Objective:To compare the enrichment effects of ultrafiltration, polyethylene glycol (PEG) precipitation, aluminum salt precipitation, and anionic membrane adsorption-elution on viruses in drinking water.Methods:Using phage MS2 as the target virus, three different concentrations of drinking water samples were prepared, and the samples were enriched by ultrafiltration 1, ultrafiltration 2, PEG precipitation, aluminum salt precipitation, and anionic membrane adsorption-elution method, respectively. Real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was used to quantify MS2 nucleic acid in pre and post concentrated samples and the recovery rates of MS2 in samples with high, medium and low concentrations were compared among the five methods.Results:Comparing the MS2 enrichment recovery rates of individual enrichment method in water samples of different concentrations, ultrafiltration method 1, PEG precipitation method, aluminum salt precipitation method, and membrane adsorption-elution method were not affected by the sample concentration, and the differences of the recovery rates for the three concentration water samples among the four methods were not statistically significant ( P>0.05). The MS2 enrichment recovery rates of the five enrichment methods were significantly different in all concentration samples ( P<0.05). The recovery rates of ultrafiltration method 1 were higher in all three concentration samples, followed by aluminum salt precipitation and anionic membrane adsorption-elution, PEG precipitation were higher in high concentration samples, but lower in low and medium concentration samples, and the recovery rates of ultrafiltration method 2 were the lowest in all three concentration samples. Comparing the Ct values of MS2 in the enriched samples by five methods, the Ct values of ultrafiltration method 1 were the smallest in the three concentration water samples. There was no statistically significant difference in MS2 Ct values among the five enrichment methods in the medium and high concentration water samples ( P>0.05). In low concentration simulated water samples, only the difference of MS2 Ct value between ultrafiltration method 1 and ultrafiltration method 2 was statistically significant ( Z=16.000, P=0.016). Conclusions:Considering the operation simplicity, operation time and virus recovery rate after enrichment, ultrafiltration was the most effective method for virus enrichment in drinking water.

Debates persist regarding the efficacy and safety of azvudine, particularly its real-world outcomes. This study involved patients aged ≥60 years who were admitted to 25 hospitals in mainland China with confirmed SARS-CoV-2 infection between December 1, 2022, and February 28, 2023. Efficacy outcomes were all-cause mortality during hospitalization, the proportion of patients discharged with recovery, time to nucleic acid-negative conversion (T _NANC), time to symptom improvement (T _SI), and time of hospital stay (T _HS). Safety was also assessed. Among the 5884 participants identified, 1999 received azvudine, and 1999 matched controls were included after exclusion and propensity score matching. Azvudine recipients exhibited lower all-cause mortality compared with controls in the overall population (13.3% vs. 17.1%, RR, 0.78; 95% CI, 0.67-0.90; P = 0.001) and in the severe subgroup (25.7% vs. 33.7%; RR, 0.76; 95% CI, 0.66-0.88; P < 0.001). A higher proportion of patients discharged with recovery, and a shorter T _NANC were associated with azvudine recipients, especially in the severe subgroup. The incidence of adverse events in azvudine recipients was comparable to that in the control group (2.3% vs. 1.7%, P = 0.170). In conclusion, azvudine showed efficacy and safety in older patients hospitalized with COVID-19 during the SARS-CoV-2 omicron wave in China.

Objective:To compare the enrichment effects of ultrafiltration, polyethylene glycol (PEG) precipitation, aluminum salt precipitation, and anionic membrane adsorption-elution on viruses in drinking water.Methods:Using phage MS2 as the target virus, three different concentrations of drinking water samples were prepared, and the samples were enriched by ultrafiltration 1, ultrafiltration 2, PEG precipitation, aluminum salt precipitation, and anionic membrane adsorption-elution method, respectively. Real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was used to quantify MS2 nucleic acid in pre and post concentrated samples and the recovery rates of MS2 in samples with high, medium and low concentrations were compared among the five methods.Results:Comparing the MS2 enrichment recovery rates of individual enrichment method in water samples of different concentrations, ultrafiltration method 1, PEG precipitation method, aluminum salt precipitation method, and membrane adsorption-elution method were not affected by the sample concentration, and the differences of the recovery rates for the three concentration water samples among the four methods were not statistically significant ( P>0.05). The MS2 enrichment recovery rates of the five enrichment methods were significantly different in all concentration samples ( P<0.05). The recovery rates of ultrafiltration method 1 were higher in all three concentration samples, followed by aluminum salt precipitation and anionic membrane adsorption-elution, PEG precipitation were higher in high concentration samples, but lower in low and medium concentration samples, and the recovery rates of ultrafiltration method 2 were the lowest in all three concentration samples. Comparing the Ct values of MS2 in the enriched samples by five methods, the Ct values of ultrafiltration method 1 were the smallest in the three concentration water samples. There was no statistically significant difference in MS2 Ct values among the five enrichment methods in the medium and high concentration water samples ( P>0.05). In low concentration simulated water samples, only the difference of MS2 Ct value between ultrafiltration method 1 and ultrafiltration method 2 was statistically significant ( Z=16.000, P=0.016). Conclusions:Considering the operation simplicity, operation time and virus recovery rate after enrichment, ultrafiltration was the most effective method for virus enrichment in drinking water.

