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Stability of SARS Coronavirus in Human Specimens and Environment and Its Sensitivity to Heating and UV Irradiation
Abstract
The causal agent for SARS is considered as a novel coronavirus that has never been described both in human and animals previously. The stability of SARS coronavirus in human specimens and in environments was studied.
Using a SARS coronavirus strain CoV-P9, which was isolated from pharyngeal swab of a probable SARS case in Beijing, its stability in mimic human specimens and in mimic environment including surfaces of commonly used materials or in household conditions, as well as its resistance to temperature and UV irradiation were analyzed. A total of 10(6) TCID50 viruses were placed in each tested condition, and changes of the viral infectivity in samples after treatments were measured by evaluating cytopathic effect (CPE) in cell line Vero-E6 at 48 h after infection.
The results showed that SARS coronavirus in the testing condition could survive in serum, 1:20 diluted sputum and feces for at least 96 h, whereas it could remain alive in urine for at least 72 h with a low level of infectivity. The survival abilities on the surfaces of eight different materials and in water were quite comparable, revealing reduction of infectivity after 72 to 96 h exposure. Viruses stayed stable at 4 degrees C, at room temperature (20 degrees C) and at 37 degrees C for at least 2 h without remarkable change in the infectious ability in cells, but were converted to be non-infectious after 90-, 60- and 30-min exposure at 56 degrees C, at 67 degrees C and at 75 degrees C, respectively. Irradiation of UV for 60 min on the virus in culture medium resulted in the destruction of viral infectivity at an undetectable level.
The survival ability of SARS coronavirus in human specimens and in environments seems to be relatively strong. Heating and UV irradiation can efficiently eliminate the viral infectivity.
... Secretory autophagy is known to promote viral maturation, egress, and cell-cell spreading and is initiated by SFTSV infection. In addition, the SFTSV infection did not exhibit a cytopathic effect, similar to some other viruses such as the SARS coronavirus [34]. Instead of merely observing a static state, the study revealed a dynamic morphological transformation (Supplementary Figure S1) over two days, marked by the emergence of multinucleated cells and a sharp increase in the concentration of the virus by the third day after infection. ...
Abstract
In our prior investigations, we elucidated the role of the tryptophan-to-tyrosine substitution at the 61st position in the nonstructural protein NSsW61Y in diminishing the interaction between nonstructural proteins (NSs) and nucleoprotein (NP), impeding viral replication. In this study, we focused on the involvement of NSs in replication via the modulation of autophagosomes. Initially, we examined the impact of NP expression levels, a marker for replication, upon the infection of HeLa cells with severe fever thrombocytopenia syndrome virus (SFTSV), with or without the inhibition of NP binding. Western blot analysis revealed a reduction in NP levels in NSsW61Y-expressing conditions. Furthermore, the expression levels of the canonical autophagosome markers p62 and LC3 decreased in HeLa cells expressing NSsW61Y, revealing the involvement of individual viral proteins on autophagy. Subsequent experiments confirmed that NSsW61Y perturbs autophagy flux, as evidenced by reduced levels of LC3B and p62 upon treatment with chloroquine, an inhibitor of autophagosome–lysosome fusion. LysoTracker staining demonstrated a decrease in lysosomes in cells expressing the NS mutant compared to those expressing wild-type NS. We further explored the mTOR-associated regulatory pathway, a key regulator affected by NS mutant expression. The observed inhibition of replication could be linked to conformational changes in the NSs, impairing their binding to NP and altering mTOR regulation, a crucial upstream signaling component in autophagy. These findings illuminate the intricate interplay between NSsW61Y and the suppression of host autophagy machinery, which is crucial for the generation of autophagosomes to facilitate viral replication.
Keywords: SFTSV; NSs; NP; replication; autophagosome
... Chin et al. reported that after 2 days, no infective SARS-CoV-2 was detected on the treated wood surface in their experiments (room temperature, RH 65%) while Duan et al. reported that SARS-CoV stayed infectious for 4−5 days at room temperature on wood board. 16,23 In our studies, we simulated standardized test conditions by incubating the virus on the surface at room temperature and over 90% RH. Additionally, it was important to note that indoor humidity levels can vary significantly, especially in Nordic countries. ...
