Ebola virus disease: a zoonotic disease with an extremely high fatality rate / 中国热带医学

@# Ebola virus disease (EVD) is a severe infectious disease caused by Ebola virus in humans and primates. The main clinical features are fever and bleeding. The disease was first identified in Zaire and Sudan in Africa in 1976. Since then, it has caused many large-scale epidemics in Africa. One of the largest and most complex Ebola outbreaks in history was the 2014-2016 outbreak in West Africa, which caused more cases and deaths than all previous outbreaks combined. As of 2022, about 35 000 EVD cases and 15 000 deaths have been reported. During the African pandemic, EVD also spread to other regions outside the African continent, such as the Americas and Europe, and became a public health issue of worldwide concern. In Africa, the re-emergence of the disease in Uganda and the Republic of Congo in 2022 has attracted much attention from the world. This article systematically summarizes the history, epidemiological distribution, route of infection, clinical symptoms, diagnosis, treatment, prevention and control of Ebola virus disease, so as to provide reference for relevant workers in China.

Expert consensus on neurosurgical department during the prevention and control of coronavirus disease 2019 / 解放军医学杂志

In 2019, coronavirus disease 2019 (COVID-19) broke out in China. The strictest prevention and control measures had been performed because of its high infectivity and mortality rate. Although the number of confirmed cases has decreased, it has not been eliminated. Neurosurgical doctors and nurses are facing the dual pressure resulting from the prevention and control of neurosurgical disease and novel coronavirus infection. Faced with the severe situation, we should standardize the methods of medical treatment and nursing process, so as to reduce the incidence of nosocomial infection among patients and their families in the hospital, and the occupational exposure of medical workers. We wrote the consensus in conjunction with Neural Intensive Nursing and Rehabilitation Group and Cerebral Protection in Cardiac Intensive Care Group, which is belonging to Neural Regeneration and Repair Committee of Chinese Association of Research Hospitals, and also including Nursing and Rehabilitation Group, which is belonging to Health Management Professional Committee Cell Biology Society of Liaoning Province. We referred to domestic and foreign research results and threw out suggestions for patient's receiving, prevention and control guidance, perioperative nursing, ward disinfection to provide reference for neurosurgical personnel, patients and their families.

A Reverse-transcription Recombinase-aided Amplification Assay for the Rapid Detection of the Far-Eastern Subtype of Tick-borne Encephalitis Virus / 生物医学与环境科学（英文）

OBJECTIVE@#Tick-borne encephalitis virus (TBEV) is an emerging pathogen in Europe and North Asia that causes tick-borne encephalitis (TBE). A simple, rapid method for detecting TBEV RNA is needed to control this disease.@*METHODS@#A reverse-transcription recombinase-aided amplification (RT-RAA) assay was developed. This assay can be completed in one closed tube at 39 °C within 30 minutes. The sensitivity and specificity of RT-RAA were validated using non-infectious synthetic RNA representing a fragment of the NS5 region of the wild-type (WT) TBEV genome and the Senzhang strain. Additionally, 10 batches of tick samples were used to evaluate the performance of the RT-RAA assay.@*RESULTS@#The analytical limit of detection of the assay was 20 copies per reaction of the TBEV synthetic transcript and 3 plaque-forming units (pfu) per reaction of TBEV titers. With the specific assay, no signal due to other arboviruses was observed. Of the 10 batches of tick samples obtained from the Changbai Mountains of China, three were TBEV-positive, which was consistent with the results of the quantitative real-time PCR assay.@*CONCLUSION@#A rapid, highly sensitive, specific, and easy-to-use method was developed for the detection of the TBEV Far-Eastern subtype.

Serological Survey of Zika Virus in Humans and Animals in Dejiang Prefecture, Guizhou Province, China / 生物医学与环境科学（英文）

OBJECTIVE@#The current outbreak of Zika virus (ZIKV) poses a severe threat to human health. Two ZIKV strains were isolated from mosquitoes collected from the Dejiang prefecture in China in 2016, which was the first isolation of ZIKV in nature in China.@*METHODS@#In this study, serum samples were collected from 366 healthy individuals and 104 animals from Dejiang prefecture in 2017, and the plaque reduction neutralization test (PRNT) was used to evaluate the seroprevalence of ZIKV.@*RESULTS@#None of the 366 residents from whom the samples were collected were seropositive for ZIKV. None of the 11 pigs from whom the samples were collected were seropositive for ZIKV, while 1 of 63 (1.59%) chickens and 2 of 30 (6.67%) sheep were seropositive for ZIKV.@*CONCLUSION@#The extremely low seropositivity rate of ZIKV antibodies in animals in the Dejiang prefecture, Guizhou province in this study indicates that ZIKV can infect animals; however, there is a low risk of ZIKV circulating in the local population.

