Human respiratory syncytial virus subgroups A and B outbreak in a kindergarten in Zhejiang Province, China, 2023

BackgroundIn May–June 2023, an unprecedented outbreak of human respiratory syncytial virus (HRSV) infections occurred in a kindergarten, Zhejiang Province, China. National, provincial, and local public health officials investigated the cause of the outbreak and instituted actions to control its spread.MethodsWe interviewed patients with the respiratory symptoms by questionnaire. Respiratory samples were screened for six respiratory pathogens by real-time quantitative polymerase chain reaction (RT-PCR). The confirmed cases were further sequenced of G gene to confirm the HRSV genotype. A phylogenetic tree was reconstructed by maximum likelihood method.ResultsOf the 103 children in the kindergarten, 45 were classified as suspected cases, and 25 cases were confirmed by RT-PCR. All confirmed cases were identified from half of classes. 36% (9/25) were admitted to hospital, none died. The attack rate was 53.19%. The median ages of suspected and confirmed cases were 32.7 months and 35.8 months, respectively. Nine of 27 confirmed cases lived in one community. Only two-family clusters among 88 household contacts were HRSV positive. A total of 18 of the G gene were obtained from the confirmed cases. Phylogenetic analyses revealed that 16 of the sequences belonged to the HRSV B/BA9 genotype, and the other 2 sequences belonged to the HRSV A/ON1 genotype. The school were closed on June 9 and the outbreak ended on June 15.ConclusionThese findings suggest the need for an increased awareness of HRSV coinfections outbreak in the kindergarten, when HRSV resurges in the community after COVID-19 pandemic

An assembly sequence planning method based on composite algorithm

To solve the combination explosion problem and the blind searching problem in assembly sequence planning of complex products, an assembly sequence planning method based on composite algorithm is proposed. In the composite algorithm, a sufficient number of feasible assembly sequences are generated using formalization reasoning algorithm as the initial population of genetic algorithm. Then fuzzy knowledge of assembly is integrated into the planning process of genetic algorithm and ant algorithm to get the accurate solution. At last, an example is conducted to verify the feasibility of composite algorithm

Effect of food type on the bioaccumulation and depuration of cadmium in the pacific cupped oyster, Crassostrea gigas

Cadmium (Cd) is commonly detected in aquatic environment and can accumulate in maricultural organisms. Modification of the food may change the bio-kinetics of trace metals in organisms. The aim of this study was to understand the effects of food type on the uptake and elimination of Cd in different tissues of oyster Crassostrea gigas. Oyster groups feeding with different food types were exposed to 10 μg/L Cd for 28 days, and then followed by a depuration of 35 days. One group was added natural seawater rich in algae, the other three groups were fed once daily with Dicrateria inornata, Nitzschia closterium f.minutissima and mixed alga (Dicrateria inornata: Nitzschia closterium f.minutissima=1:1), respectively. Oysters were sampled for chemical analysis by inductively coupled plasma mass spectrometry (ICP-MS). The mean concentrations of Cd among different oyster tissue were followed the order as: digestive gland > mantle > adductor muscle. A two-compartment model was used to estimate Cd uptake rates (k1), depuration rates (k2), bioconcentration factor (BCF), and half-lives (t1/2) in the three tissues, showing k1 was considerately higher than k2, therefore, the organism have high ability to accumulate Cd. The k1 in the digestive gland was the highest, followed by mantle and adductor muscle, while the k2 in the mantle was the lowest. In the present study, the group fed with mixed algae showed the fastest depuration rate and the shortest t1/2 in the important edible part of the oysters (digestive gland), which helps to improve food safety

Suppressing artifacts in the total focusing method using the directivity of laser ultrasound

Based on a synthesized laser ultrasonic array, full matrix capture can be used to acquire data, which can then be post-processed using the total focusing method. However, this noncontact ultrasonic imaging technique has not been widely used because of the numerous artifacts in ultrasonic images and time-consuming data acquisition. To address these issues, this study proposes a post-processing algorithm, which uses the laser ultrasound directivity information to suppress the artifacts in the total focusing method’s images. In particular, a weight factor is defined using the directivity information. By multiplying the image intensity of the total focusing method with this factor, the algorithm uses not only the amplitude and phase information of laser ultrasound but also its directivity information. The experimental results indicate that four types of artifacts are suppressed. Because the grating lobe artifacts can be suppressed, a larger element spacing can be used to reduce the data acquisition time

