Cases of scarlet fever have increased since 2011 across China. However, genomic epidemiological knowledge of Streptococcus pyogenes, the causative agent, is limited. Here we present a longitudinal analysis of S. pyogenes isolates (n = 1,029) across emm1 and emm12 genotypes collected from eight provinces across China between 1993 and 2024. Genomic data integrated with national scarlet fever incidence data confirmed emm12 and emm1 as dominant genotypes underlying five incidence peaks and disease resurgence in 2024. Phylogenetic analysis showed independent evolution of these genotypes in China compared to global epidemic lineages. Four emm12 clades were present in China before 2011 but were replaced by a single clade, Clade II, by 2020. A dominant emm1 clade, M1china, distinct from global lineages and the M1UK lineage, represents >98% of emm1 cases in China. Sub-clade expansion coincides with carriage of integrative conjugative elements containing macrolide and tetracycline resistance genes and virulence gene-encoding prophage. Ongoing maintenance of these elements in emm1 and emm12 populations likely underlies the resurgence of scarlet fever in China.

Streptococcus pyogenes infections such as scarlet fever have increased in China since 2011. The genomic drivers of this increase are not known. The temporal clonal shifts within dominant emm12 and emm1 populations are unknown due to limited sampling. Based on a large longitudinal strain collection, we aimed to describe the molecular epidemiological characteristics and population structure of dominant S. pyogenesemm types circulating in China between 1993–2020.Here, we analyzed genomes of 945 China emm12 and emm1 isolates encompassing 1993–2020. The genomic data was integrated with national data on notifications of scarlet fever in the same period. The bacterial population structure and genomic features were analyzed to characterize the dynamics of circulating lineages during this period. We found there are five incidence peaks during 1993–2020 with S. pyogenes emm12 and emm1 being the dominant genotypes. The two genotypes driving scarlet fever in China have evolved independently of the global epidemic lineages. Four emm12 clades were evident prior to 2011, with a single clade replacing other emm12 populations by 2020. One dominant emm1 clade (termed M1china) represents > 98% of clinical cases in China since the 1980s, and diverged into three subclades that can be clearly distinguished from global epidemic lineages. Compared to clinical strains from the 1990s, selection and expansion of emm12 and emm1 sub-clades coincides with high carriage of drug resistance genes for macrolides and virulence-encoding prophage. The ongoing selection of multi-drug resistant mobile elements and prophage in both emm1 and emm12 populations underlie the resurgence of scarlet fever since 2011 in China. The first detection in China of a genotype M1UK isolate in 2018 warrants additional enhanced surveillance.

What is already known about this topic?:The H3N8 avian influenza virus (AIV) demonstrates considerable capacity for interspecies transmission and has been documented in multiple mammalian hosts, including equine and canine species. During 2022-2023, three laboratory-confirmed human infections with H3N8 were reported in China, heightening public health concerns about the zoonotic spillover potential of H3 subtype AIVs. What is added by this report?:This study reports the isolation of a genetically reassorted, low-pathogenicity H3N8 avian influenza virus (AIV) from an islet in Niukouyu Wetland Park, Beijing Municipality - the first detection of this viral strain in a wild environment within the city. Throat swabs collected from park staff tested negative for influenza viruses. Phylogenetic analysis demonstrated that the viral hemagglutinin gene originated from the Eurasian lineage, while the neuraminidase gene was derived from the North American lineage. Although no direct evidence of human infection has been documented, multiple mutations identified in the virus's internal genes are associated with enhanced replication capacity, increased virulence, and improved adaptation to mammalian hosts. These molecular features indicate a potential risk for cross-species transmission to humans. What are the implications for public health practice?:Given the potential threat that H3N8 AIVs pose to mammalian species, including humans, this study emphasizes the critical need to strengthen influenza surveillance networks and broaden monitoring efforts specifically targeting H3 subtype AIVs.

