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To analyze the epidemiological characteristics of group A rotavirus (RVA) diarrhea in Beijing between 2019 and 2022 and evaluate the effectiveness of the RV5 vaccine. Stool specimens were collected from patients with acute diarrhea, and RVA was detected and genotyped. The whole genome of RVA was sequenced by fragment amplification and Sanger sequencing. Phylogenetic trees were constructed using Bayesian and maximum likelihood methods. Descriptive epidemiological methods were used to analyze the characteristics of RVA diarrhea. Test‐negative design was used to evaluate the vaccine effectiveness (VE) of the RV5. Compared with 2011–2018, RVA‐positive rates in patients with acute diarrhea under 5 years of age and adults decreased significantly between 2019 and 2022, to 9.45% (249/634) and 3.66% (220/6016), respectively. The predominant genotype of RVA had changed from G9‐VIP[8]‐III between 2019 and 2021 to G8‐VP[8]‐III in 2022, and P[8] sequences from G8‐VP[8]‐III strains formed a new branch called P[8]‐IIIb. The complete genotype of G8‐VP[8]‐III was G8‐P[8]‐I2‐R2‐C2‐M2‐A2‐N2‐T2‐E2‐H2. The VE of 3 doses of RV5 was 90.4% (95% CI: 28.8%–98.7%) against RVA diarrhea. The prevalence of RVA decreased in Beijing between 2019 and 2022, and the predominant genotype changed to G8P[8], which may be related to RV5 vaccination. Continuous surveillance is necessary to evaluate vaccine effectiveness and improve vaccine design. [ABSTRACT FROM AUTHOR]

Mpox is still spreading globally and is mostly reported to be transmitted by skin and mucosal contact. However, transmission through contact with fomites, contaminated objects, or surfaces has been reported in general population. Evaluation of the stability of mpox virus (MPXV) on different surfaces is important to minimize mpox transmission. In the study, the stability of MPXV on different kinds of commonly contacted surfaces was determined. MPXV was observed to have a surface‐dependent stability pattern. Viable virus was detected on both glass and stainless steel for up to 5 days, and on plastic surfaces for up to 3 days. In contrast, no viable MPXV was detected on wooden board and cardboard, which are porous and water‐absorbent surfaces, after 1 and 2 days of incubation, respectively. In addition, MPXV nucleic acids were more stable and showed better correlation with viral titers on stainless steel, plastic, and glass. The results indicate that fomite transmission of MPXV is plausible. Moreover, the stability of MPXV was highly surface‐dependent and more stable on smooth surfaces, which could provide more information for minimizing the transmission of mpox and emphasize the significance of environmental disinfection in mpox prevention and control. [ABSTRACT FROM AUTHOR]

