Objective To test the anti-virus effect of inner silvered fiber and the influencing factors. Methods Under the given condition, the inactivation tests were conducted with the inner silvered fiber and virus suspension in which the polioviruses were used as the experimental subjects and HeLa Cells as the host cells. TCID50 was calculated before and after the inactivation in order to determine the virus-killing rate. Results The virus-killing rates of inner silvered fiber, exposed to the fluorescent lamp light at 37 ℃, for 5, 10, 30 and 60 minutes, were 73.10%, 96.84%, 99.99% and greater than 99.99% respectively, whereas in the dark, 37 ℃ for 30 minutes, the virus-killing rates was 78.47%. Conclusion Inner silvered fiber has a good efficiency of anti-virus.

A total of 100 HIN1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang,Hubei and Guangdong between June and November 2009,were provided by local CDC laboratories.After MDCK cell culture,57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing.A total of 39 HA sequences,52 NA sequences,36 PB2 sequences,31 PB1 sequences,40 PA sequences,48 NP sequences,51 MP sequences and 36 NS sequences were obtained,including 20 whole genome sequences.Sequence comparison revealed they shared a high degree of homology (96％～99％) with known epidemic strains (A/Califomia/04/2009(H1N1).Phylogenetic analysis showed that although the sequences were highly conserved,they clustered into a small number of groups with only a few distinct strains.Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences:A/Hubei/86/2009 PKVRDQEG→PKVRDQEA,A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER,A/Hubei/75/2009PKVRDQEG→PKVRDQGG,the A/Hubei/75/2009 was isolated from an acute case,while the other two were from patients with mild symptoms.Other key sites such as 119,274,292 and 294 amino acids of NA protein,627 of PB2 protein were conserved.Meanwhile,all the M2 protein sequences possessed the Ser32Asn mutation,suggesting that these viruses were resistant to adamantanes.Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.

Objective To investigate the impact of pooling of inactivated samples on testing results of nucleic acid detection of SARS-CoV-2, and to provide a scientific detection scheme for the SARS-CoV-2 nucleic acid screening of large population samples. Methods The SARS-CoV-2 positive throat swab samples and the negative throat swab samples were inactivated at 56°C for 30 minutes, and mixed according to the ratio of positive samples to negative samples at 1:4, 1:9, and 1:19, respectively. Real-time fluorescent RT-PCR technology was used to detect the ORF-lab and N genes in the original solution and mixed solution. Results The nucleic acid test results of the 20 groups of inactivated samples were all positive. The nucleic acid test results of the 1:5 mixture and the 1:10 mixture were also positive. One group of samples of the 1:20 mixture was negative for ORF-lab and positive for the N gene. The Ct values of nucleic acid detection among all groups were significantly correlated. There was no statistically significant difference in the positive rate between different sample groups. Compared with the original solution, the Ct values of the ORF-lab gene of 1:5 mixture, 1:10 mixture, and 1:20 mixture samples increased by 1.73, 2.86, and 4.05, respectively, while the Ct values of the N gene of 1:5 mixture, 1:10 mixture and 1:20 mixture samples increased by 1.69, 2.79, and 3.25, respectively. Conclusion When conducting nucleic acid screening for SARS-CoV-2 in large population samples, a mixed test of less than 10 inactivated samples would not affect the qualitative results in most cases, but the results of weak positive samples may be affected.

Objective:To survey and supervise the risk of infection control and radiation safety in the radiological diagnostic workplace for COVID-19, and provide data support for the safety protection of radiographers and related staff.Methods:4 emergency hospitals for COVID-19 including 2 makeshift hospitals, module hospital and brick pattern hospital in Hubei province were performed for testing and evaluation of imaging performance and radiological protection for the 8 new installed CT scanners and places according to the national standards of WS 519-2019 and GBZ 130-2013. The infection control safety factors such as the layout of the equipment room were monitored and investigated. Two COVID-19 designated hospitals including general hospital and infectious disease specialized hospital were selected to carry out field investigation and sampling of environmental biological samples for 4 CT rooms. Then the samples were detected for the nucleic acid of novel coronavirus. The results of radiodiagnostic workplace overall arrangement, infection prevention and the nucleic acid testing were analyzed, and the biological safety reliability and risk point were evaluated.Results:The indicators of imaging performance and radiation protection for 8 CT scanners in emergency hospitals could meet the requirements of national standards.Each of 2 makeshift hospitals had 3 CT rooms with the area of 38.8 m 2 and 4 mm Pb equivalent thickness of protective shielding. The CT rooms in module hospital and brick pattern hospital were 20.0 m 2, and 35.8 m 2 in areas, with 4 mm Pb equivalent and 3 mm Pb equivalent thickness of protection shielding, respectively. The 8 radiological diagnostic workplaces of the emergency hospitals were designed and constructed based on " three zones with two passage ways" . The result of the nucleic acid test indicated that the positive samples were found at the multiple sites such as scanning bed, internal of gantry and ground touched by patients in CT scanning room. The areas such as console panel and ground were risked of pollution by the virus infected hands and feet of radiographers. In addition, the similar positive samples were found in the areas in scanning room with no touch of patients, such as observation window and air outlet. Conclusions:8 CT scanners and rooms in 4 emergency hospitals basically meet the requirements of imaging performance and radiation protection. The disinfection of COVID-19 radiodiagnostic workplace should be standardized.

