHP、Pip和没食子酸3种诱抗剂在预防西瓜病毒病害中具有潜在的应用价值。

Expert consensus on the management process of gynecological emergency under the regular epidemic prevention and control of COVID-19

At present,China is in the stage of the COVID-19 epidemic where regular prevention and control measures are required to contain the spread of disease.Reports of new sporadic cases are still widespread across China and medical personnel remain at high risk of exposure to infection.This is especially the case for medical staff working within emergency departments.Most gynecological emergency cases are complex and a high proportion require emergency surgical treatment.By referring to national regulations and requirements on COVID-19 prevention and control,and by summarizing our experiences in the battle against COVID-19 within Wuhan,this consensus report provides recommendations on the triage,reception,consultation,admission and surgical management of gynecological emergency patients.We also make suggestions for the environmental layout and disinfection and the medical waste management.This consensus aims to optimize the diagnosis and treatment process of gynecological emergency patients and reduce the exposure risk of medical staff within the current context of routine COVID-19 prevention and control.

植物源杀菌剂大黄素甲醚对烟草病毒病的防治效果研究

新型植物源杀菌剂大黄素甲醚是从中药植物大黄中提取的天然蒽醌类化合物,具有毒性低、降解快、残留低等特点,是化学杀菌剂的理想替代产品,适用于绿色生产。为了明确大黄素甲醚对烟草病毒病的防治效果、最佳施药时期及施用量,本研究以0.1%大黄素甲醚水剂为试验药剂,以8%宁南霉素水剂和5%盐酸吗啉胍可溶粉剂为对照药剂,开展了田间小区试验。结果表明,烟草移栽定植期施用0.1%大黄素甲醚水剂对烟草病毒病的防治效果较团棵期施用好,当用药量为1 500 mL/hm^(2)时药后10 d的防治效果可达到62.81%。