The ongoing challenge of viral transmission, exemplified by the Covid pandemic and recurrent viral outbreaks, necessitates the exploration of sustainable antiviral solutions. This study investigates the underexplored antiviral potential of wooden surfaces. We evaluated the antiviral efficacy of various wood types, including coniferous and deciduous trees, against enveloped coronaviruses and nonenveloped enteroviruses like coxsackie virus A9. Our findings revealed excellent antiviral activity manifesting already within 10 to 15 min in Scots pine and Norway spruce, particularly against enveloped viruses. In contrast, other hardwoods displayed varied efficacy, with oak showing effectiveness against the enterovirus. This antiviral activity was consistently observed across a spectrum of humidity levels (20 to 90 RH%), while the antiviral efficacy manifested itself more rapidly at 37 °C vs 21 °C. Key to our findings is the chemical composition of these woods. Resin acids and terpenes were prevalent in pine and spruce, correlating with their antiviral performance, while oak’s high phenolic content mirrored its efficacy against enterovirus. The pine surface absorbed a higher fraction of the coronavirus in contrast to oak, whereas enteroviruses were not absorbed on those surfaces. Thermal treatment of wood or mixing wood with plastic, such as in wood-plastic composites, strongly compromised the antiviral functionality of wood materials. This study highlights the role of bioactive chemicals in the antiviral action of wood and opens new avenues for employing wood surfaces as a natural and sustainable barrier against viral transmissions.
... Furthermore, freezing temperatures can aggravate diarrhea, easily causing winter dysentery. However, other studies have shown that BCoV-induced diarrhea was not correlated with low temperatures [30,33,46]. HE and S are critical for BCoV invasion and cellular release and are critical antibodyneutralization epitopes. ...
Bovine coronavirus (BCoV), bovine rotavirus, bovine viral diarrhea virus, and bovine astrovirus are the most common intestinal pathogenic viruses causing diarrhea in cattle. We collected 1646 bovine fecal samples from January 2020 to August 2023. BCoV was the major pathogen detected, with a positive rate of 34.02% (560/1646). Of the 670 diarrheal samples and 976 asymptomatic samples, 209 and 351 were BCoV-positive, respectively. Studying the relevance of diarrhea associated with BCoV has shown that the onset of diarrheal symptoms post-infection is strongly correlated with the cattle’s age and may also be related to the breed. We amplified and sequenced the hemagglutinin esterase (HE), spike protein, and whole genomes of the partially positive samples and obtained six complete HE sequences, seven complete spike sequences, and six whole genomes. Molecular characterization revealed that six strains were branched Chinese strains, Japanese strains, and partial American strains from the GⅡb subgroup. Strains HBSJZ2202 and JSYZ2209 had four amino acid insertions on HE. We also analyzed ORF1a and found disparities across various regions within GIIb, which were positioned on separate branches within the phylogenetic tree. This work provides data for further investigating the epidemiology of BCoV and for understanding and analyzing BCoV distribution and dynamics.
... According to Duan et al. (2003), healthcare providers who care for infected patients must wear safeguarding equipment such as FFP3 masks or N95, eye protection, gloves and gowns to restrict the spread of the disease. At present, laboratory research is underway to create a vaccine for coronavirus. ...
