ABSTRACT
Dengue is the most prevalent and rapidly spreading mosquito-borne viral disease.As a dengue non-endemic country,China has experienced several dengue outbreaks in recent years.However,dengue patients in China displayed distinct clinical characteristics compared to patients in endemic countries.To standardize the diagnosis and treatment of dengue fever,the experts of the Society of Infectious Diseases,Society of Tropical Medicine and Parasitology of Chinese Medical Association,and the Society of Emergency Medicine,China Association of Chinese Medicine have reached this guideline based on guidelines for diagnosis,treatment,prevention and control of dengue (World Health Organization,2009);guidelines for diagnosis and treatment of dengue (National Health and Family Planning Commission of the People's Republic of China,2014,Edition 2),health industry standard of the People's Republic of China "diagnosis for dengue fever (WS216-2018)" and systemic reports on dengue.The guideline includes 8 aspects:introduction,terminology,epidemiology and prevention,etiology and pathogenesis,clinical features,diagnosis,treatment and problems to be solved.
ABSTRACT
Objective To prepare quality control samples for St.Louis encephalitis virus(SLEV)molecular detection by constructing pseudovirus containing target sequences of SLEV.Methods According to the principles of armored RNA technique, the prM gene sequence of SLEV was cloned into the prokaryotic expression vector to generate recombinant plasmid pSE380-MS2-SLEV.Then, recombinant E.coli transformed with the corresponding plasmid was induced with IPTG to produce recombinant pseudovirus particles.The particles were purified by chloroform and further characterized by double enzyme digestion and transmission electron microscopy.The temperature sensitivity experiments and quantitative RT-PCR were performed to validate the potential of these pseudovirus particles as quality control samples.Results PCR amplification and sequencing analysis confirmed that the prM gene sequence of SLEV was cloned into vector pSE380-MS2.Transmission electron microscopy showed that homogenous spherical particles with a diameter of about 25 nm were produced upon IPTG induction.The SLEV genomic RNA within the pseudovirus particles was resistant to DNaseⅠand RNase A digestion, and remained stable for 20 days at 37℃.These samples were validated with quantitative RT-PCR for SLEV.Conclusion The RNase-resistant and stable pseudovirus particles containing prM fragment of SLEV are constructed successfully, which can be used as positive quality control samples for RNA extraction and molecular detection.
ABSTRACT
Enterovirus 71 (EV71) is one of the primary causative agents of hand, foot and mouth disease in children and closely associated with severe neurological complications and even deaths.EV71 outbreaks have occurred throughout the Asia-Pacific region since 1990s, posing global public health threat;however, no specific therapeutic strategy exists for severe EV71 infection.Several inactivated vaccine products have entered or finished the clinical trial stage, and some novel vaccine candidates, including live attenuated, subunit, and virus-like particle, show great potential for further develop-ment.This review summarizes the present situation and progress in the development of EV71 vaccines.
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Vaccine immunization represents the most effective strategy against viral infections .Antiviral vaccine candi-dates currently include live attenuated vaccine , inactivated vaccine , DNA vaccine and genetic engineering vaccine .Live at-tenuated vaccines , eliciting efficient humoral and cellular immune response by simulating natural virus infection , are clini-cally widely used.Traditionally, live attenuated vaccine strains are obtained by serial passaging in vitro or in vivo, a costly procedure accumulating random mutations .microRNA( miRNA)-targeting host gene regulation exhibits high species and tis-sue specificity .Introducing certain miRNA target sequence into viral genome by reverse genetic technique can effectively attenuate virus strains, which has great potential in vaccine design and development .In this article,attenuation strategies and progress in its application in vaccine research are disscussed .
ABSTRACT
Influenza, caused by influenza virus, is a serious respiratory illness which poses a global public health threat. Vaccination is the primary strategy for the prevention and control of influenza. Although both inactivated vaccines and the live attenuated vaccines are effective in preventing influenza, the current vaccines have poor efficacy in the elderly and fail to provide protection against heterosubtype viruses. Development of a safer and more effective influenza vaccine that provides broad cross protection, overcoming the intrinsic limitation of the current vaccines, has been a scientific challenge. During the past decades, structural biology, reverse genetic and other virological technologies developed quickly and sped the progress of influenza vaccinology. Some new strategies for developing influenza vaccine have been generated, produced encouraging results, which showed great prospect as next-generation of influenza vaccines.
Subject(s)
Humans , Disease Outbreaks , Hemagglutinin Glycoproteins, Influenza Virus , Allergy and Immunology , Influenza Vaccines , Allergy and Immunology , Influenza, Human , Allergy and Immunology , Virology , Orthomyxoviridae , Allergy and Immunology , Vaccines, Attenuated , Allergy and Immunology , Vaccines, Inactivated , Allergy and ImmunologyABSTRACT
Viral replicon is a kind of self-replicating viral RNA sourced from viral genome, which contains viral non-structural genes that are critical for viral genome replication with structural proteins deleted or replaced by foreign genes. Kunjin virus is a member of the Flavivirida family, Flavivirus genus, and Kunjin virus replicon is the first and the clearly defined flavivirus replicon. Kunjun virus replicon has been regarded as an excellent viral vector on account of its high expression, lower cytotoxicity and genetic stability. These unique characteristics of kunjin virus replicons make them suitable for the study of viral genome replication, recombinant proteins production, vaccine development and gene therapy. In this article, recent progress in the development, properties and applications of kunjin virus replicon system was briefly reviewed.
Subject(s)
Genetic Vectors , Genetics , Genome, Viral , Recombination, Genetic , Replicon , Genetics , Virus Replication , Physiology , West Nile virus , Genetics , MetabolismABSTRACT
Hand-foot-mouth disease (HFMD) is an acute infectious disease caused by various enteroviruses. Recently, large HFMD outbreaks caused by enterovirus type 71 (EV71) have been frequently reported in China, posing great threats on children's health. There is no specific antiviral therapy for severe HFMD, and patient management mainly depends on supportive and symptomatic treatment. Intravenous immunoglobulin (IVIG) is a pharmaceutical preparation of human IgG that is pooled from thousands of healthy blood donors, and contained neutralization antibodies against various enteroviruses, including EV71. IVIG therapy should be carefully administrated for severe HFMD considering its role on passive immunization against EV71 and immune regulation.