RNA structures are essential for understanding their biological functions and developing RNA-targeted therapeutics. However, accurate RNA structure prediction from sequence remains a crucial challenge. We introduce DRfold2, a deep learning framework that integrates a novel pre-trained RNA Composite Language Model (RCLM) with a denoising structure module for end-to-end RNA structure prediction. DRfold2 achieves superior performance in both global topology and secondary structure predictions over other state-of-the-art approaches across multiple benchmark tests. Detailed analyses reveal that the improvements primarily stem from the RCLM's ability to capture co-evolutionary pattern and the effective denoising process, leading to a more than 100% increase in contact prediction precision compared to existing methods. Furthermore, DRfold2 demonstrates high complementarity with AlphaFold3, achieving statistically significant accuracy gains when integrated into our optimization framework. By uniquely combining composite language modeling, denoise-based end-to-end learning, and deep learning-guided post-optimization, DRfold2 establishes a distinct direction for advancing ab initio RNA structure prediction. ### Competing Interest Statement The authors have declared no competing interest.

In the original publication [...].

Background: Influenza viruses are major pathogens responsible for respiratory infections and pose significant risks to densely populated urban areas. RT-qPCR has made substantial contributions in controlling virus transmission during previous COVID-19 epidemics, but it faces challenges in terms of detection time for large sample sizes and susceptibility to nucleic acid contamination. Methods: Our study designed loop-mediated isothermal amplification primers for three common influenza viruses: A/H3N2, A/H1N1, and B/Victoria, and utilized a 4-channel microfluidic chip to achieve simultaneous detection. The chip initiates amplification by centrifugation and allows testing of up to eight samples at a time. Results: By creating a closed amplification system in the microfluidic chip, aerosol-induced nucleic acid contamination can be prevented through physically isolating the reaction from the operating environment. The chip can specifically detect A/H1N1, A/H3N2, and B/Victoria and has no signal for other common respiratory viruses. The testing process can be completed within 1 h and can be sensitive to viral RNA at concentrations as low as 10−3 ng/μL for A/H1N1 and A/H3N2 and 10−1 ng/μL for B/Victori. A total of 296 virus swab samples were further analyzed using the microfluidic chip method and compared with the classical qPCR method, which resulted in high consistency. Conclusions: Our chip enables faster detection of influenza virus and avoids nucleic acid contamination, which is beneficial for POCT establishment and has lower requirements for the operating environment.

Seasonal influenza A virus subtype H3N2 (A/H3N2) circulates globally and has been linked to higher hospitalization rates and summer outbreaks in temperate regions. Here, A/H3N2 circulation in Shanghai, China was systematically studied using data and materials generated by the Shanghai influenza surveillance network from 2005 to 2023. Time-series analysis of incidence and subtyping data showed that A/H3N2 co-circulated with other (sub)types and dominated in multiple seasonal influenza peaks, preferentially in summer. Whole genomes of 528 representative strains were sequenced, and spatiotemporal phylodynamic analysis using these and GISAID-archived sequences demonstrated that in the years before the COVID-19 pandemic, phylogenetically similar strains were circulating locally and elsewhere. However, clade 1a.1 (within 3C.2a.1b.2a), circulated in and only in Shanghai and domestically in 2022, while the sibling clade 2 predominated in other regions. Interestingly, clade 1a.1 was swiftly and completely replaced by clade 2, mostly 2a.3a.1, at the start of 2023. In hemagglutination inhibition and neutralization assays, sera from healthy donors collected in 2022 displayed higher or similar reactivity against 2a.3a.1 compared to 1a.1. By contrast, transcription and replication competence of 2a.3a.1 in MDCK cells was higher than 1a.1. These results indicated that instead of antigenicity differences enabling evasion of pre-existing immunity, higher replicative capability more likely contributed to 2a.3a.1 viruses achieving dominance in China. In addition to summarizing patterns of A/H3N2 local circulation in Shanghai, this work revealed an unusual episode in A/H3N2 global circulation and evolution dynamics in connection to the COVID-19 pandemic and explored possible mechanistic explanations.