Objective:To understand the gene characteristics of Sapovirus from diarrhea cases in diarrhoeal disease clinics in Beijing.Methods:In 2019, stool samples were collected from diarrhea cases in diarrhoeal disease clinics in Beijing. The samples were used for the detection of nucleic acid of Sapovirus with real-time RT-PCR. Different RT-PCR methods were used for the partial gene segment amplification in the capsid protein VP1 region and the polymerase RdRp region, and sequencing was conducted for amplified positive products. The sequences were aligned with software BioEdit 7.0.9.0 and analyzed with software Mega 6.06.Results:The overall detection rate of Sapovirus was 2.89% (44/1 522), the detection rate in children under 5 years old was 3.34% (18/539) and 2.64% (26/983) in children aged ≥5 years. The capsid protein VP1 region was sequenced in 23 strains belonging to 8 genotypes (GⅠ.2 had 6 strains, GⅠ.1 and GⅡ.3 had 5 strains, respectively, GⅠ.3 and GⅡ.5 had 2 strains, respectively, GⅠ.5, GⅡ.1 and GⅣ.1 had 1 strain, respectively). A total of 16 strains were detected in the cases aged ≥5 years, and the proportion of GⅠ.2 was highest (37.50%, 6/16), and 7 strains were detected in the cases under 5 years old, the proportions of GⅠ.1 and GⅡ.3 were highest (both 42.86%, 3/7); The internal similarity of each genotype was 95.5%-100.0%, and the similarity with the 51 reference strains of human or sewage sources in different years and different countries was 92.2%-100.0%. The polymerase RdRp region was sequenced in 25 strains belonging to 8 genotypes (GⅡ.P3 had 9 strains, GⅠ.P3 had 4 strains, GⅠ.P1, GⅠ.P2 and GⅡ.P1 had 3 strains, respectively, GⅠ.P5, GⅡ.P5 and GⅣ.P1 had 1 strain, respectively). Fifteen strains were detected in the cases aged ≥5 years, and GⅡ.P3 had the highest proportion (40.00%, 6/15). Ten strains were detected in the cases under 5 years old, and the proportions of GⅠ. P1, GⅡ.P1 and GⅡ.P3 were highest (all 30.00%, 3/10); The internal similarity of each genotype was 94.0%-100.0%, and the similarity with the 39 reference strains of human or sewage sources in different years and different countries was 90.2%-99.1%.Conclusions:Sapovirus is one of the pathogens among diarrhea cases in Beijing. The main genome is GⅠ and GⅡ, and the genotypes are diverse and dispersed. The main genotypes of diarrhea cases in people aged ≥5 years and less than 5 years are different.

