As an inevitable trend of social development, aging has generated a wide and far-reaching impact on every aspect of society, especially posing severe challenges for the heath system of all countries and regions around the world. Facing the objective reality of humans co-existing with diseases in a long term and people’s ever-growing demand for healthcare, the successful development of vaccine products can provide people with effective preventive measures to combat infectious diseases. This article summarizes the development and use of 4 vaccines that are suitable for the elder population, i.e., influenza vaccine, pneumococcal vaccine, varicella-zoster virus vaccine and respiratory syncytial virus vaccine, aiming to provide some reference for the development and popularization of these vaccines and to improve the well-being of the senior citizens.

Abstract: The emerging infectious diseases have become an important risk factor affecting human public health. Vaccination remains the most critical approach to the prevention and control of such diseases. Since the outbreak of the COVID-19 epidemic, lots of transformational basic innovative vaccine technologies and strategies have been developed. The third-generation vaccine technology represented by mRNA vaccine has gradually become a new approach to the research and development of vaccines. This paper introduces the characteristics of different vaccine technologies in recent years, and summarizes the latest research progress in current vaccine products based on different platforms, so as to provide experience and reference for future research and development of vaccines.

Objective To explore the association between iron metabolism indexes and the risk of gestational diabetes mellitus(GDM)in pregnant women with advanced age.Methods A total of 292 pregnant women,whose age were≥35 years old and gave birth in Taicang First People's Hospital from April 2021 to April 2023,were retrospectively included and divided into GDM group and non-GDM group.The differences of iron metabolism indexes[serum ferritin(SF),serum iron(SI)and hemoglobin(Hb)]measured from the 20 to 24 weeks of gestation were compared between the two groups.Multivariable Logistic regression model was used to explore the association of SF,SI and Hb with GDM.Based on the data of single nucleotide polymorphism from IEU OpenGWAS(http://gwas.mr-cieu.ac.uk/)and FinnGen datasets,two samples Mendelian randomization analysis were conducted to explore the causal relationship between iron metabolism indexes and GDM by using the methods of Inverse Variance Weighted(IVW).Results In the maximally ad-justed multi-factor logistic models,the statistically significant association between SF measured from 20 to 24 weeks of gestation and the risk of GDM was found[odds ratio(95％confident interval)=1.02(1.01-1.04),P=0.001].The association between Hb and GDM was marginally significant[odds ratio(95％confident interval)=1.04(1.00-1.07),P=0.044],but no association between SI and GDM reached statistical significance.However,Mendelian randomization analysis showed there was no significant evidence for causal association between SF,Hb and GDM.Conclusion SF examined at 20 to 24 weeks of gestation could be used as a biomarker of GDM in the pregnant women with advanced age,but no evidence supported the causal association between SF and GDM.

The COVID-19 epidemic that occurred at the end of 2019 spreads rapidly to all parts of the world, putting the global public health system to a severe test. With the continuation of the epidemic, SARS-CoV-2 variants are constantly emerging. In particular, the mutation of the spike protein can cause changes in the infectivity and antigenicity of the virus, resulting in an increase in the infectivity and a decline in the protective efficacy of existing vaccines, and even the replacement of epidemic strains. This is also one of the reasons why the epidemic has not been effectively controlled so far. Nowadays, the main circulating variants have changed their characteristics to a certain extent, and the neutralization sensitivity of some variants to neutralizing monoclonal antibodies, immune sera and convalescent sera has decreased to a certain extent compared with the original strains. The emergence of variants is not only related to the characteristics of the virus itself, but also to the changes of transmission host and the chronic infection in people with deficient immunity. The emerging variants should be closely monitored, and their functional characteristics should be systematically studied so as to provide data for vaccine research and development and the designation of immunization strategies.

In 2009, hepatitis E virus was first detected in wild rats ( Rattus norvegicus) in Germany and was designated as rat hepatitis E virus (rat HEV). Since then, rat HEV has been detected in various murine rodents in many geographic regions. The potential of rat HEV to infect human has been ignored as the viral genomic nucleotide sequences of rat HEV and the HEV strains of human sources are only about 50%-56% identical. Recently, a few clinical hepatitis E cases with chronic or acute rat HEV infection have been reported and raised many concerns. Here, advances in studies of the prevalence of rat HEV in animals and the clinical hepatitis E cases caused by rat HEV were reviewed.