Campylobacter species are zoonotic pathogens, as well as the prevalent cause of foodborne bacterial gastroenteritis. The spread of antimicrobial-resistant strains poses a serious threat to global public health and attracts attention worldwide, but information about clinical Campylobacter is relatively limited compared to isolates from food and animals. The current study illustrated the prevalence and antimicrobial resistance profiles of Campylobacter jejuni and Campylobacter coli isolates collected from a consecutive surveillance program between 2012 and 2019 in Shanghai, China, using antimicrobial susceptibility testing and whole-genome sequencing. Among the 891 Campylobacter strains (761 C. jejuni and 130 C. coli) isolates collected, high portions above 90% of resistance to ciprofloxacin, nalidixic acid, and tetracycline were observed for both C. jejuni and C. coli. The most common MDR profiles represented by C. jejuni and C. coli were combination of ciprofloxacin, tetracycline, florfenicol and nalidixic acid (5.39%), and azithromycin, ciprofloxacin, erythromycin, gentamicin, tetracycline, clindamycin, nalidixic acid (28.46%), respectively. The erythromycin resistance of C. coli (59.23%) is higher than C. jejuni (2.50%). A total of 76 erythromycin resistant isolates (16 C. jejuni and 60 C. coli) were sequenced using Illumina platform for determining the genotypes, antimicrobial resistance patterns and phylogeny analysis. Multilocus sequence typing (MLST) analysis showed a high genetic diversity with 47 sequence types (STs), including 4 novel alleles and 12 new STs. The most abundant clonal complexes (CCs) were CC-403 (31.25%) and CC-828 (88.33%) for C. jejuni and C. coli, respectively. Among the 76 erythromycin-resistant isolates, mutation A2075G in 23S rRNA and erm(B) gene were detected in 53.95 and 39.47%, respectively. The erm(B) gene was identified exclusively in 30 C. coli isolates. All these erm(B) positive isolates were multi-drug resistant. Furthermore, comparison of the erm(B)-carrying isolates of multiple sources worldwide demonstrated the possibility of zoonotic transmission of erm(B) in Campylobacter. These findings highlight the importance of continuous surveillance of erythromycin resistance dissemination in Campylobacter which may compromise the effectiveness of antimicrobial therapy.

Objectives: The emergence of the plasmid-mediated colistin resistance 1 ( mcr-1 ) of Escherichia coli has become a global health concern. This study reports the prevalence of mcr-1 among E. coli isolates from patients with diarrheal disease in Shanghai and the genetic characterization of mcr-1 -harbouring plasmids. Methods: A total of 1723 E. coli strains were collected from the faeces of patients with diarrheal disease in all sentinel hospitals in Shanghai from 2016 to 2021. Antimicrobial susceptibility testing was performed by broth microdilution and plasmid conjunction transfer assay was carried out using E. coli C600 as the recipient. The mcr-1 -positive E. coli strains (MCRPEC) were subjected to molecular characterization and bioinformatic analysis of the mcr-1 -bearing plasmids that they harboured. Results: Only 5 (0.28%) strains were found to harbour the mcr-1 gene using PCR screening. Plasmid conjugation assay and whole-genome sequencing indicated that EC16500, one MCRPEC strain that co-exhibited mcr-1, bla TEM-1 , bla OXA-1 , qnrS1, qnrS2, arr-3, and catB3 , could be conjugated to EC C600 by horizontal transfer with an average efficiency of 3.2 x 10 -5 . The plasmid pEC16500 harboured similar backbones as p70_2_15, pECGD-8-33, pNCYU-29-19-1_MCR1, and pIBMC_mcr1, and was shown to be encoded within a type IV secretion system (T4SS)-containing 32.6 kbp IncX4, next to the pap 2-like membrane-associated gene, to form a 2.4-kb cassette. Furthermore, sequencing and phylogenetic analyses revealed a similarity between other MCR-1-homolog proteins, indicating that the five E. coli isolates were colistin-resistant. Conclusion: Our data represents a significant snapshot of colistin resistance mcr-1 genes and highlights the need to increase active surveillance, especially among children under five years of age, in Shanghai. Great effort needs to be taken to avoid further dissemination of plasmid-mediated colistin resistance among clinically relevant Gram-negative bacterial pathogens. & COPY; 2023 Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