Objective:To explore the safety of nirmatrelvir/ritonavir (Paxlovid) in the treatment of coronavirus disease 2019 (COVID-19).Methods:Medical records of adult patients with COVID-19 who were hospitalized and treated with Paxlovid in Beijing Ditan Hospital, Capital Medical University between March 23 and May 31, 2022 were collected through the hospital electronic medical record system. The occurrence (time of occurrence, clinical manifestations, severity, etc.) and outcomes of adverse reactions were analyzed retrospectively and the clinical characteristics of patients with or without adverse reactions were compared. Paxlovid was administered orally with nirmatrelvir 300 mg and ritonavir 100 mg every 12 hours for 5 consecutive days.Results:Three hundred and sixty-four patients were entered in the analysis, including 200 males (54.9%) and 164 females (45.1%), with a median age of 60 (19, 92) years. The incidence of adverse reactions of Paxlovid was 13.2% (48/364), and the adverse reactions occurred 1 to 7 days after taking Paxlovid. Among the 48 patients, 37 patients had digestive system symptoms (mainly manifested as diarrhea in 17 patients, bitter mouth in 14 patients, etc.), 7 patients had nervous system symptoms (dizziness in 5 patients, headache in 2 patients), 4 patients had respiratory system symptoms (pharyngalgia in 3 patients, pharyngeal itching in 1 patient), 2 patients had kidney injury, 1 patient had elevated blood uric acid, 1 patient had myalgia, and 1 patient had rash. Of them, 2 patients had digestive and neurological symptoms at the same time, 1 patient had digestive and respiratory symptoms at the same time, and 1 patient had digestive, neurological, and respiratory symptoms at the same time. The severity of adverse reactions was grade 1 in 33 patients (68.8%) and grade 2 in 15 patients (31.2%), and no serious adverse reactions of grade 3 and above occurred. All patients completed 5 days of treatment except 1 patient who discontinued the drug because of intolerance to grade 2 digestive symptoms (nausea and bitter mouth). There were no significant differences in gender, age, body mass index, smoking status, underlying diseases, and COVID-19 clinical classification between the patients with and without adverse reactions (all P>0.05). Conclusions:Paxlovid has a good safety in the treatment of COVID-19. The main adverse reaction is digestive system symptoms, mainly diarrhea and bitter mouth. Most of the symptoms are mild and the patient′s tolerance is good.

Objective:To explore the safety of nirmatrelvir/ritonavir (Paxlovid) in the treatment of coronavirus disease 2019 (COVID-19).Methods:Medical records of adult patients with COVID-19 who were hospitalized and treated with Paxlovid in Beijing Ditan Hospital, Capital Medical University between March 23 and May 31, 2022 were collected through the hospital electronic medical record system. The occurrence (time of occurrence, clinical manifestations, severity, etc.) and outcomes of adverse reactions were analyzed retrospectively and the clinical characteristics of patients with or without adverse reactions were compared. Paxlovid was administered orally with nirmatrelvir 300 mg and ritonavir 100 mg every 12 hours for 5 consecutive days.Results:Three hundred and sixty-four patients were entered in the analysis, including 200 males (54.9%) and 164 females (45.1%), with a median age of 60 (19, 92) years. The incidence of adverse reactions of Paxlovid was 13.2% (48/364), and the adverse reactions occurred 1 to 7 days after taking Paxlovid. Among the 48 patients, 37 patients had digestive system symptoms (mainly manifested as diarrhea in 17 patients, bitter mouth in 14 patients, etc.), 7 patients had nervous system symptoms (dizziness in 5 patients, headache in 2 patients), 4 patients had respiratory system symptoms (pharyngalgia in 3 patients, pharyngeal itching in 1 patient), 2 patients had kidney injury, 1 patient had elevated blood uric acid, 1 patient had myalgia, and 1 patient had rash. Of them, 2 patients had digestive and neurological symptoms at the same time, 1 patient had digestive and respiratory symptoms at the same time, and 1 patient had digestive, neurological, and respiratory symptoms at the same time. The severity of adverse reactions was grade 1 in 33 patients (68.8%) and grade 2 in 15 patients (31.2%), and no serious adverse reactions of grade 3 and above occurred. All patients completed 5 days of treatment except 1 patient who discontinued the drug because of intolerance to grade 2 digestive symptoms (nausea and bitter mouth). There were no significant differences in gender, age, body mass index, smoking status, underlying diseases, and COVID-19 clinical classification between the patients with and without adverse reactions (all P>0.05). Conclusions:Paxlovid has a good safety in the treatment of COVID-19. The main adverse reaction is digestive system symptoms, mainly diarrhea and bitter mouth. Most of the symptoms are mild and the patient′s tolerance is good.

Objective: To understand the prevalence and associated factors of school bullying among primary and secondary school students in Haidian District, and to provide scientific basis for intervention plan. Methods: From September to October 2021, 1 906 primary and secondary school students in Haidian District were selected by stratified cluster random sampling for electronic questionnaire survey,an electronic questionnaire survey was conducted on students by using the questionnaire of the Student Health Status and Influencing Factors Questionnaire. Results: The prevalence of campus bullying among primary and secondary school students in Haidian District was 4.3%, of which primary school (7.6%) > junior middle school (4.1%) > vocational high school (2.5%) > senior high school (1.9%) ( χ 2=23.49, P ＜0.01), boys (5.5%) were more than girls (3.0%) ( χ 2=7.44, P ＜ 0.01 ), students from abnormal families (6.9%) were higher than students from normal families (3.9%) ( χ 2=4.24, P =0.04). Multivariate Logistic regression analysis showed that students in primary school had a higher risk of being bullied in school ( OR =2.13). Abnormal family ( OR = 1.07 ), smoking experience ( OR =2.28), experience of being beaten and scolded by parents( OR =2.49) and fighting behavior ( OR =1.84) were positively correlated with school bullying ( P <0.05). Conclusion Campus bullying is prevalent in primary and secondary schools in Haidian District, which warrents further attention of schools and education departments. Family school partnership and targeted prevention and intervention measures for key populations are expected.