雷东多病毒是新发现的一种环状单链DNA病毒，分为Vientovirus和Brisavirus两个种，在人呼吸道中普遍存在，可引起呼吸道系统疾病。本文对雷东多病毒的基因组特征、致病性、流行病学、实验室检测等方面进行综述。

Objective:To characterize the epidemic of influenza in Beijing from 2022 to 2023 and the variation of gene and antigenicity of hemagglutinin (HA) of influenza A H3N2 virus, so as to provide scientific basis for influenza prevention and control in Beijing.Methods:Statistical analysis was carried out on the result of influenza pathogenic monitoring in Beijing from week 14, 2022 to week 20, 2023, and 79 strains of influenza A H3N2 virus were selected at different time and population sources, and their genetic variation and evolution characteristics were analyzed through HA gene amplification sequencing and antigenicity analysis.Results:From week 14, 2022 to week 20, 2023, 24 244 throat swabs of influenza like cases were collected in Beijing, and 4 987 influenza virus nucleic acid positive cases were detected, including 2 749 influenza A H3N2 positive cases, with a detection rate of 11.34%. Among the 79 strains, 50 strains (63.29%) showed low response, 94.44% of the strains from August to November 2022 had low response, and 54.10% of the strains from February to March 2023 had low response, with a statistically significant difference ( χ2=8.079, P=0.004). Compared with the vaccine strain A/Darwin/9/2021, the HA gene sequence of 79 strains of influenza A H3N2 showed nucleotide similarity of 97.47% to 98.47% and amino acid similarity of 97.05% to 98.17%. Genetic evolution analysis showed that the 18 strains isolated from August to November 2022 were all distributed in the 3C.2a1b.2a.1a.1 branch, while the 61 strains isolated from February to March 2023 all belonged to the 3C.2a1b.2a.3a.1 branch. Compared with the vaccine strain, there were multiple site mutations distributed at multiple antigenic determinants and receptor binding sites in A, B, C, D, and E. All strains had potential glycosylation sites of 8NST, 22NGT, 38NAT, 45NSS, 63NCT, 126NWT, 133NGT, 246NST, 285NGS, 483NET, while one strain missed 165NVT glycosylation sites; 55 strains between February and March 2023 missed 122NES glycosylation sites. Conclusions:The HA gene locus of influenza A H3N2 virus detected in Beijing from week 14, 2022 to week 20, 2023 showed multiple mutations, continuous monitoring of this subtype variation is crucial.

Objective:To understand the epidemic situation of Redondoviridae in Beijing and analyze its epidemiologic characteristics.Methods:Pharyngeal swab samples of healthy people and patients with acute respiratory infection in Beijing, including influenza like cases and severe acute respiratory infection (SARI) cases in hospitals were collected. Real time PCR was used to detect the nucleic acid of Redondoviridae. The positive samples were amplified and sequenced to analyze their species. The age and sex distribution of patients and species distribution of Redondoviridae were obtained through statistical analysis. Multiplex PCR was used to detect other common respiratory pathogens in the positive samples of Redondoviridae in influenza like cases and SARI cases, and the pathogenicity of Redondoviridae was analyzed.Results:The positive rates of Redondoviridae in healthy people and acute respiratory infection cases were 20.48% (189/923) and 11.23% (43/390), respectively, with a statistically significant difference ( P<0.05). The positive rate of male was higher than that of female in the healthy population, and the positive rate of the elderly group was higher than that of the adult group and the underage group, with a statistically significant difference ( P<0.05). The positive rate of male patients with acute respiratory tract infection was higher than that of female patients, but there was no significant difference. The proportion of Vientovirus in the positive samples of Redondoviridae was higher than that of Brisavirus, and the difference was statistically significant ( P<0.05). Among the throat swabs of respiratory tract infection cases, 43 were positive for Redondoviridae, of whom 24 were not detected for other pathogens. Conclusions:Redondoviridae widely exists in healthy people of all age groups in Beijing, and is also found in acute respiratory infection cases. The positive rate of Redondoviridae is different in different ages and genders. Both Vientovirus and Brisavirus were detected, and the proportion of Vientovirus was significantly higher than Brisavirus.