目的 了解2020-2022年上海市急性呼吸道感染(ARI)病例中病毒病原学构成和流行规律,为呼吸道疾病的防控提供数据支持.方法 以2020-2022年上海市监测哨点医院采集的4325例ARI病例标本为研究对象,利用多重聚合酶链式反应进行常见呼吸道病原体的检测,采用Excel 2211和SPSS 22.0软件对病毒检出结果进行统计分析.结果 4 325例ARI病例病毒检出率为17.80％(770,770/4 325),冬季为病毒感染的高峰季节.2020年检出率最高的病毒为鼻病毒/肠道病毒(HRV/HEV),2021-2022年检出率最高的为乙型流感病毒(FluB);流感病毒(IFV)、人偏肺病毒(hMPV)感染高峰在冬春两季,呼吸道合胞病毒(RSV)和副流感病毒(PIV)感染高峰在秋冬两季,全年都可观察HRV/HEV流行,腺病毒(ADV)和人博卡病毒(HBoV)没有明确的流行趋势;IFV是青年和中老年组ARI病例中最常检出的病毒,老年组中HRV/HEV检出率最高.结论 FluB和HRV/HEV是2020-2022年上海市成年人ARI病例中主要流行病毒病原体,不同呼吸道病毒的流行情况存在年龄和时间差异,应持续加强ARI病例的病原学监测.

Respiratory syncytial virus A (RSV-A) is one of the commonest pathogens causing acute respiratory tract infections in infants and children globally. The currently dominant circulating genotype of RSV-A, ON1, was first detected in Shanghai, China in 2011, but little data are available regarding its subsequent circulation and clinical impact here. In this work, we analyzed RSV-A infection in a cohort of patients hospitalized for acute respiratory infections in Shanghai Children's Hospital, and RSV-A was detected in ~10% of these cases. RSV-A G gene sequencing revealed that all successfully sequenced strains belonged to ON1 genotype, but in phylogenetic analysis, the majority of these sequences formed a clade separate from the four previously established lineages within ON1. The new lineage, denoted ON1-5, was supported by phylogenetic analyses using additional G gene sequences from RSV-A strains isolated in Shanghai and elsewhere. ON1-5 first appeared in 2015 in China and the Netherlands, and has since spread to multiple continents and gained dominance in Asia. In our cohort, ON1-5 was not associated with markedly different clinical presentations compared to other ON1 lineages. ON1-5 strains are characterized by four amino acid variations in the two mucin-like regions of G protein, and one variation (N178G) within the highly conserved CCD domain that is involved in receptor binding. These data highlight the continuous evolution of RSV-A, and suggest the possibility of the virus acquiring variations in domains traditionally considered to be conserved for fitness gain.

Although the highly effective measles vaccine has dramatically reduced the incidence of measles, measles, and outbreaks continue to occur in individuals who received the measles vaccine because of immunization failure. In this study, patients who have definite records of immunization were enrolled based on measles surveillance in Shanghai, China, from 2009 to 2017, and genomic characteristics regarding viruses retrieved from these cases provided insights into immunization failure. A total of 147 complete genomes of measles virus (MV) were obtained from the laboratory-confirmed cases through Illumina MiSeq. Epidemiological, and genetic characteristics of the MV were focused on information about age, gender, immunization record, variation, and evolution of the whole genome. Furthermore, systematic genomics using phylogeny and selection pressure approaches were analyzed. Our analysis based on the whole genome of 147 isolates revealed 4 clusters: 2 for the genotype H1 (clusters named H1-A, including 73 isolates; H1-B, including 72 isolates) and the other 2 for D8 and B3, respectively. Estimated nucleotide substitution rates of genotype H1 MV derived using genome and individual genes are lower than other genotypes. Our study contributes to global measles epidemiology and proves that whole-genome sequencing was a useful tool for more refined genomic characterization. The conclusion indicates that vaccination may have an effect on virus evolution. However, no major impact was found on the antigenicity in Shanghai isolates.

ObjectiveTo isolate and study the biological characteristics of severe acute respiratory syndrome coronavirus 2 （SARS-CoV-2） from feces of coronavirus disease 2019 （COVID-19） patients.MethodsVero E6 cells were used for virus isolation and the isolated strains were tested by nucleic acid test， immunofluorescence test， virulence test and whole genome sequencing. 50% tissue culture infective dose （TCID50） was calculated after the cell cultures of each generation were collectedResultsEight fecal specimens were inoculated with Vero E6 cells after treatment and cultured for 48 h. One specimen showed obvious cytopathic effect on Vero E6 cells. One SARS-CoV-2 out of 8 fecal samples from COVID-19 patients were isolated， and separation rate was 12.5%. The TCID50 of P1， P2 and P3 were 104.0/0.2 mL， 104.5/0.2 mL and 104.75/0.2 mL， respectively. Only one of the 8 stool samples had SARS-CoV-2 virus replication and amplification， and the Ct value of the nucleic acid detection was about 10. The sequence of the isolation was more than 99.99% homologous with that of Wuhan-Hu-1（GenBank MN908947）.ConclusionThe SARS-CoV-2 strain is isolated from the fecal samples of COVID-19 cases and is confirmed by genomic sequencing and immunofluorescence test， which indicates the presence of live virus in feces of COVID-19 cases.