The transmissibility is a crucial feature for norovirus, yet its quantitative estimation has been limited. Our objective was to estimate the basic reproduction number (R0) of norovirus and investigate its variation characteristics. Norovirus outbreaks reported from September 2016 to August 2021 in Beijing were analyzed. The susceptible‐infected‐removed compartment model was established to estimate R0. Linear regression models and logistic regression models were used to explore the factors affecting the transmissibility of norovirus. The overall median R0 of norovirus was estimated as 2.1 (interquartile range [IQR] 1.8–2.5), with 650 norovirus outbreaks. The transmissibility of norovirus varied by year, outbreak setting and genotype. The R0 of norovirus during September 2019 to August 2020 (median 2.1, IQR 1.8–2.4) and September 2020 to August 2021 (median 2.0, IQR 1.7–2.3) was lower than that of September 2016 to August 2017 (median 2.3, IQR 1.8–2.7) (β = 0.94, p = 0.05; β = 0.93, p = 0.008). The R0 of norovirus for all other settings was lower than that for kindergarten (median 2.4, IQR 2.0–2.9) (primary school: median 2.0, IQR 1.7–2.4, β = 0.94, p = 0.001; secondary school: median 1.7, IQR 1.5–2.0, β = 0.87, p < 0.001; college: median 1.7, IQR 1.5–1.8, β = 0.89, p = 0.03; other closed settings: median 1.8, IQR 1.5–2.0, β = 0.90, p = 0.004). GⅡ.2[P16] outbreaks had a median R0 of 2.2 (IQR 1.8–2.7), which was higher than that for GⅡ.6[P7] outbreaks (median 1.8, IQR: 1.8–2.0, odds ratio = 0.19, p = 0.03; GⅡ.2[P16] as reference) and mixed‐genotype outbreaks (median 1.7, IQR: 1.5–1.8, β = 0.92, p = 0.02; mixed‐genotype as reference). In kindergartens and primary schools, norovirus shows increased transmissibility, emphasizing the vulnerable population and high‐risk settings. Furthermore, the transmissibility of norovirus may change over time and with virus evolution, necessitating additional research to uncover the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Coxsackievirus A16 (CV‐A16) is a significant pathogen responsible for causing hand foot and mouth disease (HFMD) and herpangina (HA). This study aimed to investigate the recent evolution and spread of CV‐A16 by monitoring HFMD and HA cases in 29 hospitals across 16 districts in Beijing from 2019 to 2021. The first five cases of HFMD and the first five cases of HA each month in each hospital were included in the study. Real‐time reverse transcription polymerase chain reaction was used to identify CV‐A16, CV‐A6, and EV‐A71. From each district, two to four CV‐A16 positive samples with a relatively long sampling time interval every month were selected for sequencing. A total of 3344 HFMD cases and 2704 HA cases were enrolled in this study, with 76.0% (2541/3344) of HFMD and 45.4% (1227/2704) of HA cases confirmed to be infected by enterovirus. Among the EV‐positive samples, CV‐A16 virus was detected in 33.61% (854/2541) of HFMD cases and 13.4% (165/1227) of HA cases, with the predominant cluster being B1a. Both B1a and B1b had a co‐circulation of local and imported strains, with different origin time (1993 vs. 1995), different global distribution (14 countries vs. 10 countries), and different transmission centers but mainly distributed in the southern and eastern regions of Beijing. Strengthening surveillance of HFMD in southern and eastern regions will improve the prevention and control efficiency of enterovirus infections. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 is still spreading globally. Studies have reported the stability of SARS‐CoV‐2 in aerosols and on surfaces under different conditions. However, studies on the stability of SARS‐CoV‐2 and viral nucleic acids on common food and packaging material surfaces are insufficient. The study evaluated the stability of SARS‐CoV‐2 using TCID50 assays and the persistence of SARS‐CoV‐2 nucleic acids using droplet digital polymerase chain reaction on various food and packaging material surfaces. Viral nucleic acids were stable on food and material surfaces under different conditions. The viability of SARS‐CoV‐2 varied among different surfaces. SARS‐CoV‐2 was inactivated on most food and packaging material surfaces within 1 day at room temperature but was more stable at lower temperatures. Viruses survived for at least 1 week on pork and plastic at 4°C, while no viable viruses were detected on hairtail, orange, or carton after 3 days. There were viable viruses and a slight titer decrease after 8 weeks on pork and plastic, but titers decreased rapidly on hairtail and carton at –20°C. These results highlight the need for targeted preventive and disinfection measures based on different types of foods, packaging materials, and environmental conditions, particularly in the cold‐chain food trade, to combat the ongoing pandemic. [ABSTRACT FROM AUTHOR]

Different variants of severe acute respiratory syndrome coronavirus 2 have been discovered globally. At present, the Omicron variant has been extensively circulated worldwide. There have been several outbreaks of the Omicron variant in China. Here, we investigated the epidemiologic, genetic characteristics, and origin‐tracing data of the outbreaks of COVID‐19 in Beijing from January to September 2022. During this time, 19 outbreaks occurred in Beijing, with the infected cases ranging from 2 to 2230. Two concern variants were detected, with eight genotypes. Based on origin tracing analysis, two outbreaks were from the cold‐chain transmission and three from items contaminated by humans. Imported cases have caused other outbreaks. Our study provided a detailed analysis of Beijing's outbreaks and valuable information to control the outbreak's spread. [ABSTRACT FROM AUTHOR]