Objective:To investigate the phylogenetic and antigenic characteristics of hemagglutinin (HA) gene of influenza B/Victoria lineage (BV) viruses in Beijing during the 2021-2022 influenza surveillance season, and to analyze whether the circulating BV viruses match the vaccine strain.Methods:Pharyngeal swab specimens from influenza like-illness (ILI) cases in the 2021-2022 influenza surveillance season were collected from surveillance network labs in Beijing and cultured in MDCK cells and chicken embryo to isolate BV viruses. Nucleic acids of the viruses were extracted, and the HA gene was amplified and sequenced. The nucleotide and amino acid sequence identity of the HA gene was analyzed using MEGA5.0 software. A phylogenetic tree of HA gene was constructed using the maximum likelihood method. The N-glycosylation sites in HA were predicted online. Three-dimensional structure of HA was constructed using SWISS-MODEL homologous modeling. Hemagglutination inhibition (HI) test was performed to analyze the antigenicity of BV viruses.Results:A total of 402 BV viruses were collected and 58 strains with full-length HA gene sequences were chosen for further analysis. Compared with the HA gene of this year′s vaccine strain (B/Washington/02/2019), there were 27 amino acid mutations, 11 of which were located in four different antigenic determinants. The phylogenetic analysis revealed that three subgroups of 1A.3, 1A.3a1, and 1A.3a2 co-circulated in Beijing with 54 strains (54/58, 93.10%) clustered to the Clade 1A.3a2, two strains (2/58, 3.45%) clustered to the Clade 1A.3a1, and two strains (2/58, 3.45%) in the same subgroup (Clade 1A.3) as the vaccine component BV strain in 2021-2022. Compared with the vaccine strain (B/Washington/02/2019), two BV strains had an additional N-glycosylation site at residue 197, while the other 56 strains showed no change in N-glycosylation sites. Antigenic analysis showed that 35 BV strains (35/58, 60.34%) were antigenically similar to the vaccine strain and 23 strains (23/58, 39.66%) were low-response strains.Conclusions:Three subgroups of BV viruses co-circulated in Beijing during the 2021-2022 influenza surveillance season. The predominant subgroup was Clade 1A.3a2 (93.10%), showing a certain genetic distance with the vaccine strain (B/Washington/02/2019). Nearly 40% (39.66%) of the viruses were low-response strains. This study indicated that continuous monitoring of the variations of influenza epidemic strains and timely providing laboratory basis for screening vaccine component strains were the basic technical guarantee for coping with influenza pandemic.

Objective To identify the pathogen and track the genetic source of a cluster of cases with fever in a kindergarten in Fengtai district during the normalization of COVID-19 prevention and control in Beijing.Methods A descriptive analysis method was used to investigate this cluster of cases with fever in April 2021.Pharyngeal swabs were collected and viral nucleic acid was extracted, real-time PCR was performed to identify SARS-CoV-2 and other common respiratory virus. G gene of human metapneumovirus（hMPV） was amplified by RT-PCR and was then sequenced. BioEdit was used for G gene sequence analysis and the Neighbor-Joining model in MEGA 5. 0 software was used to construct the phylogenic tree of G gene. Results A total of 16 cases were reported in one class with the incidence of 53. 3%（16/30） during 8 days of a cluster outbreak. All pharyngeal swabs collected from 12 cases were tested SARS-CoV-2 negative, six were found to be hMPV positive by multiplex-PCR, and one was positive for both human adenovirus and hMPV. Full-length sequences of G genes were obtained from 2 strains of hMPV. Sequence analysis showed that both strains were hMPV B2 and the nucleic acid homology of G gene was 96. 73%-98. 01% with strains from Japan（LC337940, LC337935, LC1922349） in 2016 and over 98. 40%with strains from Shandong（OL625642, OL625644） in 2019, Henan MN944096 in 2019.Compared with the amino acid sequence of hMPV-B2 reference strain（AY297748）, six amino acid insertions containing EKEKEK were identified between 161-166 amino acid location and N-glycosylation of G protein analysis showed that the two strains had four N-glycosylation sites. Conclusions The leading pathogen for this cluster outbreak is found to be hMPV-B2, which are highly homologous with strains from Japan, Shandong and Henan. Therefore, a non-stop surveillance of hMPV is necessary during the normalization control and prevention period for COVID-19.

