Subject(s)
Conscious Sedation , Respiration, Artificial , Bodily Secretions , Humans , Hypnotics and SedativesABSTRACT
SARS-CoV-2 and other microbes within aerosol particles can be partially shielded from UV radiation. The particles refract and absorb light, and thereby reduce the UV intensity at various locations within the particle. Previously, we demonstrated shielding in calculations of UV intensities within spherical approximations of SARS-CoV-2 virions within spherical particles approximating dried-to-equilibrium respiratory fluids. The purpose of this paper is to extend that work to survival fractions of virions (i.e., fractions of virions that can infect cells) within spherical particles approximating dried respiratory fluids, and to investigate the implications of these calculations for using UV light for disinfection. The particles may be on a surface or in air. Here, the survival fraction (S) of a set of individual virions illuminated with a UV fluence (F, in J/m2) is assumed described by S(kF) = exp(-kF), where k is the UV inactivation rate constant (m2/J). The average survival fraction (Sp) of the simulated virions in a group of particles is calculated using the energy absorbed by each virion in the particles. The results show that virions within particles of dried respiratory fluids can have larger Sp than do individual virions. For individual virions, and virions within 1-, 5-, and 9-µm particles illuminated (normal incidence) on a surface with 260-nm UV light, the Sp = 0.00005, 0.0155, 0.22, and 0.28, respectively, when kF = 10. The Sp decrease to <10-7, <10-7, 0.077, and 0.15, respectively, for kF = 100. Results also show that illuminating particles with UV beams from widely separated directions can strongly reduce the Sp. These results suggest that the size distributions and optical properties of the dried particles of virion-containing respiratory fluids are likely important to effectively designing and using UV germicidal irradiation systems for microbes in particles. The results suggest the use of reflective surfaces to increase the angles of illumination and decrease the Sp. The results suggest the need for measurements of the Sp of SARS-CoV-2 in particles having compositions and sizes relevant to the modes of disease transmission.
Subject(s)
Bodily Secretions/radiation effects , Bodily Secretions/virology , SARS-CoV-2/radiation effects , Ultraviolet Rays , Virion/radiation effects , Aerosols , Air Microbiology , COVID-19/virology , Computer Simulation , Cough/virology , Disinfection/methods , Humans , SneezingABSTRACT
Circulating nucleic acids, encapsulated within small extracellular vesicles (EVs), provide a remote cellular snapshot of biomarkers derived from diseased tissues, however selective isolation is critical. Current laboratory-based purification techniques rely on the physical properties of small-EVs rather than their inherited cellular fingerprints. We established a highly-selective purification assay, termed EV-CATCHER, initially designed for high-throughput analysis of low-abundance small-RNA cargos by next-generation sequencing. We demonstrated its selectivity by specifically isolating and sequencing small-RNAs from mouse small-EVs spiked into human plasma. Western blotting, nanoparticle tracking, and transmission electron microscopy were used to validate and quantify the capture and release of intact small-EVs. As proof-of-principle for sensitive detection of circulating miRNAs, we compared small-RNA sequencing data from a subset of small-EVs serum-purified with EV-CATCHER to data from whole serum, using samples from a small cohort of recently hospitalized Covid-19 patients. We identified and validated, only in small-EVs, hsa-miR-146a and hsa-miR-126-3p to be significantly downregulated with disease severity. Separately, using convalescent sera from recovered Covid-19 patients with high anti-spike IgG titers, we confirmed the neutralizing properties, against SARS-CoV-2 in vitro, of a subset of small-EVs serum-purified by EV-CATCHER, as initially observed with ultracentrifuged small-EVs. Altogether our data highlight the sensitivity and versatility of EV-CATCHER.
Subject(s)
Extracellular Vesicles/chemistry , Immunologic Techniques/methods , Animals , Bodily Secretions/chemistry , COVID-19/blood , COVID-19/physiopathology , Chlorocebus aethiops , Circulating MicroRNA , High-Throughput Nucleotide Sequencing , Humans , MCF-7 Cells , Mice , RAW 264.7 Cells , Severity of Illness Index , Vero CellsABSTRACT
The main purpose of this study is to evaluate the presence of viral RNA of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in conjunctival swab specimen of coronavirus disease 2019 (COVID-19) patients with and without conjunctivitis to establish the diagnostic value of reverse transcription-polymerase chain reaction (RT-PCR) in each case and to describe its clinical characteristics. A cross-sectional study was conducted at the Hospital Clinico San Carlos of Madrid, Spain. Thirty-six subjects from the COVID admission unit with laboratory-confirmed SARS-CoV-2 infection were included. Conjunctival swabs were collected from 18 patients with conjunctivitis and 18 patients without conjunctivitis and RT-PCR was performed. Conjunctival swab was collected from both eyes of 36 patients (72 eyes), detecting SARS-CoV-2 RNA in conjunctival swab of two patients (5.5%). Among the 18 patients with conjunctivitis, only one of them (5.5%) showed positive results. Likewise, SARS-CoV-2 RNA was detected in one patient without conjunctivitis (5.5%). The mean age of the 36 patients was 67.9 years (range, 28-92 years) and the male-to-female ratio was 0.44 (16:20). The mean days since the onset of COVID-19 symptoms until conjunctivitis manifestation was 8 (range, 1-24 days). The mean duration of the conjunctivitis was 3 days (range, 1-7 days). SARS-CoV-2 RNA may be detected in conjunctival swabs of both patients with and without conjunctivitis. This study revealed the same rate of positive results amongst the group with and without conjunctivitis, suggesting that detecting SARS-CoV-2 in ocular fluids is not conditioned on the presence of conjunctivitis. The presence of SARS-CoV-2 RNA in ocular samples highlights the role of the eye as a possible route of transmission of the disease.