TaqMan Real-time RT-PCR Assay for Detecting and Differentiating Japanese Encephalitis Virus / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To detect Japanese encephalitis virus (JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction (RT-PCR) detection system was developed.</p><p><b>METHODS</b>By aligning the full-length sequences of JEV (G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay.</p><p><b>RESULTS</b>With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/µL. The coefficients of variation of this real-time RT-PCR were all < 2.8%. The amplification efficiency of this method was between 90% and 103%.</p><p><b>CONCLUSION</b>A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.</p>

The Relationship between Japanese Encephalitis and Environmental Factors in China Explored Using National Surveillance Data / 生物医学与环境科学（英文）

Japanese encephalitis (JE) is a serious public health issue. This study was undertaken to better understand the relationship between JE distribution and environmental factors in China. JE data from 2005 to 2010 were retrieved from National Notifiable Disease Report System. ArcGIS, remote sensing techniques, and R software was used to exhibit and explore the relationship between JE distribution and environmental factors. Our results indicated that JE cases were mostly concentrated in warm-temperate, semitropical and tropical zones with annual precipitation > 400 mm; Broad-leaved evergreen forest, shrubs, paddy field, irrigated land, dryland, evergreen coniferous forest, and shrubland were risk factors for JE occurrence, and the former five were risk factors for counties with high JE incidence. These findings will inform the effective allocation of limited health resources such as intensive vaccination, surveillance and training in areas with high environmental risk factors.

A Centralized Report on Pediatric Japanese Encephalitis Cases from Beijing Children's Hospital, 2013 / 生物医学与环境科学（英文）

Fifteen pediatric cases of suspected Japanese encephalitis (JE) were reported in Beijing Children's Hospital during the late summer of 2013. The clinical manifestations in most cases included high fever, seizures, and abnormal magnetic resonance imaging findings. Twelve of 15 cases were laboratory-confirmed as JE cases by pathogen identification. Epidemiological investigations showed that five of the 12 laboratory-confirmed patients had an incomplete JE vaccination history. Follow-up investigations after discharge indicated that seven laboratory-confirmed JE patients without JE vaccinations had relatively poor prognoses, with an average Modified Rankin Scale (MRS) score of 2.6 when compared with the other five laboratory-confirmed, JE-vaccinated patients with an average MRS score of 0.5. The observation of pediatric JE cases among those with a history of JE vaccination warrants further attention.

Real-time RT-PCR Assay for the detection of Tahyna Virus / 生物医学与环境科学（英文）

A real-time RT-PCR (RT-qPCR) assay for the detection of Tahyna virus was developed to monitor Tahyna virus infection in field-collected vector mosquito samples. The targets selected for the assay were S segment sequences encoding the nucleocapsid protein from the Tahyna virus. Primers and probes were selected in conserved regions by aligning genetic sequences from various Tahyna virus strains available from GenBank. The sensitivity of the RT-qPCR approach was compared to that of a standard plaque assay in BHK cells. RT-qPCR assay can detect 4.8 PFU of titrated Tahyna virus. Assay specificities were determined by testing a battery of arboviruses, including representative strains of Tahyna virus and other arthropod-borne viruses from China. Seven strains of Tahyna virus were confirmed as positive; the other seven species of arboviruses could not be detected by RT-qPCR. Additionally, the assay was used to detect Tahyna viral RNA in pooled mosquito samples. The RT-qPCR assay detected Tahyna virus in a sensitive, specific, and rapid manner; these findings support the use of the assay in viral surveillance.

