Porcine epidemic diarrhea virus (PEDV) is an intestinal coronavirus that can cause porcine epidemic diarrhea, leading to diarrhea, vomiting, weight loss, and even death in piglets. Due to the diversity of PEDV strains, traditional vaccines are difficult to sustainably and effectively prevent and control PEDV. This article reviews the strategies and mechanisms of active substances in regulating intracellular signaling pathways, viral proteins, and microbial metabolites to enhance the host immune function against PEDV. It emphasizes the prevention of PEDV resistance and the potential harm of PEDV breaking through interspecies barriers to the human society, aiming to provide reliable theoretical support for the development of new antiviral drugs or vaccines.
Porcine epidemic diarrhea virus/immunology* ; Animals ; Swine ; Swine Diseases/prevention & control* ; Antiviral Agents/pharmacology* ; Coronavirus Infections/virology* ; Viral Vaccines/immunology* ; Humans ; Signal Transduction

Porcine epidemic diarrhea (PED) is a major disease of pigs that inflicts heavy losses on the global pig industry. The etiologic agent is the porcine epidemic diarrhea virus (PEDV), which is assigned to the genus Alphacoronavirus in the family Coronaviridae. This review consists of five parts, the first of which provides a brief introduction to PEDV and its epidemiology. Part two outlines the passive immunity in new born piglets and the important role of colostrum, while the third part summarizes the characteristics of the immune systems of pregnant sows, discusses the concept of the "gut-mammary gland-secretory IgA(sIgA) axis" and the possible underpinning mechanisms, and proposes issues to be addressed when designing a PEDV live vaccine. The final two parts summarizes the advances in the R&D of PEDV vaccines and prospects future perspectives on prevention and control of PEDV, respectively.
Animals ; Antibodies, Viral ; Coronavirus Infections/veterinary* ; Female ; Immunization ; Porcine epidemic diarrhea virus ; Pregnancy ; Swine ; Swine Diseases/prevention & control* ; Viral Vaccines

Betacoronavirus ; COVID-19 ; China ; Coronavirus Infections/therapy* ; Humans ; Pandemics/prevention & control* ; Pneumonia, Viral/therapy* ; SARS-CoV-2

Betacoronavirus ; COVID-19 ; Coronavirus Infections/prevention & control* ; Humans ; Masks ; Pandemics/prevention & control* ; Pneumonia, Viral/prevention & control* ; SARS-CoV-2

OBJECTIVE: To establish reuse process of positive pressure powered air-filter protective hoods during coronavirus disease 2019 (COVID-19) epidemic. METHODS: The procedure of pretreatment, storage, recovery, cleaning, disinfection and sterilization process of positive pressure powered air-filter protective hoods, which were used in the treatment of COVID-19 infection patients was established in Central Sterile Supply Department of the hospital. The cleaning and disinfection effects of the protective hoods after treatment were examined by magnifying glass method, residual protein detection method, real-time PCR, and agar pour plate method. RESULTS: Twenty five used protective hoods underwent totally 135 times of washing, disinfecting and sterilizing procedures. After washing, all the protein residue tests and COVID-19 nucleic acid tests showed negative results. After sterilizing, all the protective hoods met sterility requirement. All the tested protective hoods were undamaged after reprocessing. CONCLUSIONS The established reuse procedures for used positive pressure powered air-filter protective hoods are safe.
Air Filters/virology* ; Betacoronavirus ; COVID-19 ; Coronavirus Infections/prevention & control* ; Disinfection/standards* ; Equipment Reuse/standards* ; Pandemics/prevention & control* ; Pneumonia, Viral/prevention & control* ; SARS-CoV-2 ; Sterilization/standards*

OBJECTIVE: To summarize the experience of perioperative prevention during double-lung transplantation for elderly patients with coronavirus disease 2019 (COVID-19). METHODS: Clinical data of 2 elderly patients with COVID-19 who underwent double-lung transplantation in the First Affiliated Hospital of Zhejiang University School of Medicine in March 2020 were retrospectively reviewed. Perioperative protective measures were introduced in terms of medical staffing, respiratory tract, pressure injuries, air in operating room, instruments and equipment, pathological specimens, and information management. RESULTS: Two cases of double-lung transplantation were successfully completed, and the patients had no operation-related complications. Extracorporeal membrane oxygenator was successfully removed 2 to 4 days after surgery and the patients recovered well. There was no infection among medical staff. CONCLUSIONS Adequate preoperative preparation, complete patient transfer procedures, proper placement of instruments and equipment, strengthening of intraoperative care management, and attention to prevention of pressure injury complications can maximize the safety of COVID-19 patients and medical staff.
Aged ; Betacoronavirus ; COVID-19 ; Coronavirus Infections ; Humans ; Lung Transplantation/standards* ; Pandemics ; Perioperative Care/standards* ; Pneumonia, Viral ; Postoperative Complications/prevention & control* ; Retrospective Studies ; SARS-CoV-2 ; Transplant Recipients

