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

Coronavirus disease 2019 (COVID-19) is a grade B infectious disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In pace with the spreading of the disease, biosafety risk of the biological specimen preservation in biobanks has been significantly increased and biosafety protection during biological specimen preservation become increasingly important. According to the related national rules and the corresponding guidelines of Chinese Medical Association, this paper introduced the etiology about SARS-CoV-2, epidemiology about COVID-19, and the biosafety protection principles of individuals and biological specimen storage places in the process of personal protection, protection of collection, transport, handling, preservation, detection, post-detection disposal and emergencies of biological specimen. Emphasized to carry out a strict biosafety-risk assessment on biological specimen basing on virus load information, infectivity, and sample type (possible contact transmission, aerosol transmission, and fecal oral transmission).
Betacoronavirus ; isolation & purification ; Containment of Biohazards ; standards ; Coronavirus Infections ; epidemiology ; prevention & control ; transmission ; Humans ; Pandemics ; prevention & control ; Pneumonia, Viral ; epidemiology ; prevention & control ; transmission ; Prevalence ; Risk Assessment ; Specimen Handling ; standards

The three known human highly pathogenic coronaviruses are severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Human highly pathogenic coronaviruses are composed of non-structural proteins, structural proteins and accessory proteins. Viral particles recognize host receptors via spike glycoprotein (S protein), enter host cells by membrane fusion, replicate in host cells through large replication-transcription complexes, and promote proliferation by interfering with and suppressing the host's immune response. Human highly pathogenic coronaviruses are hosted by humans and vertebrates. Viral particles are transmitted through droplets, contact and aerosols or likely through digestive tract, urine, eyes and other routes. This review discusses the mechanisms of proliferation and transmission of highly pathogenic human coronaviruses based on the results of existing research, providing basis for future study on interrupting the transmission and pathogenicity of human highly pathogenic coronaviruses.
Animals ; Betacoronavirus ; physiology ; Coronavirus Infections ; immunology ; transmission ; virology ; Humans ; Middle East Respiratory Syndrome Coronavirus ; physiology ; Pandemics ; Pneumonia, Viral ; immunology ; transmission ; virology ; SARS Virus ; physiology ; Virus Replication ; physiology

A novel coronavirus that emerged in late 2019 rapidly spread around the world. Most severe cases need endotracheal intubation and mechanical ventilation, and some mild cases may need emergent surgery under general anesthesia. The novel coronavirus was reported to transmit via droplets, contact and natural aerosols from human to human. Therefore, aerosol-producing procedures such as endotracheal intubation and airway suction may put the healthcare providers at high risk of nosocomial infection. Based on recently published articles, this review provides detailed feasible recommendations for primary anesthesiologists on infection prevention in operating room during COVID-19 outbreak.
Anesthesiologists ; standards ; Betacoronavirus ; Coronavirus Infections ; epidemiology ; prevention & control ; transmission ; Cross Infection ; epidemiology ; prevention & control ; transmission ; Disease Outbreaks ; prevention & control ; Humans ; Intubation, Intratracheal ; methods ; standards ; Operating Rooms ; methods ; standards ; Pandemics ; prevention & control ; Pneumonia, Viral ; epidemiology ; prevention & control ; transmission

This article evaluates the potential influence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in pregnant women on the development of coronavirus disease 2019 in neonates and discusses the possibility of mother-to-child vertical transmission of SARS-CoV-2. With reference to related articles published up to now and the information on official websites, a retrospective review was performed for the clinical manifestations and laboratory examination results of the neonates born to the mothers with infection during pregnancy during the epidemics of severe acute respiratory syndrome and Middle East respiratory syndrome and after the outbreak of SARS-CoV-2 infection since December 2019. Based on the limited data, there is no conclusive evidence for mother-to-child vertical transmission of coronavirus disease 2019, and more cases need to be collected for further evaluation.
Betacoronavirus ; Child ; Coronavirus Infections ; Female ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Pandemics ; Pneumonia, Viral ; Pregnancy ; Pregnancy Complications, Infectious ; Pregnancy Outcome ; Retrospective Studies ; Severe Acute Respiratory Syndrome