Abstract Background China has experienced a continuous decreasing trend in the incidence of hepatitis A in recent years. Temporal trend analyses are helpful in exploring the reasons for the changing trend. Thus, this study aims to analyse the incidence trend of viral hepatitis A by region and age group in mainland China from 2004 to 2017 to evaluate the effectiveness of prevention and control measures. Methods Data on hepatitis A and population information were collected and analysed with a joinpoint regression model. Annual percentage changes (APCs) and average annual percentage changes (AAPCs) were estimated for the whole country and for each region and age group. Results From 2004 to 2017, the seasonality and periodicity of hepatitis A case numbers were obvious before 2008 but gradually diminished from 2008 to 2011 and disappeared from 2012–2017. The national incidence of hepatitis A (AAPC = − 12.1%) and the incidence rates for regions and age groups showed decreasing trends, with differences in the joinpoints and segments. Regarding regions, the hepatitis A incidence in the western region was always the highest among all regions, while a nonsignificant rebound was observed in the northeastern region from 2011 to 2017 (APC = 14.2%). Regarding age groups, the hepatitis A incidence showed the fastest decrease among children (AAPC = − 15.3%) and the slowest decrease among elderly individuals (AAPC = − 6.6%). Among all segments, the hepatitis A incidence among children had the largest APC value in 2007–2017, at − 20.4%. Conclusion The national annual incidence of hepatitis A continually declined from 2004 to 2017 and the gaps in hepatitis A incidence rates across different regions and age groups were greatly narrowed. Comprehensive hepatitis A prevention and control strategies, including the use of routine vaccination during childhood in mainland China, especially the implementation of the national Expanded Program on Immunization (EPI) in 2008, resulted in substantial progress from 2004 to 2017. However, gaps remain. Regular monitoring and analysis of hepatitis A epidemic data and prompt adjustment of hepatitis A prevention and control strategies focusing on children, elderly individuals and those living in certain regions are recommended.

Coxsackievirus A10 (CVA10) is one of the major causative agents of hand, foot and mouth disease (HFMD). To investigate the epidemiological characteristics as well as genetic features of CVA10 currently circulating in Shanghai, China, we collected a total of 9,952 sporadic HFMD cases from January 2016 to December 2020. In the past five years, CVA10 was the fourth prevalent causatives associated with HFMD in Shanghai and the overall positive rate was 2.78%. The annual distribution experienced significant fluctuations over the past five years. In addition to entire VP1 sequencing, complete genome sequencing and recombination analysis of CVA10 isolates in Shanghai were further performed. A total of 64 near complete genomes and 11 entire VP1 sequences in this study combined with reference sequences publicly available were integrated into phylogenetic analysis. The CVA10 sequences in this study mainly belonged to genogroup C and presented 91%–100% nucleotide identity with other Chinese isolates based on VP1 region. For the first time, our study reported the appearance of CVA10 genogroup D in Chinese mainland, which had led to large-scale outbreaks in Europe previously. The recombination analysis showed the recombination break point located between 5,100 nt and 6,700 nt, which suggesting intertypic recombination with CVA16 genogroup D. To conclusion, CVA10 genogroup C was the predominant genogroup in Shanghai during 2016–2020. CVA10 recombinant genogroup D was firstly reported in circulating in Chinese mainland. Continuous surveillance is needed to better understand the evolution relationships and transmission pathways of CVA10 to help to guide disease control and prevention.

In order to meet the needs of prevention and control of intestinal infectious diseases， a comprehensive surveillance for diarrheal diseases has been innovated and explored in Shanghai since 2012. The surveillance has extensive distribution of sentinel hospitals， systematic sampling， multi-pathogen collection， and hospital information system （HIS） as the basis， which has achieved “One system for surveillance of multiple diseases and one sample for detection of multiple pathogens". Continual active surveillance for the whole population has been conducted， covering demography， clinical information， epidemiology， pathogen detection， and drug sensitivity test for diarrhea cases. The surveillance has obtained preliminary achievements as follows. First， diarrheal diseases and their periodic changes have been characterized， in which the most prevalent pathogen of diarrhea is determined to be norovirus in Shanghai. Second， some rare pathogens and serotypes have been identified that may provide clues to the sources of outbreaks. Third， it facilitates the information sharing between public health institutions and clinical institutions， and provides scientific evidence for clinical diagnosis and treatment. In the future， Shanghai diarrhea comprehensive surveillance will be improved for expanding range and depth of surveillance， artificial intelligence assisted diagnosis and treatment， early warning of outbreaks， prediction of epidemic trends， and application of new detection technologies.

