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Hepatitis E virus (HEV) is a prevalent pathogen responsible for acute viral hepatitis, HEV genotypes 3 and 4 infections causing zoonotic infections. Currently, the nucleotide similarity analysis between humans and pigs for HEV genotype 4 is limited. In this study, stool samples from an HEV‐infected patient who is a pig farmer and from pigs were collected to obtain the near full‐length genome of HEV, phylogenetic trees were constructed for genotyping, and similarity of HEV sequences was analyzed. The results showed that HEV‐RNA was detected in the stool samples from the patient and six pigs (6/30, 20.0%). Both HEV subtype in the patient and pigs was 4b. Additionally, similarity analysis showed that the range was 99.875%–99.944% between the patient and pigs at the nucleotide level. Four isolates of amino acid sequences (ORFs 1–3) from pigs were 100% identical to the patient. Phylogenetic tree and similarity analysis of an additional nine HEV sequences isolated from other patients in this region showed that the HEV sequence from the pig farmer had the closest relationship with the pigs from his farm rather than other sources of infection in this region. This study provides indirect evidences for HEV subtype 4b can be transmitted from pigs to humans at the nucleotide level. Further research is needed to explore the characteristics of different HEV subtypes. [ABSTRACT FROM AUTHOR]

Emerging pathogenic tick‐borne viruses (TBVs) have attracted a great deal of attention due to their significant impact on human and animal health. A novel orthonairovirus named Dadong virus (DDV) was isolated from Haemaphysalis concinna ticks in the Changbai Mountain region on the China–North Korea border. DDV can induce cytopathic effects in mammalian and human cell lines. Phylogenetic analysis showed that it belongs to the genus Orthonairovirus, family Nairoviridae, exhibiting 72.4%–81.3% nucleic acid identity to Tofla orthonairovirus, known to cause lethal infection in IFNAR KO mice. The first serological evidence of DDV circulating in cattle and mice was also obtained, with 4.0% (1/25) of cattle and 2.27% (1/44) of mice seropositive for DDV. Further investigations, including serological surveys using human samples, are required to assess the public health risk posed by DDV. [ABSTRACT FROM AUTHOR]

• Human metapneumovirus (HMPV) is an important respiratory pathogen that causes acute respiratory tract infection in children ≤5 years old. • The prevalence peak of HMPV in southern China appeared between March and May. • Respiratory syncytial virus is the most common respiratory virus coinfected with HMPV in children. • The predominant subtype of HMPV in this area is B1, followed by A2c subtype. • Long sunshine duration might decrease the HMPV prevalence. This study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. 14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. HMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. HMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence. [ABSTRACT FROM AUTHOR]

This study was performed to investigate the presence and characteristics of the oxazolidinone resistance genes optrA and cfr(D) in Streptococcus parasuis. In total, 36 Streptococcus isolates (30 Streptococcus suis isolates, 6 Streptococcus parasuis isolates) were collected from pig farms in China in 2020–2021, using PCR to determine the presence of optrA and cfr. Then, 2 of the 36 Streptococcus isolates were further processed as follows. Whole-genome sequencing and de novo assembly were employed to analyze the genetic environment of the optrA and cfr(D) genes. Conjugation and inverse PCR were employed to verify the transferability of optrA and cfr(D). The optrA and cfr(D) genes were identified in two S. parasuis strains named SS17 and SS20, respectively. The optrA of the two isolates was located on chromosomes invariably associated with the araC gene and Tn554, which carry the resistance genes erm(A) and ant(9). The two plasmids that carry cfr(D), pSS17 (7550 bp) and pSS20-1 (7550 bp) have 100% nucleotide sequence identity. The cfr(D) was flanked by GMP synthase and IS1202. The findings of this study extend the current knowledge of the genetic background of optrA and cfr(D) and indicate that Tn554 and IS1202 may play an important role in the transmission of optrA and cfr(D), respectively. [ABSTRACT FROM AUTHOR]