Background: Few studies have reported on the seroprevalence of antibodies against avian influenza A (H9N2) virus and the incidence of these infections in the northern China and among swine workers. Methods: We conducted a serological cohort study among people working with poultry or swine or the general population in Beijing, China. It comprised four cross‐sectional serological surveys in November 2013, April 2014, April 2015, and April 2016. Blood samples collected from the participants were tested for anti‐H9N2 antibodies using a hemagglutination‐inhibition (HI) assay. Multivariable Poisson regression model was then used to compare the person‐month incidence rates for H9N2 viral infections among the three groups, assessed by incidence rate ratio (IRR). Results: In the four cross‐sectional surveys, the highest seroprevalence of anti‐H9N2 antibodies (HI titer ≥ 80) was recorded in the poultry workers (2.77%, 19/685) in April 2016, while the lowest was recorded in the general population (0.09%, 1/1135) in April 2015. The highest incidence density rate for H9N2 infections across the whole study period was recorded among the poultry workers (3.75/1000 person‐months), followed by the swine workers (1.94/1000 person‐months) and the general population (1.78/1000 person‐months). Multivariable analysis showed that the poultry workers were at higher risk (IRR: 2.42, 95% CI: 1.07‐5.48; P = 0.034) of contracting H9N2 virus than the general population. Conclusions: Although the seroprevalence of H9N2 antibodies was low in Beijing, the poultry workers were at higher risk of contracting H9N2 viral infections than the general population. Closer monitoring and strengthened protection measures for poultry workers are warranted. [ABSTRACT FROM AUTHOR]

Background Severe acute respiratory infection (SARI) threatens human health and even survival, causing a huge number of hospitalized patients every year. However, as one of the most common respiratory viruses circulated worldwide, the epidemiological and phylogenetic characteristics of human parainfluenza virus (HPIV) in these cases were not well known. Objectives To reveal the epidemiological features of HPIV infection in SARIs in Beijing area from September 2014 to August 2016. Methods A total of 1229 SARI cases in Beijing area were enrolled, investigated, sampled, and tested by multiplex real-time PCR to identify HPIVs and other common respiratory viruses. Eighteen HPIV-3 viruses isolated from all HPIV-positive samples in these SARI cases were sequenced and analyzed. Results Among all enrolled cases, 0.81%, 0.73%, 4.48%, and 0.57% were positive for HPIV-1 to HPIV-4, respectively. The highest yield rate of HPIV infection occurred in children under 5 years old (9.07%), followed by the patients over 60 years old (6.02%). The phylogenetic information of HPIV-3 showed that all viruses belonged to Cluster C3a. Conclusions Besides the young children, the elders older than 60 years also showed a relatively high infection rate of HPIVs, which should be given comparable attentions. Moreover, the HPIV-3 circulating in China undergoes continued evolution, suggesting the potential risk of evolved HPIV infection should not be overlooked. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Yang et al. (2011) Seroprevalence of pandemic (H1N1) 2009 influenza and effectiveness of 2010/2011 influenza vaccine during 2010/2011 season in Beijing, China. Influenza and Other Respiratory Viruses 6(6), 381-388. Background In the post-pandemic period, pandemic (H1N1) 2009 virus was expected to circulate seasonally and was introduced into trivalent influenza vaccine during 2010/2011 season in the Northern Hemisphere. Objectives The aim of this study was to examine the evolution of herd immunity against pandemic (H1N1) 2009 virus in Beijing, China, during 2010/2011 season and effectiveness of the 2010/2011 trivalent vaccine. Methods Two serological surveys were conducted before and after 2010/2011 season in Beijing. A case-control study was used to investigate vaccine effectiveness against influenza-like illness (ILI) and lower respiratory tract infection (LRI). Results A total of 4509 and 4543 subjects participated in the pre- and post-season surveys, respectively. The standardized seroprevalence of pandemic (H1N1) 2009 influenza increased from 22·1% pre-season to 24·3% post-season ( P < 0·001). Significant elevation in seroprevalence appeared in the ≥60 years age-group ( P < 0·001), but not in others. The 2010/2011 trivalent vaccine contributed to the higher post-seasonal seroprevalence in unvaccinated individuals ( P = 0·024), but not in those vaccinated with monovalent pandemic vaccine ( P = 0·205), as well as in those without prior immunity versus those with immunity. The adjusted effectiveness of the 2010/2011 trivalent vaccine was 79% protection against ILI (95% CI, 61-89%) and 95% against LRI (95% CI: 59-99%). Conclusions A slight increase in herd immunity against pandemic (H1N1) 2009 influenza was observed in Beijing, China, during the 2010/2011 season. Prior vaccination and immunity had a suppressive impact on immune response toward this novel influenza virus, elicited by 2010/2011 trivalent vaccine. This trivalent vaccine conferred good protection against ILI and LRI. [ABSTRACT FROM AUTHOR]