Coronaviruses (CoV) are a large family of viruses that cause serious illness in humans and other animals. In humans, they can trigger a variety of respiratory illnesses, including the common cold, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). The virus is now known as the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The disease it causes is called coronavirus disease 2019 (Covid-19). Like other coronaviruses, it has also come from animals. The majority of virus-infected individuals will experience a mild to severe respiratory disease and will recover without the need for special care. Nonetheless, some people will get serious illnesses and need to see a doctor. Serious sickness is more likely to strike older persons and those with underlying medical illnesses including cancer, diabetes, cardiovascular disease, or chronic respiratory diseases. Covid-19 can cause anyone to become very ill or pass away at any age. During epidemics, up to one-third of the adult community-acquired upper respiratory tract infections. Furthermore, some coronaviruses may cause diarrhea in young children and infants. Mild to moderate respiratory illness is typical for those infected with the Covid-19 virus, but most people will recover without any special treatment. People over the age of 65 and those who already have conditions like high blood pressure, diabetes, asthma, or cancer are at a higher risk of becoming seriously ill.
... This method is limited to some viruses such as influenza viruses that induce cell lysis or death and form plaques on the cell monolayer in the cell culture plate; however, many viruses do not form plaques and only induce recognizable CPE [109] . The end-point dilution method was used to quantify the effects of the 10-fold diluted viruses added to the cell monolayer, and the viral dilution in 50% of cells with CPE (tissue culture infective dose 50%, TCID 50 ) was determined after a few days [110] . However, viral detection using culturing methods still has great challenges because of the low recovery of infectious viruses in real environment. ...
The environmental stability of infectious viruses in the laboratory setting is crucial to the transmission potential of human respiratory viruses. Different experimental techniques or conditions used in studies over the past decades have led to diverse understandings and predictions for the stability of viral infectivity in the atmospheric environment. In this paper, we review the current knowledge on the effect of simulated atmospheric conditions on the infectivity of respiratory viruses, mainly focusing on influenza viruses and coronaviruses, including severe acute respiratory syndrome coronavirus 2 and Middle East respiratory syndrome coronavirus. First, we summarize the impact of the experimental conditions on viral stability; these involve the methods of viral aerosol generation, storage during aging and collection, the virus types and strains, the suspension matrixes, the initial inoculum volumes and concentrations, and the drying process. Second, we summarize and discuss the detection methods of viral infectivity and their disadvantages. Finally, we integrate the results from the reviewed studies to obtain an overall understanding of the effects of atmospheric environmental conditions on the decay of infectious viruses, especially aerosolized viruses. Overall, this review highlights the knowledge gaps in predicting the ability of viruses to maintain infectivity during airborne transmission.
... MERS-CoV can survive on inanimate surfaces for a long period of time. The factors may be the types of surfaces, the titer of the virus, variations of MERS strains, deposition mode, humidity, temperature, and determination methods (Duan et al., 2003;van Doremalen et al., 2013). Many reports have illustrated that MERS-CoV can be present on dry surfaces for a period of time to induce infection. ...
The Middle East Respiratory Syndrome (MERS) was first recorded in 2012 in Saudi Arabia, where infected people suffered from rapidly progressive acute respiratory distress after direct contact with infected dromedary camels, which act as reservoirs for this disease. Human cases reached 2617 infected and 947 deaths at the end of 2023. In this review article, different points have been discussed, such as epidemiology and recent diagnostic techniques, the current situation of MERS, especially in Egypt, and risk factors in addition to control and prevention. There have been 54 publications about MERS and Egypt in PubMed platform from 2013 until 2023. The highest numbers (10) were recorded in 2019, 2020, and 2021. To decrease the prevalence of MERS in humans, it is important to reduce the prevalence of the virus in camels. The aim of this article is to shed some light on the negative hazards of this serious disease, not only in humans but also the role of camels in this regard.