Viral isolation in cell cultures has been regarded for decades as the “gold standard” for the laboratory diagnosis of influenza viral infections. Not all viral strains could be isolated from clinical samples. This study aimed to quantify the viral load in the samples before isolation to save working time and improve working efficiency. Four hundred samples from patients with influenza-like cases were confirmed pdmH1N1 positive (200 cases) and B Victoria (BV) positive (200 cases) by whole-genome sequencing and analyzed by ddPCR for viral load in samples before isolation, and isolation results were verified by hemagglutination (HA) assay and hemagglutination-inhibition (HI) tests. Probit regression analysis was used to calculate the isolation viral load limit with a 95% probability level by SPSS 19.0 software. The results showed that the isolation limit of viral load was 4.9 × 104 (95% CI: 2.5 × 104–9.0 × 104) copies/mL for pdmH1N1 and 1.9 × 104 (95% CI: 7.8 × 103–3.6 × 104) copies/mL for BV. The isolation rate of clinical samples is positively correlated with the viral load in clinical samples, which can be used for viral culture, providing important guidance for daily work.

Objective:To analyze genetic and phylogenic characteristics of hemagglutinin (HA) gene of the first outbreak of influenza B Victoria virus (BV) in Beijing during 2021-2022 influenza epidemic.Methods:Pharyngeal swabs from influenza-like illnesses of the first influenza B outbreak in Beijing were collected. After extracting nucleic acid, the next generation sequencing (NGS) technology was used for sequencing and analysis. The Neighbor-Joining model of Mega 6.0 software was used to construct the phylogenic tree of HA gene, and the nucleotide and amino acid sequence identity were conducted.Results:Full-length sequence of two HA gene of BV strains were obtained by NGS. Compared with the HA gene of this influenza season vaccine strain (B/Washington/02/2019), there were nine amino acid mutations, six of which were located in three different antigenic determinants. Furthermore, the phylogenetic tree analysis showed that the HA gene of this outbreak were all located in Clade 1A.3a2 branch, not in the same strain of influenza vaccine recommended in the northern hemisphere 2021-2022 (B/Washington/02/2019).Conclusions:HA gene of this BV epidemic strain has many variations in antigenic epitopes. It is necessary to strengthen the surveillance and analysis of variation regularity of BV influenza, to provide a strong data support for BV prevention and control strategy for BV prevention and control strategy .

Objective:To understand the characteristics of hemagglutinin (HA) gene and antigenicity variation of influenza B Victoria lineage virus (BV) in Beijing in 2021, so as to provide scientific basis for influenza prevention and control in Beijing.Methods:The etiological surveillance results of influenza in Beijing from January to November 2021 were analyzed with statistical methods. Fifteen BV strains were randomly selected. The HA genes were amplified and sequenced. To analyze the gene mutation and evolutionary characters by hemagglutinin gene amplification and sequencing.Results:From January to November 2021, 16 097 samples of influenza like cases were collected. Two hundred and eight samples were positive by nucleic acid test. Two hundred and five samples were identified as BV (98.56%), and 3 samples were influenza B Yamagata lineage virus (1.44%). The similarity of nucleic acid and amino acid sequences between the 15 BV stains and the vaccine strain B/Washington/02/2019 were 98.39% - 98.75% and 97.86% - 98.40%, respectively. Phylogenetic analysis indicated that the 15 BV stains belonged to Clade1A.3a2. Multiple point mutations existed compared to the vaccine stain. There were 11 glycosylation sites in the 15 BV strains. One strains (6.6%) was a low response strain of the vaccine strain.Conclusions:BV strains were predominant among the influenza viruses observed in Beijing in 2021. HA gene loci showed multiple mutations, suggesting the importance of continuous surveillance of the mutations in this subtype for providing a scientific basis for influenza prevention and control strategies formulation.