First isolation of quang binh-like virus from mosquitoes in China / 病毒学报

This study aims to investigate the distribution patterns of mosquito-borne viruses in Menghai County, Xishuangbanna Prefecture, Yunnan Province, China and to provide evidence for the prevention and control of mosquito-borne diseases. Mosquito samples were collected using mosquito lamps. Viruses were isolated from the samples by cell culture, and the isolates were identified by RT-PCR. The genomes of isolates were sequenced for phylogenetic analysis. In July 2012, a total of 1468 mosquitoes were captured in Daluo Town of Menghai County; they were divided into 32 pools, including Culex tritaeniorhynchus (28 pools, 1383 mosquitoes), Culex quinquefasciatus (2 pools, 66 mosquitoes), and Anopheles (2 pools, 19 mosquitoes). Golden hamster kidney cells (BHK-21) and Aedes albopictus cells (C6/36) were used for virus isolation. The results showed that C6/36 cells were susceptible to two isolates recovered from Culex tritaeniorhynchus (BNDL1205 and BNDL1227), with marked cytopathic effect (CPE) of cell fusion. By contrast, the two isolates could not cause CPE in BHK-21 cells. RT-PCR was performed for the two isolates using the flavivirus-specific primers FU2/cFD3, and a 800-bp amplicon was obtained from both of them. Phylogenetic analysis showed that the two isolates shared the same evolutionary branch with the Quang Binh virus (QBV) strain VN180, which had been isolated from Vietnam, with nucleotide sequence homologies of 83.4% and 82.9%, respectively. However, there existed relatively large differences in nucleotide sequence between them and other Culex flavivirus strains previously isolated in China and other regions. In light of the similarity between the two isolates and QBV, BNDL1205 and BNDL122 were referred to as Quang Binh-like virus, which were first reported in China.

Study on the B cell linear epitopes of rabies virus CVS-11 nucleoprotein / 病毒学报

To study the B cell linear epitopes of rabies virus CVS-11 nucleoprotein, peptides were synthesized according to the amino acid sequences of B cell linear epitopes. Linear epitopes predicted by bioinformatics analysis were evaluated with immunological techniques. Indirect enzyme-linked immunosorbent assay showed that titers of antibodies to peptides (355-369 and 385-400 residues of rabies virus CVS-11 nucleoprotein) were above 1:12 800 in mouse sera. The antibodies recognized denatured rabies virus CVS-11 nucleoprotein in Western blot analysis. Purified anti-peptide antibodies recognized natural rabies virus CVS-11 nucleoprotein in BHK-21 cells in indirect fluorescent antibody test. The 355-369 and 385-400 residues of rabies virus CVS-11 nucleoprotein were validated as B cell linear epitopes.

Molecular characterization of full-length genome of Japanese encephalitis virus genotype V isolated from Tibet, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To determine the molecular characterization of full-length genome of Japanese encephalitis virus (JEV) genotype V.</p><p><b>METHODS</b>The full-length nucleotide sequences of JEV strains isolated from different locations and sources were used in sequence and phylogenetic analysis.</p><p><b>RESULTS</b>The full-length genome of genotypes V JEV, XZ0934, and Muar strain were composed of 10 983 and 10 988 nucleotides respectively and shared a lower level of identity with JEV genotypes I-IV, ranging from 78.4% (G I, KV1899) to 79.7% (G III, JaGAr01), for the nucleotide sequences, and from 90.0% (G I, KV1899) to 91.8% (G III, JaGAr01) for the amino acid sequences. The open reading frame (ORF) of JEV genotype V spanned nucleotides 96 to 10 397 and encoded 3 433 amino acids. Interestingly, a comparison with JEV genotype I-IV revealed that 3 nucleotides (encoded with a serine residue) were inserted in the NS4A gene of JEV genotype V, and the insertion of nucleotides was also found in downstream of the ORF stop codon in 3'-untranslated region. Moreover, numerous amino acid mutations were observed in 3 functional domains of the E gene of JEV genotype V.</p><p><b>CONCLUSION</b>The molecular characterization of JEV genotype V is significantly different from that of the known genotypes I-IV. The mutations located in the coding region and the non-coding region may be molecular markers of JEV genotype V and warrant further studies to determine their effects on biology and immunogenicity of genotype V strains.</p>

Factors influencing the number of rabies cases in children in China / 生物医学与环境科学（英文）

To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive analysis was carried on the prevalence and related factors. The results showed that the rabies cases in children accounted for 21.3% of the total number of rabies cases in China, 97.0% of these cases occurred in rural areas, they were mainly caused by dogs (81.5%), and were primarily level III exposure (47.7%). More than half of the cases were not treated with wound care, vaccination rate was extremely low (15.7%), and only 5.9% of cases were injected with antibodies. Furthermore, 25.4% of cases adopted incorrect treatments such as extruding bleed and wound closure, cases vaccinated with 5 injections accounted for only 22.5%. In conclusion, the prevalence of rabies cases in children in China remains a serious concern, the number and immune status of dogs in rural areas, and knowledge of rabies by risk populations should be considered in future rabies prevention and control programs.