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new zoonotic agent that emerged in December 2019, causes coronavirus disease 2019 (COVID-19). This infection can be spread by asymptomatic, presymptomatic, and symptomatic carriers. SARS-CoV-2 spreads primarily via respiratory droplets during close person-to-person contact in a closed space, especially a building. This article summarizes the environmental factors involved in SARS-CoV-2 transmission, including a strategy to prevent SARS-CoV-2 transmission in a building environment. SARS-CoV-2 can persist on surfaces of fomites for at least 3 days depending on the conditions. If SARS-CoV-2 is aerosolized intentionally, it is stable for at least several hours. SARS-CoV-2 is inactivated rapidly on surfaces with sunlight. Close-contact aerosol transmission through smaller aerosolized particles is likely to be combined with respiratory droplets and contact transmission in a confined, crowded, and poorly ventilated indoor environment, as suggested by some cluster cases. Although evidence of the effect of aerosol transmission is limited and uncertainty remains, adequate preventive measures to control indoor environmental quality are required, based on a precautionary approach, because COVID-19 has caused serious global damages to public health, community, and the social economy. The expert panel for COVID-19 in Japan has focused on the "3 Cs," namely, "closed spaces with poor ventilation," "crowded spaces with many people," and "close contact." In addition, the Ministry of Health, Labour and Welfare of Japan has been recommending adequate ventilation in all closed spaces in accordance with the existing standards of the Law for Maintenance of Sanitation in Buildings as one of the initial political actions to prevent the spread of COVID-19. However, specific standards for indoor environmental quality control have not been recommended and many scientific uncertainties remain regarding the infection dynamics and mode of SARS-CoV-2 transmission in closed indoor spaces. Further research and evaluation are required regarding the effect and role of indoor environmental quality control, especially ventilation.
Aerosols ; Air Pollution, Indoor/prevention & control* ; Betacoronavirus/physiology* ; COVID-19 ; Coronavirus Infections/transmission* ; Crowding ; Environment, Controlled ; Humans ; Pandemics/prevention & control* ; Pneumonia, Viral/transmission* ; SARS-CoV-2 ; Ventilation

OBJECTIVE: To explore the infection prevention and control strategy of bedside blood purification treatment in corona virus disease 2019 (COVID-19) isolation ward, and to evaluate the effect of infection prevention and control management measures. METHODS: We summarized and analyzed the clinical features, infection status, outcome and infection prevention and control measures of bedside blood purification treatment patients in COVID-19 isolation ward from February 8, 2020 to March 31, 2020, analyzed the COVID-19 cross-infection between the patients and medical staffs, and the blood-borne pathogens cross-infection situation between the patients, and analyzed the effect of bundle prevention and control measures in controlling the occurrence and spread of cross-infection. RESULTS: A total of 101 COVID-19 patients were hospitalized in this COVID-19 isolation ward, of whom 10 patients (9.90%) received bedside blood purification treatment and the blood purification treatment method was continuous hemodialysis filtration (CVVHDF), and the 10 patients received 79 times of blood purification treatment in total. The prevention and control management measures adopted included divisional isolation, patient behavior isolation and patient placement, operator personal protection and hand hygiene, dialysis waste fluid disposal, isolation room air purification, object surfaces, medical devices and medical fabrics dis-infection management. There were no occurrence and spread of COVID-19 in the medical healthcare workers and blood-borne pathogens cross-infection in the patients. And all the twice throat swabs (two sampling interval > 1 day) of the medical staffs in COVID-19 virus nucleic acid test were negative. The 2 suspected COVID-19 patients' throat swab virus nucleic acid test and the COVID-19 IgG, IgM were always both negative, the chest CT showed no viral pneumonia. CONCLUSION Bedside blood purification treatment in the COVID-19 isolation ward, the occurrence and spread of healthcare associated infection can be effectively controlled through effective infection prevention and control management, including divisional isolation, patient behavior isolation and patient placement, operator personal protection and hand hygiene, dialysis waste fluid disposal, isolation room's air purification, object surfaces, medical devices and medical fabrics disinfection, which can provide experience for diagnosis, treatment and prevention and control of patients in the respiratory infectious disease ward.
Betacoronavirus ; COVID-19 ; Coronavirus Infections/therapy* ; Humans ; Infection Control/statistics & numerical data* ; Pandemics/prevention & control* ; Pneumonia, Viral/therapy* ; SARS-CoV-2