Comparative analysis of sigma factors RpoS, FliA and RpoN in Edwardsiella tarda

Sigma factors are important regulators that bacteria employ to cope with environmental changes. Studies on the functions of sigma factors have uncovered their roles in many important cellular activities, such as growth, stress tolerance, motility, biofilm formation, and virulence. However, comparative analyses of sigma factors, which examine their common and unique features or elucidate their cross-regulatory relationships, have rarely been conducted for Edwardsiella tarda. Here, we characterized and compared motility and resistance to oxidative stress of E. tarda strains complemented with rpoS, fliA, and rpoN mutants. The results suggest that the sigma factors, FliA and RpoN, regulated motility, whereas RpoS exhibited no such function. RpoS and RpoN were essential for oxidative stress resistance, whereas FliA had no obvious impact under oxidative stress conditions. Furthermore, 2-dimensional gel electrophoresis (2-DE) based proteomics analysis, combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS/MS), revealed 12 differentially expressed protein spots that represented 11 proteins between the mutant and wild-type strains. Quantification of the expression of target genes by quantitative reverse transcription PCR (qRT-PCR) confirmed the results of our proteomics analysis. Collectively, these results suggest that these sigma factors are multi-functional mediators involved in controlling the expression of many metabolic pathway genes.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Human rabies in Zhejiang Province, China

Objectives: To explore the epidemiological characteristics of human rabies in Zhejiang Province, China. Methods: Descriptive and statistical analyses were performed using data collected through interview with human rabies cases or their relatives during 2007 to 2014. A standardized questionnaire was used to collect the data. Results: Two hundred and one cases of human rabies were diagnosed in Zhejiang Province between 2007 and 2014, with a gradually declining annual incidence. Of the rabies cases identified, 61.2% were aged 40–65 years, and the male to female ratio was 2.30:1; 63.7% of cases occurred in the summer and autumn. The two most reported occupations were farmer (69.2%) and rural laborer (15.4%). Wenzhou, Jinhua, and Huzhou were the three cities with the most reported cases. The majority of cases (92.8%) were attributed to canines, and 71.0% of animal vectors were household animals. Less than half of the cases (41.4%) sought wound treatment after exposure. Post-exposure passive immunization was given to 9.7% and active immunization to 2.3%. Cases with a wound on the head/face only had a significantly shorter incubation than those with wounds at other sites (p < 0.05); cases with a wound on the hand only had a significantly shorter incubation than those with a wound on the lower limb below the knee only (p < 0.001). Non-resident cases were significantly younger (p < 0.001) and had a shorter disease duration (p = 0.015) than locally resident cases. Conclusions: The majority of rabies cases occurred among 40–65-year-old male residents of northern, mid-west, and southeast Zhejiang Province. Further health education is needed to increase the coverage of post-exposure prophylaxis (PEP) in people exposed to possible rabid animals and rabies vaccine use in household animals

Comparison of Influenza Epidemiological and Virological Characteristics between Outpatients and Inpatients in Zhejiang Province, China, March 2011–June 2015

Given the rapid rate of global spread and consequently healthcare costs related to influenza, surveillance plays an important role in monitoring the emerging pandemics in China. However, the characteristics of influenza in Southeast of China haven’t been fully studied. Our study use the surveillance data collected from 16 sentinel hospitals across Zhejiang Province during March 2011 through June 2015, including the demographic information and respiratory specimens from influenza-like illness (ILI) patients and severe acute respiratory illness (SARI) patients. As analysis results, most SARI and ILI patients were in the age group of 0–4 years old (62.38% of ILI and 71.54% of SARI). The respiratory specimens have statistically significantly higher positive rate for influenza among ILI patients than that among SARI patients (p &lt; 0.001). The comparison between ILI patients and SARI patients shows no statistically significantly difference in detecting influenza virus type and influenza A virus subtype. The SARI and ILI patients were found to be positively correlated for overall positive rate (r = 0.63, p &lt; 0.001), the weekly percentage of A(H1N1)pdm09 (r = 0.51, p &lt; 0.001), influenza B virus (r = 0.17, p = 0.013), and A/H3N2 (r = 0.43, p &lt; 0.001) among all the positive numbers. Our study demonstrated that the activities of influenza virus, including its subtypes, had a similar temporal pattern between ILI and SARI cases