In healthcare settings, contaminated surfaces play an important role in the transmission of nosocomial pathogens potentially resulting in healthcare-associated infections (HAI). Pathogens can be transmitted directly from frequent hand-touch surfaces close to patients or indirectly by staff and visitors. HAI risk depends on exposure, extent of contamination, infectious dose (ID), virulence, hygiene practices, and patient vulnerability. This review attempts to close a gap in previous reviews on persistence/tenacity by only including articles ( n = 171) providing quantitative data on re-cultivable pathogens from fomites for a better translation into clinical settings. We have therefore introduced the new term “replication capacity” (RC). The RC is affected by the degree of contamination, surface material, temperature, relative humidity, protein load, organic soil, UV-light (sunlight) exposure, and pH value. In general, investigations into surface RC are mainly performed in vitro using reference strains with high inocula. In vitro data from studies on 14 Gram-positive, 26 Gram-negative bacteria, 18 fungi, 4 protozoa, and 37 viruses. It should be regarded as a worst-case scenario indicating the upper bounds of risks when using such data for clinical decision-making. Information on RC after surface contamination could be seen as an opportunity to choose the most appropriate infection prevention and control (IPC) strategies. To help with decision-making, pathogens characterized by an increased nosocomial risk for transmission from inanimate surfaces (“fomite-borne”) are presented and discussed in this systematic review. Thus, the review offers a theoretical basis to support local risk assessments and IPC recommendations.
The current pandemic generates plastic waste from the medical field, mainly consisting of polystyrene, polypropylene, polyethylene terephthalate, nylon, and polyethylene. COVID-19 outbreak has become a universal health hazard, leading to severe human respiratory tract infections via droplets, infected palms, or surfaces. Personal protection equipment (PPE) must be worn at all times to avoid contracting COVID, which creates a huge problem for the PPE supply chain made of single-use plastic. The greatest challenge is to minimize the decontaminated PPE waste generated with the help of the reuse and recycling of PPEs so that the abandoned PPE waste can be minimized. Because new research has recently improved the reliability of reprocessing technologies, reusing PPE could be a viable short-term solution to the COVID-19 epidemic. These include vaporized hydrogen peroxide disinfecting techniques, ultraviolet light disinfecting techniques, thermal disinfecting techniques like pyrolysis, a microwave technique, and many more. The study's main objective is to generate a list of all the relevant literature on various PPE sterilizing processes in order to assist readers in determining their best options.
This review provides an overview of the inactivation of pathogenic microorganisms using deep-UV light. Specifically, it discusses bacteria and viruses, presenting inactivation mechanisms and outlining key considerations for evaluating the effectiveness of inactivation. In addition, it also presents the actual inactivation effect of viruses using deep-UV LEDs, which have garnered significant attention in recent years.
In March 2003, a novel coronavirus (SARS-CoV) was discovered in association with cases of severe acute respiratory syndrome (SARS). The sequence of the complete genome of SARS-CoV was determined, and the initial characterization of the viral genome is presented in this report. The genome of SARS-CoV is 29,727 nucleotides in length and has 11 open reading frames, and its genome organization is similar to that of other coronaviruses. Phylogenetic analyses and sequence comparisons showed that SARS-CoV is not closely related to any of the previously characterized coronaviruses.
Information on the clinical features of the severe acute respiratory syndrome (SARS) will be of value to physicians caring for patients suspected of having this disorder.
We abstracted data on the clinical presentation and course of disease in 10 epidemiologically linked Chinese patients (5 men and 5 women 38 to 72 years old) in whom SARS was diagnosed between February 22, 2003, and March 22, 2003, at our hospitals in Hong Kong, China.
Exposure between the source patient and subsequent patients ranged from minimal to that between patient and health care provider. The incubation period ranged from 2 to 11 days. All patients presented with fever (temperature, >38 degrees C for over 24 hours), and most presented with rigor, dry cough, dyspnea, malaise, headache, and hypoxemia. Physical examination of the chest revealed crackles and percussion dullness. Lymphopenia was observed in nine patients, and most patients had mildly elevated aminotransferase levels but normal serum creatinine levels. Serial chest radiographs showed progressive air-space disease. Two patients died of progressive respiratory failure; histologic analysis of their lungs showed diffuse alveolar damage. There was no evidence of infection by Mycoplasma pneumoniae, Chlamydia pneumoniae, or Legionella pneumophila. All patients received corticosteroid and ribavirin therapy a mean (+/-SD) of 9.6+/-5.42 days after the onset of symptoms, and eight were treated earlier with a combination of beta-lactams and macrolide for 4+/-1.9 days, with no clinical or radiologic efficacy.