The H10 subtypes of avian influenza viruses pose a continual threat to the poultry industry and human health. The sporadic spillover of H10 subtypes viruses from poultry to humans is represented by the H10N8 human cases in 2013 and the recent H10N3 human infection in 2021. However, the genesis and characteristics of the recent reassortment H10N3 viruses have not been systemically investigated. In this study, we characterized 20 H10N3 viruses isolated in live poultry markets during routine nationwide surveillance in China from 2014 to 2021. The viruses in the recent reassortant genotype acquired their hemagglutinin (HA) and neuraminidase (NA) genes from the duck H10 viruses and H7N3 viruses, respectively, whereas the internal genes were derived from chicken H9N2 viruses as early as 2019. Receptor‐binding analysis indicated that two of the tested H10N3 viruses had a higher affinity for human‐type receptors than for avian‐type receptors, highlighting the potential risk of avian‐to‐human transmission. Animal studies showed that only viruses belonging to the recent reassortant genotype were pathogenic in mice; two tested viruses transmitted via direct contact and one virus transmitted by respiratory droplets in guinea pigs, though with limited efficiency. These findings emphasize the need for enhanced surveillance of H10N3 viruses. Importance: Avian influenza virus, which frequently jumps to humans and causes severe illness and death, poses a continuing threat to public health. Understanding the genesis and characteristics of avian influenza viruses will help prevent future human influenza pandemics. In this study, we provide evidence that the human‐infecing H10N3 viruses are reassortants with internal genes from chicken H9N2 viruses and surface genes from duck viruses, suggesting a critical role for ducks in the generation of viruses with human‐infecting potential. Our findings demonstrate that some H10N3 viruses exhibit higher affinity for human‐type receptors than for avian‐type receptors, and some can transmit via direct contact and/or respiratory droplets in the guinea pig model, suggesting the potential risk posed by H10N3 viruses. [ABSTRACT FROM AUTHOR]

The resurgence of Bordetella pertussis infections leading to whooping cough is a concern in many parts of the world. The number of pertussis cases in China has increased significantly since 2013. In this study, whole-genome sequencing analysis was performed for 388 B. pertussis strains isolated in China from the 1970s to 2018, combining 594 published strains from around the world. This study revealed that lineage V diverged about 50 years ago in China, while lineage IV is dominant in the other countries. It also revealed that the erythromycin-resistant sub-lineages Va, Vb, and Vc with limited genomic variation emerged 11 ~ 12 years ago. These three sub-lineages were identified after the co-purified acellular vaccines (cp-ACVs) completely replaced the previous whole cell vaccines (WCVs) after the national immunization program of 2012. It suggests that the cp-ACVs cannot induce immunity that is potent enough to restrict the spread of the lineage V, antibiotic abuse further favors the spread of this lineage in China. These findings demand a reassessment of the immunization strategy and development of new vaccines in China to stop the resurgence and drug resistance of B. pertussis. [ABSTRACT FROM AUTHOR]

• The epidemiological and virological characteristics of H7N9 avian influenza virus in the newly affected western Chinese provinces were analyzed. • A delayed peak of human infections was observed. • G11 and G3 were the dominant genotypes of prevalent low pathogenic (LP)- and highly pathogenic (HP)-H7N9 virus, respectively. • Reassortment has been ongoing. Eight additional provinces in western China reported human infections for the first time during the fifth wave of human H7N9 infections. The aim of this study was to analyze the epidemiological and virological characteristics of this outbreak. The epidemiological data of H7N9 cases from the newly affected western Chinese provinces were collected and analyzed. Full-length genome sequences of H7N9 virus were downloaded from the GenBank and GISAID databases, and phylogenetic, genotyping, and genetic analyses were conducted. The peak of human infections in the newly affected western Chinese provinces was delayed by 4 months compared to the eastern Chinese provinces, and both low pathogenic (LP) and highly pathogenic (HP) H7N9-infected cases were found. The LP- and HP-H7N9 virus belonged to 10 different genotypes (including four new genotypes), of which G11 and G3 were the dominant genotypes, respectively. Almost all of these viruses originated from eastern and southern China and were most probably imported from neighboring provinces. Genetic characteristics of the circulating viruses were similar to those of the viruses from previously affected provinces during Wave Five. A delayed peak of human infections was observed in the newly affected western Chinese provinces, and reassortment has been ongoing since the introduction of H7N9 viruses. This study highlights the importance of continued surveillance of the circulation and evolution of H7N9 virus in western China. [ABSTRACT FROM AUTHOR]