Coronavirus disease 2019 (COVID-19) has spread widely around the world, and in-depth research on COVID-19 is necessary for biomarkers and target drug discovery. This analysis collected serum from six COVID-19-infected patients and six healthy people. The protein changes in the infected and healthy control serum samples were evaluated by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and high-performance liquid chromatography (HPLC). The differential protein signature in both groups was retrieved and analyzed by the Kyoto Encyclopedia of Gene and Genomes (KEGG), Gene ontology, COG/KOG, protein–protein interaction, and protein domain interactions tools. We shortlisted 24 differentially expressed proteins between both groups. Ten genes were significantly up-regulated in the infection group, and fourteen genes were significantly down-regulated. The GO and KEGG pathway enrichment analysis suggested that the chromosomal part and chromosome were the most enriched items. The oxytocin signaling pathway was the most enriched item of KEGG analysis. The netrin module (non-TIMP type) was the most enriched protein domain in this study. Functional analysis of S100A9, PIGR, C4B, IL-6R, IGLV3-19, IGLV3-1, and IGLV5-45 revealed that SARS-CoV-2 was closely related to immune response.

Since 2010 the year when it was first reported in domestic ducks in China, highly pathogenic avian influenza (HPAI) H5N8 has caused several outbreaks in different countries. The first outbreak wave was documented in South Korea and Japan in 2014 and the second wave was reported in Asian and European countries in 2016. More importantly, zoonotic infection was first reported in poultry workers in Russia in 2021. Therefore, active surveillance on H5N8 is highly needed. Surveillance on live birds instead of environmental samples is commonly reported. In the present study, we reported detection and genomic characterization of an environmental H5N8 strain in environmental samples of Tongzhou poultry meat markets in Beijing on a monthly basis from March 2021 to February 2022. Among 600 samples screened, a total of 27 samples were positive for influenza A virus with 4 typed as H5N8, 10 H7N9, and 13 H9N2. Whole genome sequencing and analysis of one duck neck with a higher virus load showed that A/Environment sample/Beijing/TZ001/20 21 (H5N8) clade 2.3.4.4b had the highest identities (over 99%) in all eight segments with H5N8 isolates from wild birds swan and tern in Hubei and had polybasic cleavage site PLREKRRKR/G, characteristic of a HPAI virus. Overall, our data indicate that HPAI H5N8 virus is still circulating in domestic ducks in China in the study period and continued surveillance in domestic and wild birds is needed to control H5N8.