Objective:To provide evidence for clinical diagnosis, prevention and control of group A rotavirus (RVA) diarrhea, the clinical characteristics of RVA diarrhea in children in Beijing from 2011 to 2018 were analyzed.Methods:From January 2011 to December 2018, 4 819 stool samples from children under 5 years old with diarrhea were collected monthly from 3 hospitals in Beijing. General information, clinical characteristics and other information of children were collected. RVA was detected by enzyme-linked immunosorbent assay (ELISA), genotype was identified by multiple semi-nested RT-PCR. The Vesikari clinical severity score was used to define the severity of diarrhea in children. Dichotomous unconditional logistic regression was used to analyze clinical symptoms and other differences between RVA positive and negative cases. Chi-square and Fisher direct probability tests were used to compare the composition among different groups.Results:A total of 4 819 fecal samples were collected, 953 were positive for RVA, the positive detection rate was 19.78%. The positive rate of RVA was high in the younger age group, and the incidence was high in winter and spring. RVA-positive children had more risk on diarrhea ≥5 times a day, vomiting symptoms, fever, mild dehydration, and Vesikari score ≥11. The positive rate of RVA in watery stool samples (26.13%, 214/819) and infectious diarrhea cases (42.20%, 265/628) was the highest respectively. There were no significant differences in clinical symptoms, clinical diagnoses and fecal traits among children with different RVA genotypes.Conclusions:The clinical symptoms of RVA diarrhea were severe in children. RVA genotype did not affect the clinical symptoms. Stool traits (watery stools) and Vesikari score can assist physicians in diagnosing RVA diarrhea.

Norovirus are now recognized as one of the main pathogens causing acute gastroenteritis in both developed and developing countries. However, norovirus are easily mutated and recombined, and have many genotypes. In early studies, norovirus were amplified and identified by amino acid sequence of VP1 region. It was found that norovirus were easily mutated and recombined in or near the overlapping regions of polymerase and capsid. A two regions genotyping method was positively proposed internationally. Depending on the 2 times standard deviation standard method for two regions identification, norovirus polymerase regions can be divided into 10 gene groups and 76 genotypes including 2 tentative gene groups and 16 tentative genotypes. The VP1 region can be divided into 12 gene groups and 53 genotypes including 2 tentative gene groups and 5 tentative genotypes. However, the tentative gene groups and genotypes need to be further identified and reclassified. In this article, characteristics of norovirus sequences, principles of different genotyping methods, methods of sequence amplification, on-line genotyping tools and the latest studies in norovirus genotypes are reviewed and introduced.

Objective:To investigate the contamination of ball lettuce sold by norovirus and rotavirus in Beijing.Methods:From November 2015 to October 2016, 54 samples were collected at a market stall in Beijing. The potentially existing viruses were eluted and concentrated from the ball lettuce leaves using centrifugation and direct methods corresponding to three kinds of eluants. Norovirus and rotavirus were detected by real time RT-PCR. The partial VP1 gene of norovirus was amplified by semi-nested RT-PCR. The PCR product was sequenced directly, the sequence alignment was performed using the BioEdit 7.0.9.0 software, the phylogenetic tree was constructed with the MEGA 6.06 software.Results:Among 54 pieces of ball lettuce, rotavirus was detected negative, and the detection rate of norovirus was 11.11% (6/54). Of these NoV-positive specimens, 3 (50.0%) were NoV GII, 1 (16.7%) was NoV GI, and 2 (33.33%) were a mix of NoV GI and GII, The detection rates in spring, summer, autumn and winter were 8.3% (1/12), 0.0% (0/8), 28.6% (4/14) and 5.0% (1/20), respectively. One strain was sequenced successfully and identified as GII.3 genotype. The strain shares 100.0% nucleotide identity with strain KY348698 isolated from human in Guangdong in 2014.Conclusions:Human norovirus contamination existed in some ball lettuce sold in Beijing, eating raw unwashed ball lettuce may indicate a risk of viral acute gastroenteritis.