SARS appears to be infectious in origin. Fever followed by rapidly progressive respiratory compromise is the key complex of signs and symptoms from which the syndrome derives its name. The microbiologic origins of SARS remain unclear.
There has been an outbreak of the severe acute respiratory syndrome (SARS) worldwide. We report the clinical, laboratory, and radiologic features of 138 cases of suspected SARS during a hospital outbreak in Hong Kong.
From March 11 to 25, 2003, all patients with suspected SARS after exposure to an index patient or ward were admitted to the isolation wards of the Prince of Wales Hospital. Their demographic, clinical, laboratory, and radiologic characteristics were analyzed. Clinical end points included the need for intensive care and death. Univariate and multivariate analyses were performed.
There were 66 male patients and 72 female patients in this cohort, 69 of whom were health care workers. The most common symptoms included fever (in 100 percent of the patients); chills, rigors, or both (73.2 percent); and myalgia (60.9 percent). Cough and headache were also reported in more than 50 percent of the patients. Other common findings were lymphopenia (in 69.6 percent), thrombocytopenia (44.8 percent), and elevated lactate dehydrogenase and creatine kinase levels (71.0 percent and 32.1 percent, respectively). Peripheral air-space consolidation was commonly observed on thoracic computed tomographic scanning. A total of 32 patients (23.2 percent) were admitted to the intensive care unit; 5 patients died, all of whom had coexisting conditions. In a multivariate analysis, the independent predictors of an adverse outcome were advanced age (odds ratio per decade of life, 1.80; 95 percent confidence interval, 1.16 to 2.81; P=0.009), a high peak lactate dehydrogenase level (odds ratio per 100 U per liter, 2.09; 95 percent confidence interval, 1.28 to 3.42; P=0.003), and an absolute neutrophil count that exceeded the upper limit of the normal range on presentation (odds ratio, 1.60; 95 percent confidence interval, 1.03 to 2.50; P=0.04).
SARS is a serious respiratory illness that led to significant morbidity and mortality in our cohort.
A worldwide outbreak of severe acute respiratory syndrome (SARS) has been associated with exposures originating from a single ill health care worker from Guangdong Province, China. We conducted studies to identify the etiologic agent of this outbreak.
We received clinical specimens from patients in seven countries and tested them, using virus-isolation techniques, electron-microscopical and histologic studies, and molecular and serologic assays, in an attempt to identify a wide range of potential pathogens.
None of the previously described respiratory pathogens were consistently identified. However, a novel coronavirus was isolated from patients who met the case definition of SARS. Cytopathological features were noted in Vero E6 cells inoculated with a throat-swab specimen. Electron-microscopical examination revealed ultrastructural features characteristic of coronaviruses. Immunohistochemical and immunofluorescence staining revealed reactivity with group I coronavirus polyclonal antibodies. Consensus coronavirus primers designed to amplify a fragment of the polymerase gene by reverse transcription-polymerase chain reaction (RT-PCR) were used to obtain a sequence that clearly identified the isolate as a unique coronavirus only distantly related to previously sequenced coronaviruses. With specific diagnostic RT-PCR primers we identified several identical nucleotide sequences in 12 patients from several locations, a finding consistent with a point-source outbreak. Indirect fluorescence antibody tests and enzyme-linked immunosorbent assays made with the new isolate have been used to demonstrate a virus-specific serologic response. This virus may never before have circulated in the U.S. population.
A novel coronavirus is associated with this outbreak, and the evidence indicates that this virus has an etiologic role in SARS. Because of the death of Dr. Carlo Urbani, we propose that our first isolate be named the Urbani strain of SARS-associated coronavirus.