Objective:To clarify the M protein ( emm gene) types and drug susceptibility characteristic variations of Group A Streptococcus (GAS) in children in Beijing. Methods:The GAS strains isolated from throat swab samples of children diagnosed with scarlet fever and pharyngeal infection in scarlet fever etiology surveillance sentinel hospitals in 16 districts of Beijing in 2018, 2019 and 2021 were analyzed retrospectively.PCR amplification and sequencing were used for emm genotyping, and the minimum inhibitory concentrations (MIC) of 10 antibiotics were determined by the broth microdilution method.The data were analyzed using χ2 test and Fisher′ s exact method between groups. Results:A total of 557 GAS strains were collected, and 11 emm genotypes ( emm1, emm3, emm4, emm6, emm11, emm12, emm22, emm75, emm89, emm128, and emm212) were detected.Of 557 strains, 238 trains were of emm1 type (42.73%), 271 strains were of emm12 type (48.65%) and 48 strains were of other emm types (8.62%). The detection rates of emm1, emm12 and other emm type genes in 2018, 2019, and 2021 were [37.50% (105/280 strains), 57.14% (160/280 strains), 5.36% (15/280 strains)], [49.05% (129/263 strains), 39.54% (104/263 strains), 11.41% (30/263 strains)], and [28.57% (4/14 strains), 50.00% (7/14 strains), 21.43% (3/14 strains)], respectively.In children infected with emm12 in 2018 and 2019, there were more children under 6 years old than children over 6 years old (62.50% vs.46.88%, 46.36% vs.30.36%) (χ 2=7.182, 6.973; all P<0.05). Drug susceptibility testing results suggested that 225 randomly selected GAS strains were all 100.00% sensitive to 7 antibiotics including Penicillin, Levofloxacin, Meropenem, Linezolid, Cefotaxime, Cefepime and Vancomycin.The rates of resistance to Erythromycin, Tetracycline and Clindamycin were [88.57% (93/105 strains), 87.62% (92/105 strains), 86.67% (91/105 strains)], and [94.34% (100/106 strains), 94.34% (100/106 strains), 87.74% (93/106 strains)] in 2018 and 2019, respectively.The test strains were 100.00% (14/14 strains) resistant to the above 3 antibiotics in 2021.MIC 50 and MIC 90 values of Penicillin in 2018, 2019, and 2021 were (0.03 mg/L, 0.03 mg/L), (0.03 mg/L, 0.06 mg/L), and (0.06 mg/L, 0.06 mg/L), respectively.Among 225 GAS strains, 207 strains had drug resistance and were resistant to more than one drug.Specifically, 94.69% (196/207 strains) were resistant to Erythromycin, Tetracycline and Clindamycin.About 4.35% (9/207 strains) were resistant to both Erythromycin and Clindamycin.A total of 0.97% (2/207 strains) were resistant to Erythromycin and Tetracycline. Conclusions:The emm genotypes of GAS in children in Beijing are diverse in 2018, 2019 and 2021.The dominant genotypes are emm12 and emm1, and emm12 is the main epidemiological type.GAS strains maintain highly resistant to Erythromycin, Clindamycin and Tetracycline, and sensitive to Penicillin and other antibiotics.However, MIC 50 and MIC 90 of Penicillin shows an ascending trend.

目的 探索北京市怀柔区11种常见呼吸道传染病病原体的流行规律.方法 从哨点医院每月收集约20例急性呼吸道感染病例,采集呼吸道样本,进行11种常见呼吸道病原体的核酸检测,并对病例进行个案调查.结果 2015-2020年,共监测到急性呼吸道感染病例1 579例,11种病原体总阳性率为24.00％(95％CI:21.90％～26.10％),检出率前3位分别为:流感病毒6.08％(95％CI:4.90％～7.26％)、副流感病毒3.74％(95％CI:2.80％～4.68％)、肺炎支原体3.29％(95％CI:2.41％～4.17％);大多数病原体每年呈单峰模式流行,流感病毒、呼吸道合胞病毒的流行季主要为冬春季;副流感病毒的流行季主要为夏秋季;肺炎支原体的流行季主要为秋冬季.8.18％(95％CI:5.42％～10.94％)的阳性病例为2种及以上病原体的混合感染.对患者的外周血淋巴细胞计数进行分析,发现28.00％(95％CI:10.30％～35.60％)的鼻病毒阳性病例,24.32％(95％CI:14.54％～34.10％)的流感病毒阳性病例,22.22％(95％CI:3.01％～41.43％)的冠状病毒阳性病例,外周血淋巴细胞计数减少(低于0.8×109/L).结论 本研究初步摸清怀柔区2015-2020年11种呼吸道病原体(特别是流感病毒之外的病原体)流行强度、流行季节、好发人群等特征,对怀柔区呼吸道传染病防控工作具有重要意义.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has lasted for two years and caused millions of infections and deaths in humans. Although the origin of SARS-CoV-2 infection in humans remains unknown, infection in animals has been frequently reported in varieties of animals all over the world. Both experimental and natural infections of SARS-CoV-2 in different animal species provide useful information on viral host range and pathogenicity. As the pandemic continues to evolve, SARS-CoV-2 infection in animals will be expanding. In this review, we summarized SARS-CoV-2 testing and infection in animals as well as SARS-CoV-2 strains and transmission in animals. Current data showed that at least 18 different animal species tested positive for SARS-CoV-2. These 18 animal species belong to pet, captive, farmed, and wild animals. Fifteen of the eighteen animal species were known to be positive for the Delta variant and ten animal species were infected with two different types of variants. Human-to-animal, animal-to-animal, and animal-to-human transmission events were suggested in different outbreaks involved in animal infection with SARS-CoV-2. Continued testing, immunization, and surveillance are warranted.