Objective To explore the spatial-temporal characteristics of influenza epidemic in Hubei from 2009 to 2020, and make short-term prediction to provide reference for influenza prevention and control strategies. Methods Time series seasonal decomposition model and geographic spatial analysis method were used to analyze spatial-temporal evolution characteristics of influenza prevalence in Hubei during 2009-2020. LSTM neural network model was used to predict the monthly influenza incidence from 2020 to 2023. Results Influenza was mainly prevalent in the end of winter and the beginning of spring (December to March) were periods of high influenza incidence. In recent years, the influenza pandemic has shown an increasing trend. Influenza epidemic was characterized by significant spatial differentiation, with ^“A-shaped point-axis structure^” surrounding counties were more severe . The epidemic center of gravity experienced a spatial evolution process from west to east and from north to south. LSTM neural network model predicted that although the influenza incidence rate from January 2020 to December 2023 is lower than that in 2019, it is still at a high level, and shows a peak epidemic in winter and spring. Conclusion Influenza epidemic in Hubei is characterized by a high epidemic period in late winter and early spring, and the southeast of Hubei is the key epidemic area. It is suggested that publicity and prevention and control should be strengthened according to people, time and place, and key populations and areas should be encouraged to receive influenza vaccines in advance.

Objective To find out the causes of food poisoning in a school banquet and identify the pathogenic bacteria, so as to provide evidence for the treatment of food poisoning. Methods A field epidemiological survey was conducted to search for cases, find suspicious poisoning meals and food, and collect cases and food samples for laboratory testing, to determine pathogenic pathogens and virulence genes. The pulsed field gel electrophoresis (PFGE) was applied to identify the homology of the pathogens. Results A total of 92 poisoning cases were found, and the incidence rate was 46.94%. The main clinical manifestations were diarrhea (93.48%), abdominal pain (86.96%), nausea (39.13%), vomiting (34.78%) and fever (17.39%). The median of onset latency was 17 hours. Vibrio parahaemolyticus was detected in samples from 3 patients (2 stools and 1 anal swab). The virulence gene trh was positive and the similarity coefficient of PFGE banding was 97.4%. Pathogenic bacteria were not detected in 10 food samples. The results of the case-control study showed that six types of food were suspicious (OR values were 15.75, 10.14, 8.44, 5.93, 5.56 and 4.71 respectively, P<0.05 and OR 95%CI>1), including couple lung slices and California bass with extremely high risk of exposure (OR values>10). Conclusion 　The food poisoning resulted from this enrollment banquet was caused by trh-positive Vibrio parahaemolyticus and no suspicious food was identified (the possibility of contamination by couples^' lung slices and California sea bass was high). It is suggested that the supervision and management of catering units and food safety publicity and education should be strengthened to reduce the occurrence of food-borne diseases from the source.

Objective To understand the status of new coronavirus contamination in the biosafety laboratory environment, identify key areas prone to contamination, and provide evidence for disinfection of central objects. Methods surfaces of high-frequency contact environment and protective equipment were sampled with moistened sterile cotton swabs after experiment and before disinfection, the results of the one-step real-time reverse transcription polymerase chain reaction (RT-PCR) of open reading frame 1ab and N fragment were used to evaluate the pollution status. Results Environmental surveys found 4 of 217 samples of environmental objects to be positive for new coronavirus RNA, that positive rate was 1.84%. Among them, BSL-3, BSL-2, and BSL-1 were sampled 23, 184, and 10 respectively. The 3 positive samples were from surfaces of nucleic acid extraction room of BSL-2 and from the handles of pass-through box, laboratory door handles and the outer surface of the alcohol watering pot respectively. The 1 positive sample was from the forearm of the protective clothing in BSL-2 laboratory. Conclusion There was a certain degree of virus pollution in key areas of the new coronavirus laboratory. The BSL-2 laboratory has a higher risk of environmental pollution than the BSL-3 and BSL-1 laboratories.