Adeno-associated virus (AAV; genus Dependoparvovirus, family Parvoviridae) was first discovered in 1965 as a contaminant in adenovirus preparations. The AAVs are generally considered nonpathogenic, and they have the ability to attenuate the replication of other more pathogenic viruses, which makes them attractive as potential therapeutics or preventative measures. This study characterized a novel AAV isolated from Muscovy ducks in China. The novel virus (MHH-05-2015) was isolated after propagating a field isolate of the DAdV-3 virus (a type 3 duck adenovirus) in duck embryo fibroblasts. The full genome sequence of MHH-05-2015 was determined, and the nucleotide and amino acid sequences were compared to other avian AAVs. The genomic distribution of the structural and non-structural protein-coding genes in MHH-05-2015 was conserved and consistent with the other AAVs. Compared to previously isolated avian AAVs, MHH-05-2015 had approximately 63 to 64% sequence identity. Phylogenetic analysis indicated that MHH-05-2015 clustered separately from other avian AAVs, suggesting that MHH-05-2015 was not directly descended from other Dependoparvovirus family members. These results suggest that MHH-05-2015 is a new subtype of AAV that is distinct from other avian AAVs. [ABSTRACT FROM AUTHOR]

This study aimed to characterize a novel adenovirus (AdV) isolated from diseased Muscovy ducks in China. After the AdV was successfully propagated in duck embryo fibroblasts, the morphological and physicochemical properties of the virions were studied by electron microscopy and different tests. The results of the analyses were in conformity with AdV properties. The full genome sequence was determined and analyzed. The new isolate (named CH-GD-12-2014) shared over 91% sequence identity with duck AdV-2 representing the species Duck aviadenovirus B. The most important distinguishing feature between the two DAdV strains was the presence of a second fiber gene in the Chinese isolate. Phylogeny reconstruction confirmed the affiliation of the virus with goose and duck AdVs in the genus Aviadenovirus . Experimental infection resulted in embryo death, and intramuscular inoculation provoked morbidity and mortality among ducks and chickens. [ABSTRACT FROM AUTHOR]

Influenza B virus is a major causative agent of respiratory disease in humans. Our study of an outbreak of influenza B virus in Wenzhou from 2011 to 2014 revealed that 163 (5.58 %) of 2921 samples were influenza B positive. Sequencing of the hemagglutinin and neuraminidase genes showed substitutions at the amino acid level. Phylogenetic analysis revealed co-circulation of the B/Victoria and B/Yamagata lineages in the Wenzhou area from 2011 to 2014. Multiple viral introductions from both Chinese and international sources played important roles in endemic co-circulation and transmission in coastal southeastern China. [ABSTRACT FROM AUTHOR]

This study reports the complete genome sequence of an infectious bronchitis virus (CK/CH/SD/121220, KJ128295) isolated in 2012 from Shandong Province in northern China. The genome is 27,666 nt long, comprising six genes and 5′ and 3′ untranslated regions. The full-length genome of the CK/CH/SD/121220 isolate had the highest nucleotide sequence identity (96.7 %) to the YX10 strain. Sites of recombination were identified in the genes 1ab, S, 5a, 5b and N, with their putative parental strains belonging to the QX- and YN-type subgroups, which are already circulating in China. Our findings suggest an important role played by recombination in IBV evolution. [ABSTRACT FROM AUTHOR]

Historically, Reston virus (RESTV) has been found to be associated with outbreaks of disease only in nonhuman primates. Its spread to domestic pigs was reported for the first time in 2008. In this study, we report the discovery, molecular detection, and phylogenetic analysis of Reston virus (RESTV) in domestic pigs in China. A total of 137 spleen specimens from pigs that died after showing typical clinical signs of porcine reproductive and respiratory syndrome (PRRS), and for which infection with porcine reproductive and respiratory syndrome virus (PRRSV) was confirmed by RT-PCR, were collected from three farms in Shanghai from February to September 2011. Of these samples, 2.92 % (4/137) were found to be positive for RESTV. All of the positive piglets were under the age of 8 weeks and were co-infected with PRRSV. Sequences were found that shared 96.1 %-98.9 % sequence similarity with those of two RESTV variants that had been discovered previously in domestic pigs and cynomolgus macaques from the Philippines. We therefore conclude that RESTV was present in domestic pigs in Shanghai, China. [ABSTRACT FROM AUTHOR]