On April 27, 2022, an international flight KL857 from Amsterdam, the Netherlands arrived at Pudong International Airport, Shanghai Municipality. Passengers were transferred to the quarantine hotel for a routine 14-day medical observation in Songjiang District and regularly tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). One of the passengers (a 37-year-old Chinese male) was reported positive and diagnosed as a mild case on April 29. The case set out from Uganda (flight KL535) on April 25 and transferred at Amsterdam, the Netherlands on April 26 and Seoul, the Republic of Korea (KL857) on April 27. The patient has been vaccinated in four doses against coronavirus disease 2019 (COVID-19) (Beijing Institute of Biological Products Co., Ltd) in China and Uganda. After diagnosis, he was transferred to Shanghai Public Health Clinical Center for treatment. He recovered after treatment and was discharged on May 12. A nasopharyngeal swab from the patient was sampled on April 29 and sequenced using MGISEQ-200 (MGI TECH CO., LTD, Wuhan City, Hubei Province, China) on May 13. Genotyping analysis revealed that the patient was infected by SARS-CoV-2 variant of concern (VOC)/Omicron subvariant BA.5. The genome is most closely related to a sequence (GISAID ID: EPI_ISL_12713186) uploaded in South Africa (Figure 1) and 34 nonsynonymous mutations (T19I, A27S, G142D, V213G, G339D, S371F, S373P, S375F, T376A, D405N, R408S, K417N, N440K, L452R, S477N, T478K, E484A, F486V, Q498R, N501Y, Y505H, D614G, H655Y, N679K, P681H, N764K, D796Y, Q954H, N969K, and L24del, P25del, P26del, H69del, V70del) occurred in the spike gene matching the signature of the sublineage BA.5. The sequence of BA.5 was first uploaded to GISAID on March 15, 2022 from a patient’s nasopharyngeal and oropharyngeal swab collected on February 25 in South Africa. Together with BA.4, BA.5 has increased in prevalence in South Africa in recent weeks and has already spread to additional 19 countries in 3 months (total of 2,614 sequences submitted to GISAID);BA.5 caused a rise in the number of cases in some countries, such as Portugal, and South Africa has also reported a moderate increase in hospital admissions since late April (1). The L452R, F486V, and 69–70del mutations may impact the characteristics of BA.5 and make it appear to have a growth advantage over BA.1 and BA.2, which may mainly be driven by immune evasion (2-4). The 69–70del mutation is also responsible for S-gene target failure in polymerase chain reaction (PCR) tests, but PCR assays that include multiple gene targets will maintain accuracy for detecting this lineage (5-6). Due to the short duration of the epidemic, studies showed that the extent of vaccination and the high level of BA.2 waves in each country likely influence the emergence of BA.5 (7), but ongoing monitoring and assessment are needed to further elucidate the characteristics and impact of this lineage.

Introduction: Epidermolysis bullosa (EB) is a skin fragility disorder that is caused by molecular aberrations in the epidermal basement membrane zone. Based primarily on the cleavage plane within the skin, EB is classified into four major subtypes: EB simplex; junctional EB (JEB); dystrophic EB; and Kindler EB. The junctional form (JEB) can lead to blistering and a variety of extracutaneous complications, including genitourinary tract involvement. Despite therapeutic progress, treatment modalities for urological complications of JEB are currently limited. Results: We present the case of a Chinese male with intermediate JEB and profound urinary tract stenosis. Due to the progression of the urinary tract stenosis, he presented with repeated urological symptoms, such as high frequency of urination, painful urination, and difficult voiding. After birth, multiple blisters on the fingers, feet, and limbs, as well as nail dystrophies and spare hair were noted. Mutation analysis revealed that the patient carried a homozygous frameshift mutation in the LAMB3 gene [c.1172_1179delinsTGTGTGTGCAAGGAG/p. (P391Lfs*23)]. After receiving treatment for urethral dilatation, lingual mucosa for anterior urethroplasty, and repair of urethral stricture using a ventral onlay penile skin flap, the patient still experienced a relapse of urinary tract stenosis. Finally, the patient underwent perineal urethrostomy. In contrast, his older brother with similar urological symptoms received regular urethral dilatation, and the curative effect was positive. Conclusion: Here we report on a case with a novel LAMB3 mutation that led to JEB with profound urinary tract stenosis, which has expanded our experience in the treatment of EB urological complications.