Objective:To analyze the genetic evolution and mutation of the first case of human infection with highly pathogenic avian influenza (HPAI) virus H5N8 in the world, so as to provide scientific basis for the prevention and control of HPAI H5N8.Methods:The complete genomic sequences of HPAI H5N8 viruses were searched from the Global Initiative on Sharing All Influenza Data (GISAID) database. Phylogenetic trees were generated by maximum likelihood (ML) method using MEGA software. The key genetic variations in the genome were analyzed.Results:The highly pathogenic avian influenza virus H5N8 belonged to clade 2.3.4.4b. The genomes of the virus had high similarity (99%~100%) with the virus genomes of A/chicken/Astrakhan/2171-1/2020, A/chicken/Astrakhan/321-10/2020 and A/chicken/Astrakhan/321-06/2020. The receptor binding site at the position aa222-224 in HA gene was QRG (H5 encoding). The virus was preferentially bound to avian α-2,3-linked sialic acids receptor. No mammalian adaptive amino acid mutation sites, such as E627K and D701N, were found in PB2 gene. NA and M2 genes had no resistance mutations to neuraminidase inhibitors and amantadine. The virus remained to be sensitive to antiviral therapy.Conclusions:The current highly pathogenic avian influenza virus H5N8 has not adapted to humans and had no ability of human-to-human transmission. Surveillance for avian influenza virus H5N8 should be maintained.

Objective:To investigate the relationship between rs12252 polymorphism of interferon-induced transmembrane protein 3 (IFITM3) gene and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.Methods:A total of 446 new cases of coronavirus disease 2019 (COVID-19) and asymptomatic carriers identified by the surveillance in Beijing from January 2020 to January 2021, and 65 healthy control individuals were enrolled in this study. The genomic DNA was extracted from respiratory samples. The polymorphism of rs12252 in IFITM3 gene was determined by Sanger sequencing.Results:No statistically significant differences in distribution of rs12252 polymorphism in IFITM3 was observed between controls and asymptomatic carriers, mild cases, or common cases ( P>0.05). However, the difference between controls and severe cases was statistically significant ( P<0.05). The CC genotype was observed in 60% of severe cases, which was significant higher than that of other types of cases, asymptomatic carriers, and controls. Recessive genetic model suggested that COVID-19 cases with CC genotype had higher risk of developing into severe or critical cases than those with CT or TT genotype (O R=3.546, 95% CI: 1.084-11.595). Conclusions:The CC genotype of rs12252 in IFITM3 gene may related to higher risk of developing into severe or critical cases of COVID-19.

目的 对北京某医院就诊的一例人感染猪链球菌患者的血培养分离菌株,并进行分子分型与耐药检测分析.方法 将患者血培养阳性物接种于哥伦比亚血琼脂平板,分离培养后提取菌株DNA,采用多位点序列分型(MLST)确定其分子型别;采用微量肉汤稀释法进行12种抗生素的药敏试验.结果 该菌株的多位点序列分型为ST1型.药敏试验结果表明:该菌对青霉素、左氧沙星、美罗培南、万古霉素、克林霉素、头孢噻肟、利奈唑胺、红霉素和头孢吡肟9种常用抗生素敏感;对氧氟沙星中度敏感;对四环素和氯霉素耐药.结论 该猪链球菌为ST1型,是引起脑膜炎的主要型别;对9种常用抗生素菌敏感,可做为临床治疗的参考用药.