Background Human adenovirus 55 ( HAdV-55) has caused recent outbreaks of acute respiratory disease ( ARD) among adults and military trainees. The active surveillance for HAdV infections was sparse in China, and current knowledge on the HAdV-type distributions and its molecular evolution is lacking. Objectives To acquire better understanding on the prevalence and molecular evolution of HAdV-55 strains in China, for an informed strategy for disease control and prevention. Population/Methods Nasopharyngeal aspirates were collected from hospitalized children with ARTI in Chongqing during 2009-2012. The genotype of HAdV isolates were determined by sequencing the partial hexon and fiber genes. Whole genome sequences of HAdV-55 were obtained for molecular evolution analysis. Results About 191 (8·55%) HAdV were detected in 2234 children, including 92 (48·2%) with HAdV-7, 72 (37·7%) with HAdV-3, 6 (3·1%) with HAdV-55, 5 (2·6%) with HAdV-5, 4 (2·1%) with HAdV-1, 1 (0·5%) with HAdV-2, and 11(5·8%) with untyped HAdV. Four of these children developed pneumonia, two of whom were diagnosed with severe pneumonia and/or encephalopathy. HAdV-55 isolates clustered with HAdV-11 sequences based on the hexon gene and clustered with HAdV-14 sequences based on the fiber gene and the whole genome. The overall evolutionary rates of hexon gene, fiber gene, and whole genome of HAdV-55 were estimated at 6·2 × 10−5 s/s/y, 8·0 × 10−5 s/s/y, and 1·7 × 10−5 s/s/y, respectively. Conclusions This study suggested HAdV-55 as an emerging infectious disease pathogen has conserved genetic structure and is closely related to each other. Further molecular investigation based on HAdV-55 of wider origin might facilitate understanding its diversity, dissemination, and transmission in China. [ABSTRACT FROM AUTHOR]

Highlights: [•] The porcine EMCV BD2 was isolated from northern China. [•] The BD2 isolate could replicate in BHK-21 cells and reach a peak titer by 16hpi. [•] Phylogenetic analyses revealed that the BD2 isolate belonged to group I. [ABSTRACT FROM AUTHOR]

In this study, we report the complete nucleotide sequence of porcine kobuvirus CH/HZ/2011 (CH/HZ) isolated from infected piglets in China. Dendrograms indicated that CH/HZ is closely related to other porcine kobuviruses. The complete genome sequence of CH/HZ has an adenine insertion at position 124, an 18-nt deletion in the 5′UTR, and a 90-nt deletion in the 2B coding region. A neighbor-joining tree based on the VP1 gene indicated that 31 porcine kobuvirus strains are divided into four clusters (Thai-Japanese group, Hungarian group, Chinese group I and Chinese group II). The strain CH/HZ was included in Chinese group II. [ABSTRACT FROM AUTHOR]

To analyze the epidemiology of PRRSV in Hubei Province of China, 668 serum samples collected from 14 pig-breeding farms were tested. We found that the PRRSV-positive rate was 5.24 % and that HP-PRRSV had become the dominant strain. To further investigate the genetic variation of PRRSV strains in this region, the complete gene sequences of nsp2, orf5, and orf7 from nine PRRSV strains collected during 2011-2012 were determined and compared with 33 known sequences. The results revealed that diverse HP-PRRSV strains are present in this region. An analysis of orf5 gene sequences showed that the strains collected during 2009-2010 formed a tightly clustered branch. When compared with the JXA1 strain, they had one mutation (V29 → A29) in a decoy epitope. Furthermore, we found that the number of potential N-glycosylation sites had apparently increased since 2006. These findings increase our knowledge of PRRSV epidemiology in Central China. [ABSTRACT FROM AUTHOR]

The genotypes of ten citrus tristeza virus (CTV) isolates from central China were determined by examining multiple molecular markers (MMMs) using 11 primer pairs. The results revealed that one isolate contained a single T30 genotype, two isolates contained a single VT genotype, and the other seven isolates were mixtures of two or more genotypes. Sequence analysis of amplified MMMs showed a high genetic diversity in Chinese CTV populations. The genotypes resembling T36, RB and B165 were identified from Chinese CTV isolates for the first time. Our results suggest that genotype assignment of CTV cannot be based solely on the amplification profiles of MMMs, and sequencing of MMMs is required. [ABSTRACT FROM AUTHOR]