We sequenced the 29,751-base genome of the severe acute respiratory syndrome (SARS)-associated coronavirus known as the Tor2 isolate. The genome sequence reveals that this coronavirus is only moderately related to other known coronaviruses, including two human coronaviruses, HCoV-OC43 and HCoV-229E. Phylogenetic analysis of the predicted viral proteins indicates that the virus does not closely resemble any of the three previously known groups of coronaviruses. The genome sequence will aid in the diagnosis of SARS virus infection in humans and potential animal hosts (using polymerase chain reaction and immunological tests), in the development of antivirals (including neutralizing antibodies), and in the identification of putative epitopes for vaccine development.
The susceptibility of laboratory mice to intranasal and contact infection with mouse hepatitis virus (MHV)-related coronaviruses was tested in infant CD1 mice. One day old mouse pups were inoculated intranasally with respiratory MHV-S, enteric MHV-Y, rat sialodacryoadenitis virus (SDAV), human coronavirus OC43 (HCV-OC43) or bovine coronavirus (BCV). Twenty-four hours later, they were placed in direct contact with age matched sham inoculated pups. Indices of infection in virus inoculated mice included lesions by histopathology and viral antigen by immunoperoxidase histochemistry in brain, lung, liver and intestine at 3 days after inoculation. Indices of infection in contact mice included mortality or seroconversion by 21 days after exposure. Infant mice were susceptible to infection with all five viruses. Transmission by direct contact exposure occurred with MHV and SDAV, but not HCV or BCV. Furthermore, adult mice were not susceptible to infection with HCV. Tissue distribution of lesions and antigen varied markedly among viruses, indicating that they do not induce the same disease as MHV. This study demonstrates that although these coronaviruses are antigenically closely related, they are biologically different viruses and disease patterns in susceptible infant mice can be used to differentiate viruses.
Rhinoviruses are picornaviruses that cause colds. They are naturally temperature sensitive and highly adapted to grow in respiratory epithelium. Coronaviruses are structurally quite different, being enveloped viruses but are also adapted to grow in respiratory epithelium and also cause colds.
The quasispecies nature of three animal pathogenic RNA viruses of field origin was examined by testing variants of classical swine fever virus (CSFV) originating from geographically different areas, feline coronavirus (FCoV) detected from the same animal by successive sampling, and rabbit haemorrhagic disease virus (RHDV) originating from successive outbreaks in the same geographic area. Clinical samples were investigated using reverse transcriptase polymerase chain reaction (RT-PCR) and ensuing single strand conformational polymorphism (SSCP) assay. By the combination of these methods even subtle differences could be detected among the amplified fragments of the same virus species of different origin. FCoV proved to comprise the most and CSFV the less heterogeneous virus quasispecies. The results show that the combination of RT-PCR and SSCP provides novel and highly sensitive means for the characterisation of RNA viruses, with special regard to genome composition, evolution, features of pathogenicity and molecular epizootiology.
An outbreak of severe acute respiratory syndrome (SARS) has been reported in Hong Kong. We investigated the viral cause and clinical presentation among 50 patients.
We analysed case notes and microbiological findings for 50 patients with SARS, representing more than five separate epidemiologically linked transmission clusters. We defined the clinical presentation and risk factors associated with severe disease and investigated the causal agents by chest radiography and laboratory testing of nasopharyngeal aspirates and sera samples. We compared the laboratory findings with those submitted for microbiological investigation of other diseases from patients whose identity was masked.
Patients' age ranged from 23 to 74 years. Fever, chills, myalgia, and cough were the most frequent complaints. When compared with chest radiographic changes, respiratory symptoms and auscultatory findings were disproportionally mild. Patients who were household contacts of other infected people and had older age, lymphopenia, and liver dysfunction were associated with severe disease. A virus belonging to the family Coronaviridae was isolated from two patients. By use of serological and reverse-transcriptase PCR specific for this virus, 45 of 50 patients with SARS, but no controls, had evidence of infection with this virus.
A coronavirus was isolated from patients with SARS that might be the primary agent associated with this disease. Serological and molecular tests specific for the virus permitted a definitive laboratory diagnosis to be made and allowed further investigation to define whether other cofactors play a part in disease progression.