Comparative analysis of the pathogenic mechanisms of street rabies virus strains with different virulence levels / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To characterize two strains of street rabies virus (RABV) isolated from the brain tissue of cattle from Inner Mongolia. Differences in the histopathological and ultrastructural changes in the brain tissue of infected mice were determined to reveal variation in the pathogenesis of infection between street rabies virus strains.</p><p><b>METHODS</b>Ten-day-old mice were intracranially inoculated with one of three virus strains and brain tissue harvested when the mice were moribund. Various histopathological and ultrastructural markers of disease were then compared between the groups.</p><p><b>RESULTS</b>Infection with the street virus strain CNM1101C resulted in severe neuronal dendrites damage, but only mild cell apoptosis, T lymphocyte infiltration and microglial activation. Infection with the other street virus strain, CNM1103C, was characterized by cell apoptosis, T lymphocyte infiltration and microglial activation as well as dendrites damage. However, in comparison, infection with the attenuated virus strain CTN caused severe T lymphocyte infiltration, microglial activation and cell apoptosis, but left the neuronal dendrites intact.</p><p><b>CONCLUSION</b>The two street rabies virus strains isolated from cattle from Inner Mongolia had different levels of virulence and caused distinct pathological changes in infected mice. Therefore, we concluded that different pathogenic mechanisms exist between different RABV strains.</p>

Identification of animal rabies in Inner Mongolia and analysis of the etiologic characteristics / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2011, and analyze their etiological characteristics.</p><p><b>METHODS</b>Pathological observation was conducted on the brain specimens of three infected animals with Hematoxylin-Eosin staining, followed by confirmation using immunofluorescence and nested RT-PCR methods. Finally, phylogenetic analysis was conducted using the virus N gene sequence amplified from three specimens.</p><p><b>RESULTS</b>Eosinophilic and cytoplasmic inclusion bodies were seen in neuronal cells of the CNS; and rabies non-characteristic histopathological changes were also detected in the CNS. The three brain specimens were detected positive. N gene nucleotide sequence of these three isolates showed distinct sequence identity, therefore they fell into different groups in the phylogenetic analysis. N gene in the cow and dog had higher homology with that in Hebei isolate, but that in the beef cattle had higher homology with that in Mongolian lupine isolate and Russian red fox isolate.</p><p><b>CONCLUSION</b>Rabies were observed in the dairy cow, beef cattle and canine in the farm in Inner Mongolia, in 2011, which led to a different etiologic characteristics of the epidemic situation.</p>

Pathogenicity of rabies viruses isolated in China: two fixed strains and a street strain / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the virulence characteristics of two fixed strains (CTN and aG) and a street strain (HN10) of rabies viruses isolated in China.</p><p><b>METHODS</b>ICR mice of different age groups were inoculated with CTN, aG and HN10 rabies virus strains via the intracracerebral (i.c.) or intramuscular (i.m.) routes, and observed for 20 days.</p><p><b>RESULTS</b>The CTN strain was pathogenic to 7-day-old suckling mice that received i.c. inoculations and 3-day-old suckling mice that received i.m. inoculations. The aG strain was pathogenic to 4-week-old mice that received i.c. inoculations and 7-day-old suckling mice that received i.m. inoculations. The HN10 strain was pathogenic to mice of all age groups via both inoculation routes. In moribund mice, the viruses had spread to most regions of the brain. The CTN and HN10 strains had similar dissemination patterns in the brain; both viral antigens could be found in the dentate gyrus (DG), whereas few viral antigens were present in the DG from specimens that had been infected with the aG strain.</p><p><b>CONCLUSION</b>A comprehensive sequence analysis of the G protein suggested that differences in gene sequences may be responsible for producing strain-specific differences in pathogenicity and distribution in the brain.</p>