A previous investigation showed that MX10 virus, recently isolated in China, belongs to the Oriental-Australian (O/A) genotype of Sindbis virus (SINV) (Wang Jinglin, 2011, ATMH). Similar to the MRE16 isolate, the prototype O/A genotype of SINV, two derivate viruses with obviously different plaque morphologies were derived from MX10 virus, which were accordingly denoted as MX10-LP and MX10-SP. MX10-LP virus exhibited higher neurovirulence in neonatal mice than MX10-SP virus. Analysis of the complete genome revealed seven nucleotide differences between MX10-LP and MX10-SP. Compared with MRE16 virus, MRE16SP virus has a deletion of 30 aa in the E2 gene (200-229), which has been shown to be the molecular basis for the different plaque morphology. However, the MX10-SP virus did not have the 30-amino-acid deletion in the E2 gene. These results demonstrate that the molecular basis for the different plaque morphology of MX10 virus, the first strain of the O/A genotype of SINV isolated from China, is different from that of the prototype MRE16 virus. [ABSTRACT FROM AUTHOR]

A 15-month boy with fatal hand, foot, and mouth disease (HFMD) exhibited atypical symptoms and progressed rapidly to death. An autopsy was performed the next day and tissue sections were stained for histopathological examination. His intestinal samples were tested for enterovirus 71 (EV71), and the whole-genome sequence of EV71 was analyzed. An autopsy revealed that the central nervous system, lungs, and gut displayed severe meningitis and brainstem encephalitis, remarkable pulmonary congestion, edema, moderate inflammatory infiltration, and hemorrhage as well as intestinal mucosal congestion, epithelial necrosis, thinning intestinal wall, and submucosal lymphoid follicular hyperplasia. The heart showed myocardial interstitial congestion, myocardial edema, and some inflammatory infiltrates. There were no significant alterations in the architecture of other organs. EV71 antigen and apoptotic cells were detected in brain, lung and intestine by immunohistochemical staining and TUNEL (TdT-mediated dUTP nick-end labeling) respectively. Intestinal contents and intestinal autopsy samples of this case were positive for EV71, and the EV71 strain was classified as subgenogroup C4. In China, the severe forms of HFMD were mostly caused by EV71 subgenogroup C4 infection. Severe intestinal damages may relate to EV71 subgenogroup C4 infection. Thus, children with severe EV71 HFMD may have serious pathological changes in their central nervous system, lungs, and gut. Physicians should pay special attention to infants with atypical symptoms, particularly in EV71 epidemic areas for early diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Polymerase chain reaction (PCR) and sequencing are useful for species identification of Trichinella spp., especially when their morphological characteristics useful for identifying taxa are lacking. In the present study, nine Trichinella isolates from different provinces in mainland China were identified by the PCR-based method using the 5S ribosomal DNA intergene spacer region (5S ISR) and the mitochondrial large subunit ribosomal DNA genes as molecular markers. The results indicated that eight isolates originating from domestic pigs and one isolate originating from civet cat ( Paguma larvata) showed identical DNA banding pattern to Trichinella spiralis. Sequence analysis of the 5S ISR gene further confirmed that the nine Trichinella isolates were T. spiralis and revealed the intraspecies genetic variation within T. spiralis. [ABSTRACT FROM AUTHOR]

In this study, the prevalence and characteristics of hepatitis E virus (HEV) in pigs and the general population in the Yunnan province, China, were evaluated. Nine hundred sixty sera, 95 liver and 60 feces samples were randomly collected from pig farms and abattoirs, in addition 173 human sera were sampled in the provincial capital city for a serological survey and an RT-nPCR assay. The screening results showed that among 621 samples collected from five pig farms, the HEV-specific IgG positive rate ranged from 73.2% to 83.5%, and the overall seroprevalence was 78.9% (490/621). A further analysis revealed that the seroprevalence increased with age. The positive rate of human serum samples was 39.9% (69/173). HEV RNA was detected in five swine feces, six swine liver and one anti-HEV-IgM-positive human serum sample by RT-nPCR. Sequence and alignment of the 348-nt PCR-amplified products of 12 HEV strains identified nine distinct nucleotide sequences. Phylogenetic and molecular evolutionary analysis revealed that these nine sequences shared 84.2% to 100.0% nucleotide sequence identity with each other, with all isolates belonging to genotype 4 HEV and clustering with other Chinese swine and human HEV sequences determined earlier. This study results suggest that the prevalence of genotype 4 HEV is serious, both in pig herds and in the human population, and authorities should pay more attention to the prevalence of HEV in southwest China. [ABSTRACT FROM AUTHOR]