克雅氏病(Creutzfeldt-Jakob disease,CJD)是一种在人类中最为常见的海绵状脑病,其致病因子为朊病毒.由于该病的致死率为100％,且具有传播风险,CJD的早期诊断对疾病防控具有重要意义.临床上一般依据患者的临床症状与体征以及相应的实验室检测来进行CJ D的鉴别诊断.本文主要围绕现有的CJ D实验室检测技术展开综述,包括朊病毒的直接与间接检测、疾病标志物的检测以及疾病相关基因PRNP的检测与分析等,旨在为进一步推广和规范CJ D的实验室检测提供参考与技术依据.

The global spread of SARS-CoV-2 is currently continuing, and the World Health Organization has announced the risk assessment of the viruses as high. In this study, we analyzed virology features of SARS-CoV-2 causing a family cluster outbreak. Among the six family members, five have been laboratory-confirmed infection of SARS-CoV-2 viruses. A total of five SARS-CoV-2 viruses have been isolated from the nasopharyngeal swabs. The complete genome of the viruses exhibited 100% nucleotide identity with each other. Only two nucleotide differences have been observed between genomes of the isolated viruses and the HCoV/Wuhan/ IVDC-HB-01/2019 strain. Therefore, SARS-CoV-2 has been confirmed as the causation of the family cluster infections.

On December 14, 2020, a 23-year-old female returning from the United Kingdom (UK) via airplane was tested by the laboratory of Shanghai Customs using nose swab to test for coronavirus disease 2019 .At 20:30 on December 14, Shanghai CDC received notification from the Shanghai Customs that the patient tested positive for COVID-19.By 22:00, the patient was transported by ambulance from the isolation point to the fever clinic of Jiading District Central Hospital.Due to travel history from the UK and abnormalities in nucleic acid test results, the hospital organized a consultation with experts and formed a recommendation to transfer the patient to Fudan University's Public Health Clinical Center for further diagnosis and treatment, which was carried out the following day.On December 15, Jiading District CDC retested using a nasopharyngeal swab sample and the nucleic acid result was positive for COVID-19.An epidemiological investigation revealed that the patient had a negative COVID-19 test result on December 12, 2020, two days before her flight to return to China.According to her statement, she had no exposure to symptomatic individuals and had not purchased or been exposed to frozen food products or raw meat.While remaining in the UK, the patient described running in a nearby park without wearing a mask and taking off her mask to eat and drink while waiting to board the plane.These are all potential situations for exposure, especially with 1.86 million confirmed cases of COVID-19 having been reported in the UK as of December 15, 2020.At the time of case report, the patient was diagnosed as a mild case according to the epidemiological investigation, symptoms and laboratory test.On December 24, the sample of the COVID-19 patient was sequenced using MGI MGISEQ-200 platform (Sequence ID: NC20SCU2740-1).This strain was dissimilar with the previous Shanghai strain detected in the Shanghai outbreak in November,

[目的]观察不同温度保存条件下细胞培养物中新型冠状病毒(简称"新冠病毒")存活情况,判断温度对病毒稳定性的影响,为新冠病毒肺炎疫情趋势研判及防控提供基础数据.[方法]将病毒接种于Vero E6细胞适应培养后,收获病毒液,根据所测得病毒半数组织培养感染剂量(TCID50)将不同稀释度(10-1、10-3、10-5、10-6)的病毒在不同温度下(4℃、22.5℃、37℃)保存1～7 d,并分别感染细胞,通过观察细胞病变效应(CPE)、实时荧光定量检测病毒核酸确定病毒感染性,以评价病毒在不同温度条件下的稳定性.[结果]不同浓度的新冠病毒在4℃条件下保存较为稳定,均具有感染性;22.5℃条件下,高浓度(10-1稀释度)病毒放置7d感染性逐渐下降,其他较低浓度病毒放置1d则完全失去感染性;37℃保存超过1d病毒即失去感染性.[结论]在细胞培养环境中,新冠病毒在4℃条件下高度稳定,对热敏感,且与病毒浓度相关,高浓度病毒室温22.5℃条件下仍可存活7d,37℃条件下放置1d病毒完全失活.