2019-nCoV epidemic was firstly reported at late December of 2019 and has caused a global outbreak of COVID-19 now. Saliva, a biofluid largely generated from salivary glands in oral cavity, has been reported 2019-nCoV nucleic acid positive. Besides lungs, salivary glands and tongue are possibly another hosts of 2019-nCoV due to expression of ACE2. Close contact or short-range transmission of infectious saliva droplets is a primary mode for 2019-nCoV to disseminate as claimed by WHO, while long-distance saliva aerosol transmission is highly environment dependent within indoor space with aerosol-generating procedures such as dental practice. So far, no direct evidence has been found that 2019-nCoV is vital in air flow for long time. Therefore, to prevent formation of infectious saliva droplets, to thoroughly disinfect indoor air and to block acquisition of saliva droplets could slow down 2019-nCoV dissemination. This review summarizes diagnostic value of saliva for 2019-nCoV, possibly direct invasion into oral tissues, and close contact transmission of 2019-nCoV by saliva droplets, expecting to contribute to 2019-nCoV epidemic control.
Betacoronavirus ; isolation & purification ; pathogenicity ; Clinical Laboratory Techniques ; Coronavirus Infections ; diagnosis ; transmission ; Humans ; Mouth ; virology ; Pandemics ; Peptidyl-Dipeptidase A ; metabolism ; Pharynx ; virology ; Pneumonia, Viral ; diagnosis ; transmission ; SARS Virus ; isolation & purification ; pathogenicity ; Saliva ; virology

Betacoronavirus ; Coronavirus ; Coronavirus Infections ; epidemiology ; prevention & control ; Disease Transmission, Infectious ; prevention & control ; Guidelines as Topic ; Humans ; Infection Control ; organization & administration ; Pandemics ; prevention & control ; Personal Protective Equipment ; standards ; Pneumonia, Viral ; epidemiology ; prevention & control ; Primary Prevention ; methods ; standards ; Safety ; standards ; Safety Management

As of Apr. 22, 2020, the World Health Organization (2020) has reported over 2.4 million confirmed coronavirus disease 2019 (COVID-19) patients and 169 151 deaths. Recent articles have uncovered genomic characteristics and clinical features of COVID-19 (Chan et al., 2020; Chang et al., 2020; Guan et al., 2020; Zhu et al., 2020), while our understanding of COVID-19 is still limited. As suggested by guidelines promoted by the General Office of National Health Commission of the People's Republic of China (2020) (from Versions 1 to 6), discharged standards for COVID-19 were still dependent on viral real-time polymerase chain reaction (RT-PCR) tests of respiratory specimens, showing that recovered COVID-19 patients with twice negative RT-PCR could meet discharge criteria. Here, we examined two cases in which nucleic acid test results were inconsistent with clinical and radiological findings, leading to suboptimal care.
Adult ; Betacoronavirus ; China ; Clinical Laboratory Techniques ; Coronavirus Infections ; diagnosis ; transmission ; Female ; Humans ; Male ; Middle Aged ; Pandemics ; Patient Discharge ; Pneumonia, Viral ; diagnosis ; transmission ; Real-Time Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; Sputum ; virology

The recently emerged novel coronavirus pneumonia, named the coronavirus disease 2019 (COVID-19), shares several clinical characteristics with severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), and spread rapidly throughout China in December of 2019 (Huang et al., 2020). The pathogen 2019 novel coronavirus (2019-nCoV) is now named SARS coronavirus 2 (SARS-CoV-2) and is highly infectious. As of Apr. 9, 2020, over 80 000 confirmed cases had been reported, with an estimated mortality rate of 4.0% (Chinese Center for Disease Control and Prevention, 2020). Person-to-person transmission and familial clustering have been reported (Chan et al., 2020; Nishiura et al., 2020; Phan et al., 2020). However, there is no evidence of fetal intrauterine infection in pregnant women who have been infected with SARS-CoV-2 in their third trimester (Chen et al., 2020). It is unclear whether breastfeeding transmits the virus from previously infected and recovered mothers to their babies. Here we report the clinical course of a pregnant woman with COVID-19. In order to determine whether SARS-CoV-2 can be transmitted to newborns through breastfeeding, we measured viral RNA in the patient's breastmilk samples at different time points after delivery.
Adult ; Betacoronavirus ; Breast Feeding ; China ; Coronavirus Infections ; diagnosis ; Female ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Milk, Human ; virology ; Pandemics ; Pneumonia, Viral ; diagnosis ; Pregnancy ; Pregnancy Complications, Infectious ; virology ; RNA, Viral ; isolation & purification

Since its emergence in December 2019, corona virus disease 2019 (COVID-19) has impacted several countries, affecting more than 90 thousand patients and making it a global public threat. The routes of transmission are direct contact, and droplet and possible aerosol transmissions. Due to the unique nature of dentistry, most dental procedures generate significant amounts of droplets and aerosols, posing potential risks of infection transmission. Understanding the significance of aerosol transmission and its implications in dentistry can facilitate the identification and correction of negligence in daily dental practice. In addition to the standard precautions, some special precautions that should be implemented during an outbreak have been raised in this review.
Aerosols ; Betacoronavirus ; Coronavirus Infections ; prevention & control ; transmission ; Cross Infection ; prevention & control ; Dentistry ; Hand Hygiene ; Humans ; Infection Control ; methods ; Pandemics ; prevention & control ; Personal Protective Equipment ; Pneumonia, Viral ; prevention & control ; transmission