An outbreak of imported dengue fever from Myanmar to the border of China, with its viral molecular epidemiological features / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the epidemiologic characteristics of dengue fever, imported from Myanmar to the border of Yunnan province, China. Viral molecular epidemiologic features were also studied.</p><p><b>METHODS</b>Questionnaires were used on each diagnosed, suspected dengue fever, case or unknown cases with fever when coming from Myanmar entering the port and hospitals in Ruili city of Yunnan province. Serum samples of these patients were collected to detect IgM antibody against dengue virus and RT-PCR assay. Homology and phylogenetic tree based on the whole nucleotide sequence of PrM-C and NS5 gene of dengue virus were further analyzed.</p><p><b>RESULTS</b>A total of 103 sera were collected from patients at acute stage in Ruili city in July to November 2008. Among them, 49 cases were confirmed for dengue fever according to IgM and nucleic acid testings. Except one, other 48 cases were all imported into Ruili, from Myanmar. Of those, 18 patients were residents from Mujie city of Myanmar and hospitalized in Ruili and the rest 30 patients were Chinese citizens who had finished business and returned from Myanmar. Two isolates of serum samples from the imported cases were identified and both homology and phylogenetic analysis were performed, using the nucleotide sequences of PrM and NS5 genes. They were divided into dengue type 1 (RLB61) and dengue type 3 (RLC31) and were closer to the dengue virus strains isolated from Southeast Asia countries.</p><p><b>CONCLUSION</b>It is confirmed that an epidemic of dengue fever which was imported from Myanmar to Ruili city of Yunnan province, China. Evidence also showed that both type I and III epidemic strains of dengue virus did exist in Mujie city of Myanmar in 2008.</p>

Evolutionary and transmission characteristics of rabies viruses in Asia / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the rabies virus (RABV) evolutionary relationship between the strains of China and Asia and to know the evolution and transmission characteristics of RABV in Asia.</p><p><b>METHODS</b>The G sequences of representative strains from China were selected and combined the sequences of other countries in Asia to analyze using BEAST and MigraPhyla software.</p><p><b>RESULTS</b>The phylogenetic analysis showed that six groups (China I-VI) of China had different epidemic range: China I , II and V groups just cycled in our country; China VI group, from Guangxi and Yunnan provinces, crossed with Southeast Asian strains; China III group and IV group also have closer genetic relationship with Asian country strains.</p><p><b>CONCLUSION</b>Geographic migration in Asia showed that Thailand and India may be two rabies transmission centers in Asia.</p>

Construction and characterization of EGFP reporter gene labeled Sindbis virus / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To construct and characterize EGFP reporter gene labeled Sindbis virus (SINV).</p><p><b>METHODS</b>The reporter gene EGFP was inserted into the genome of infectious clone pBR-XJ160 by using multi-fusion long fragment PCR method. Then apply reverse genetic manipulation technique to rescue and obtain EGFP labeled SINV.</p><p><b>RESULTS</b>We successively obtained labeled SINV, which has good fluorescent expression characteristics and genetic stability.</p><p><b>CONCLUSION</b>The labeled virus can be seen in living cells and living body, and this serves as a good tool for cell and tissue tropism and biological function study of viruses. This study laid a foundation for further studying the cell tropism, biological functions and infection mechanism of SINV.</p>

Synthesis and immunosuppressive effects of novel phthalazine ketone derivatives / 药学学报

A series of phthalazine ketone compounds were synthesized and the structures were confirmed by H NMR and HR-MS spectrum. All target compounds were obtained through 7 steps, including selective reduction, nitration, bromination, ring enlargement, reduction, Knoevenagel and acylated reaction. The compounds were evaluated for their immunosuppressive effects of T-cell proliferation and inhibitory activity of IMPDH type II in vitro, as well as their structure-activity relationship were assessed. Several compounds exhibited strong immunosuppressive properties, especially compounds 7f and 7h, with IC50 values of 0.093 micromol x L(-1) and 0.14 micromol x L(-1) respectively, which were superior to mycophenolic acid. The information obtained from the studies may be useful for further research on the immunosuppressive agents.

Current status of canine rabies in China / 生物医学与环境科学（英文）

The number of human rabies cases acquired from dog bites constitutes a high proportion of the total rabies cases in China, although the number of human rabies cases has gradually decreased in recent years. The pivotal role of dogs in the spread of rabies indicates that controlling and preventing canine rabies could be a key step in eradicating human rabies in China. The primary aims of this review are to discuss the properties and pathogenesis of the rabies virus, the clinical signs and diagnosis of canine rabies, threshold host density and vaccination of dogs, and the prevention and control of canine rabies in China.