Influenza virus has a continuous and extensive impact on human health around the world. Its extensive animal host characteristics and highly variable characteristics lead to continuous antigen drift and change of susceptible populations, causing repeated global influenza epidemics, and also affecting the protective effect of seasonal influenza vaccine. This research in a number of subtypes of influenza a virus, for example, from the antigenic drift of antigenicity, influence of the seasonal influenza vaccine strains and popular strain compatibility, broad-spectrum flu vaccine development train of thought, etc. summarizes the progress of relevant research, to deepen the understanding of the influenza virus antigenic evolution, provide reference for flu vaccine development in the future.

Influenza virus has a continuous and extensive impact on human health around the world. Its extensive animal host characteristics and highly variable characteristics lead to continuous antigen drift and change of susceptible populations, causing repeated global influenza epidemics, and also affecting the protective effect of seasonal influenza vaccine. This research in a number of subtypes of influenza a virus, for example, from the antigenic drift of antigenicity, influence of the seasonal influenza vaccine strains and popular strain compatibility, broad-spectrum flu vaccine development train of thought, etc. summarizes the progress of relevant research, to deepen the understanding of the influenza virus antigenic evolution, provide reference for flu vaccine development in the future.

Metagenomic next-generation sequencing (mNGS) could be used for pathogen detection from nearly all types of clinical samples. Especially, the unique diagnostic capability of pathogen mNGS detecting unknown causative agent of infectious diseases makes this method become an importation complement and irreplaceable component for conventional routine laboratory test. However, the complexity of the testing process, the rapid product update, and the insufficiency in quality control and evaluation methods that all make clinical transformation, industry development, and regulation of this technology full of challenge and uncertainty. This review briefly introduces the technical advantages and challenges, and describes the general workflow and quality control steps in details. Finally, it focuses on current considerations regarding quality evaluation methods and standards for pathogen mNGS.
Communicable Diseases ; High-Throughput Nucleotide Sequencing ; Humans ; Metagenome ; Metagenomics ; Quality Control

Antibody dependent enhancement (ADE) is a common phenomenon in virology. It is involved in the mechanisms of infections caused by Dengue virus (DV), severe acute respiratory syndrome coronavirus (SARS-CoV), influenza virus, HIV and other viruses and affects the research and development of vaccines against them. Because the pre-existing specific antibodies or antibodies at sub-neutralizing titer can enhance the infectivity of viruses, leading to disease aggravation, vaccination may promote infection instead of preventing it. This article focused on the impact of ADE on the research and development of vaccines and the assessment of ADE.

Objective:To analyze the neutralization properties of different genotypes and mutants of severe fever with thrombocytopenia syndrome virus (SFTSV).Methods:Pseudoviruses of SFTSV of different genotypes and mutants were constructed using VSVΔG-Fluc*G backbone. Neutralization assays were established based on the pseudoviruses. DNA vaccines for different SFTSV genotypes were prepared. Serum samples were collected from guinea pigs immunized with the DNA vaccines. Neutralizing antibodies in serum samples from immunized guinea pigs and naturally infected patients were detected using neutralization assays and analyzed.Results:The pseudoviruses of five genotypes and 43 mutants were successfully constructed and the neutralization assays based the pseudoviruses were successfully established after optimizing the reaction parameters. The dilution multiple corresponding to the inhibition rate of neutralizing antibody to half of the pseudovirus infection was taken as the titer of neutralizing antibody by the reduction in pseudovirus reporter gene. The neutralization antibody titers in naturally infected patients and immunized guinea pigs were respectively in the ranges of 1∶100-1∶43 000 and 1∶100-1∶2 500 when detected with the reference HB29 pseudovirus. The neutralization antibody titers ranged from 1∶100-1∶2 500 after immunization with different genotypes of DNA vaccines. No significant statistical difference in neutralization antibody titer was observed among different genotypes or mutant strains.Conclusions:The neutralization properties of different genotypes and mutants showed no significant change, which would be very useful for developing vaccines.