Timely identification of pandemic influenza threats depends on monitoring for highly pathogenic avian influenza viruses. We isolated highly pathogenic avian influenza A(H5N6) virus clade 2.3.4.4, genotype G1.1, in samples from a bird in southwest Russia. The virus has high homology to human H5N6 influenza strains isolated from southeast China. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) 1 and PRRSV 2 have coexisted in China for a very long time. In this study, the complete genomic characterization of a PRRSV 1 strain named KZ2018 was conducted. The results showed that it shared 88.6% identity with Lelystad virus and 81.9–90.8% identities with other Chinese PRRSV 1 strains. Further study showed that its nsp2 protein had a unique discontinuous 6-amino acid (aa) deletion (aa357-360+aa411+aa449). Additionally, its GP3 and GP4 contained a long continuous 18-aa deletion in their overlapped region, which has never been described in other Chinese PRRSV 1 isolates. Amino acid analysis of cell epitopes revealed that GP3 245-256 and GP4 57-68 were the most variable epitopes among different Chinese PRRSV 1 isolates. The results might enrich our knowledge of PRRSV 1 strains in China. • Chinese PRRSV 1 strain KZ2018 had a unique discontinuous 6-aa deletion in nsp2. • KZ2018 strain had the longest 18-aa deletion in overlapping region of GP3 and GP4. • GP3 245-256 and GP4 57-68 were most variable epitopes among Chinese PRRSV 1 strains. [ABSTRACT FROM AUTHOR]

Objective: We isolated and identified the genotypes and molecular characteristics of the imported B3 measles virus (MeV) in Fujian province in 2018. Methods: Throat swab specimens were collected from clinically diagnosed measles patients and tested for viral RNA, using the real-time reverse transcription-polymerase chain reaction after the RNA extraction. Reverse transcription-polymerase chain reaction method was undertaken to amplify the 634 nucleotide acids of 3-terminal of the nucleoprotein gene. A phylogenetic tree was constructed and similarities in homology assessed. Results: We successfully isolated and obtained two measles virus strains and eighteen viral nucleic acid sequences. The Fujian strains were clustered within the same genotype group of WHO genotype B3 reference strains. Compared to the major circulating measles strain genotype B3 in the world, two Fujian strains MV18-41 and MV18-42 showed 100.0 % nucleic acid homology to HongKong.CHN/35.18 strain which was isolated from Hong Kong in 2018. The remaining 16 Fujian strains showed the highest homology (99.9 % ) with the Mvs/Osaka.JPN/38.18/B3 strain isolated from Japan in 2018. Compared with other 23 WHO genotype reference strains, homology on both nucleotide and amino acid of the Fujian strain and the B1 genotype reference strain were the smallest, as 95.1 % -95.4 % and 95.3 % , respectively. The differences of homology between the Fujian strain and H1 genotype reference strain were the largest, as 88.7 % -89.0 % and 87.3 % , respectively. In addition, there were 13 mutation sites between the Fujian strain and the vaccine strain (Shanghai-191) at the 150 amino acid position of carboxy terminus on N protein, However, these sites did not cause functional changes in the protein region. Conclusions: In Fujian province, two strains of B3 genotype measles virus were obtained successfully, which were considered to be new genotype measles virus found in 2018. These findings showed it is necessary to strengthening the monitoring program on imported cases for better control and eliminate the measles virus.

Summary: Background: After an absence of 29 years, dengue virus type 3 (DENV-3) re-emerged in Guangzhou in 2009 and again in 2010. However, the geographical route by which the virus entered the city, and how it has changed genetically, remain unclear. Therefore, we carried out a comprehensive investigation into the molecular characteristics of the DENV-3 involved. Methods: The envelope (E) genes of viruses isolated from dengue patients during the 2009–2010 epidemics were sequenced and compared with previously published E gene sequences of global representative DENV-3 strains available in GenBank, including isolates circulating in other provinces of China. Results: A total of 13 isolates (seven from 2009 and six from 2010) were obtained from human serum samples. Phylogenetic analysis revealed that the isolates were grouped into three genotypes (I, III, and V) and then two clades within genotype III (genotype I from Indonesia, genotype III clade A from Côte d’Ivoire, genotype III clade B from Tanzania, and genotype V from Philippines). In addition, there were 1.3–9.0% and 0.5–3.9% differences in the nucleic and deduced amino acid sequences between the 2009 and 2010 strains, respectively. Conclusions: The DENV-3 viruses from the period 2009–2010 were not from the continuous spread of an epidemic strain or the re-emergence of the 2009 strains in the 2-year period. The introduction of different DENV-3 genotypes following more than one geographical route was an important contributing factor to the 2009–2010 dengue epidemics in Guangzhou. [ABSTRACT FROM AUTHOR]