OBJECTIVE: To investigate the current situation of virus exposure risk incidents of nurses against corona virus disease 2019 (COVID-19) in Wuhan, and to provide reference evidence for nursing managers to protect nursing staff who were working in the isolation ward. METHODS: In the study, 308 nursing staff against COVID-19 working in the isolation ward in Wuhan were conveniently selected to participate in the investigation. The designed questionnaires including 7 kinds of protective exposure risk events were made by the team of researchers on the basis of literature review and interview with the nurses in Wuhan. All the participants recalled their working experience in the status of dressing in personal protective equipment and filled in the questionnaires online by WeChat according to the same instruction. RESULTS: The questionnaires were filled in validly by a total of 304 nursing staff, of whom 88.8% received emergency training on the prevention and dealing measurement of exposure risk events. The incidence of shoe cover contamination, falling off or torn was relatively high, about 53.6%. Due to the protection of gloves, the incidence of hand or skin contamination was relatively low, about 14.1%. The most nervousness of protective exposure risk event for nurses was N95 mask contamination, falling off or shifting, with a score of 8.2±2.3, showing a higher psychiatric burden. Single factor analysis found that the number of days in Wuhan was different, the number of the types of protective risk events occurred was different (χ²=14.562, P=0.024), orderly multivariate Logistic regression found that men were the independent protective factor for the number of the types of protective exposure risk events that occurred (P=0.019). CONCLUSION Protective exposure risk events may occur in the work of nursing staff working in the isolation ward in Wuhan. It is necessary to guide nurses to prevent the occurrence of protective exposure risk events and effectively deal with them, so as to prevent virus exposure and reduce psycholo-gical burden.
Betacoronavirus ; COVID-19 ; China ; Coronavirus Infections/transmission* ; Ear Protective Devices ; Humans ; Male ; Occupational Exposure/prevention & control* ; Pandemics/prevention & control* ; Pneumonia, Viral/transmission* ; Risk Factors ; SARS-CoV-2

OBJECTIVE: To determine the environmental contamination degree of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in corona virus disease 2019 (COVID-19) wards, to offer gui-dance for the infection control and to improve safety practices for medical staff, by sampling and detecting SARS-CoV-2 nucleic acid from the air of hospital wards, the high-frequency contact surfaces in the contaminated area and the surfaces of medical staff's protective equipment in a COVID-19 designated hospital in Wuhan, China. METHODS: From March 11 to March 19, 2020, we collected air samples from the clean area, the buffer room and the contaminated area respectively in the COVID-19 wards using a portable bioaerosol concentrator WA-15. And sterile premoistened swabs were used to sample the high-frequency contacted surfaces in the contaminated area and the surfaces of medical staff's protective equipment including outermost gloves, tracheotomy operator's positive pressure respiratory protective hood and isolation clothing. The SARS-CoV-2 nucleic acid of the samples were detected by real-time fluorescence quantitative PCR. During the isolation medical observation period, those medical staff who worked in the COVID-19 wards were detected for SARS-CoV-2 nucleic acid with oropharyngeal swabs, IgM and IgG antibody in the sera, and chest CT scans to confirm the infection status of COVID-19. RESULTS: No SARS-CoV-2 nucleic acid was detected in the tested samples, including the 90 air samples from the COVID-19 wards including clean area, buffer room and contaminated area, the 38 high-frequency contact surfaces samples of the contaminated area and 16 surface samples of medical staff's protective equipment including outermost gloves and isolation clothing. Moreover, detection of SARS-CoV-2 nucleic acid by oropharyngeal swabs and IgM, IgG antibodies in the sera of all the health-care workers who participated in the treatment for COVID-19 were all negative. Besides, no chest CT scan images of medical staff exhibited COVID-19 lung presentations. CONCLUSION Good ventilation conditions, strict disinfection of environmental facilities in hospital wards, guidance for correct habits in patients, and strict hand hygiene during medical staff are important to reduce the formation of viral aerosols, cut down the aerosol load, and avoid cross-infection in isolation wards. In the face of infectious diseases that were not fully mastered but ma-naged as class A, it is safe for medical personnel to be equipped at a high level.
Betacoronavirus ; COVID-19 ; China ; Coronavirus Infections ; Humans ; Medical Staff ; Pandemics ; Pneumonia, Viral ; Protective Devices ; SARS-CoV-2 ; Severe Acute Respiratory Syndrome/prevention & control*