Scarlet fever has been resurgent in China for more than 8 years. With ever more regions reporting increasing incidence, control of the outbreak throughout the country is challenging without an available vaccine.1You Y Davies MR Protani M et al.Scarlet fever epidemic in China caused by Streptococcus pyogenes serotype M12: epidemiologic and molecular analysis.EBioMedicine. 2018; 28: 128-135Summary Full Text Full Text PDF PubMed Scopus (47) Google Scholar Emergent Streptococcus pyogenes M types or subclones can lead to fatal outbreaks and are a huge threat to global public health.2Nasser W Beres SB Olsen RJ et al.Evolutionary pathway to increased virulence and epidemic group A streptococcus disease derived from 3615 genome sequences.Proc Natl Acad Sci USA. 2014; 111: e1768-e1776Crossref PubMed Scopus (181) Google Scholar We read with interest the Article by Nicola N Lynskey and colleagues3Lynskey NN Jauneikaite E Li HK et al.Emergence of dominant toxigenic M1T1 Streptococcus pyogenes clone during increased scarlet fever activity in England: a population-based molecular epidemiological study.Lancet Infect Dis. 2019; 19: 1209-1218Summary Full Text Full Text PDF PubMed Scopus (48) Google Scholar on the emergence of the dominant toxigenic M1T1 S pyogenes clone during increased scarlet fever activity in England. Lynskey and colleagues emphasise the need for molecular surveillance of S pyogenes for timely detection of emergent M types or toxigenic clones, which aids in the understanding of epidemic trends. Scarlet fever is a notifiable disease in China, but surveillance of S pyogenes M type is rarely involved.1You Y Davies MR Protani M et al.Scarlet fever epidemic in China caused by Streptococcus pyogenes serotype M12: epidemiologic and molecular analysis.EBioMedicine. 2018; 28: 128-135Summary Full Text Full Text PDF PubMed Scopus (47) Google Scholar Here we report an 8-year surveillance study of S pyogenes M type during 2011–18 in Beijing. 24 590 respiratory throat swab samples were collected from patients with scarlet fever and streptococcal infection; 2484 strains were isolated and analysed for emm type. Coincident with a decline in scarlet fever notifications in Beijing since 2012, the frequency of M12 S pyogenes started to decline from 2011, whereas M1 started to increase and then exceeded M12 in 2013 and 2014, when the scarlet fever incidence began to increase. Since 2014, non-predominant types have increased in frequency. Notably, numbers of M128 increased substantially in 2017 and of M3 in 2018 (figure; appendix). In view of these findings, we speculate that regional herd immunity against M12 serotype has become established in susceptible populations in Beijing. The increasing frequency of M1 is alarming, and epidemic trends of both scarlet fever and invasive S pyogenes infections caused by M1 should be given more attention. Furthermore, further population genetic analysis in a global context is required. The emergence of M128 and M3, and the increasing frequency of other non-predominant M types, reflect diversification of respiratory S pyogenes strains in Beijing. With no herd immunity, populations in Beijing are at high risk of scarlet fever epidemics caused by these types. This study was the first long-term and largest surveillance of S pyogenes M type in the past 8 years of scarlet fever resurgence in China. Public health facilities should pay increasing attention to M type shift. With more frequent domestic and global transportations, long-term, nationwide, active surveillance of M type is necessary to monitor the spread of emergent clones. YY and XP contributed equally. We declare no competing interests. Download .pdf (.09 MB) Help with pdf files Supplementary appendix Emergence of dominant toxigenic M1T1 Streptococcus pyogenes clone during increased scarlet fever activity in England: a population-based molecular epidemiological studyA dominant new emm1 S pyogenes lineage characterised by increased SpeA production has emerged during increased S pyogenes activity in England. The expanded reservoir of M1UK and recognised invasive potential of emm1 S pyogenes provide plausible explanation for the increased incidence of invasive disease, and rationale for global surveillance. Full-Text PDF Open Access