Subject(s)
Bodily Secretions/virology , COVID-19/diagnosis , Conjunctiva/chemistry , Conjunctivitis, Viral/physiopathology , RNA, Viral/analysis , Adult , Aged , Aged, 80 and over , COVID-19/virology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Spain , Specimen HandlingABSTRACT
BACKGROUND: Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) play a critical role in neurodevelopment, where breast milk is a significant dietary source. The impact of previous COVID-19 infection and mastitis on the concentration of BDNF and NGF in human milk was investigated. METHODS: Concentrations of BDNF and NGF were measured via ELISA in human milk samples collected from 12 mothers with a confirmed COVID-19 PCR, 13 mothers with viral symptoms suggestive of COVID-19, and 22 unexposed mothers (pre-pandemic Ctl-2018). These neurotrophins were also determined in 12 mothers with previous mastitis and 18 mothers without mastitis. RESULTS: The NGF concentration in human milk was lower in the COVID-19 PCR and viral symptoms groups than in the unexposed group, but BDNF did not differ significantly. Within the COVID-19 group, BDNF was higher in mothers who reported headaches or loss of smell/taste when compared with mothers without the respective symptom. BDNF was lower in mothers with mastitis than in mothers without mastitis. CONCLUSIONS: Previous COVID-19 and mastitis infections changed differently the secretion of NGF and BDNF in human milk. Whether the changes in NGF and BDNF levels in milk from mothers with infection influence their infant's development remains to be investigated.
Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , COVID-19/metabolism , Mastitis/metabolism , Milk, Human/chemistry , Nerve Growth Factor/metabolism , Adult , Bodily Secretions/chemistry , Brain-Derived Neurotrophic Factor/analysis , COVID-19/complications , Female , Humans , Mastitis/complications , Mothers , Nerve Growth Factor/analysisABSTRACT
This study compares nasopharyngeal and tracheal samples for COVID-19 viral testing in patients with a tracheostomy. This was a prospective cohort study done at 2 academic hospitals between March and June 2020. Patients admitted through the emergency department who had a COVID-19 test and an existing tracheostomy or underwent a tracheostomy during the admission period were included. Patients with a positive initial nasopharyngeal swab were placed in the experimental group (n = 8), while those with a negative swab were the control group (n = 7). Nasopharyngeal and tracheal samples underwent COVID-19 testing using the Abbott RealTime SARS-CoV-2 RNA assay. Fourteen patients underwent tracheostomy, and 1 had an existing tracheostomy. The average duration of viral shedding in nasopharyngeal samples was 20.9 days. One patient (6.7%) tested positive in tracheal secretions after a negative nasopharyngeal swab. In the remaining patients (93.3%), the nasopharyngeal and tracheal specimens correlated.
Subject(s)
Bodily Secretions/chemistry , COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Nose , Pharynx , RNA, Viral/analysis , SARS-CoV-2/genetics , Trachea , Adult , Aged , COVID-19/therapy , Female , Humans , Male , Middle Aged , Prospective Studies , TracheostomyABSTRACT
Due to the cellular entry of the novel coronavirus (SARS-CoV-2) modulated by angiotensin converting enzyme 2 (ACE2), the ACE2 bearing prostate is therefore hypothesized as a susceptible organ to COVID-19. To delineate whether the pathogenic SARS-CoV-2 of the coronavirus disease (COVID-19) could be detected in the expressed prostatic secretion (EPS), a total of ten male patients with confirmed COVID-19 were recruited. All patients were stratified into two groups: one group with positive nasopharyngeal swabbing SARS-CoV-2 within 3 days of the EPS taken day (PNS group, n = 3) and the other group with previously positive nasopharyngeal swabbing SARS-CoV-2 but turned negative before the taken day (PNNS group, n = 7). The COVID-19 patients showed elevated inflammatory indictors, i.e. C-reaction protein (3.28 (1.14, 33.33) mg/L), erythrocyte sedimentation rate (22.50 (8.00, 78.50) mm/h), and interleukin-6 (6.49 (4.96, 21.09) pg/ml). Serum IgM against SARS-CoV-2 was only positive in the PNS group, whereas serum IgG was positive for all patients. Furthermore, our data showed for the first time that none of the COVID-19 patients had positive SARS-CoV-2 RNA in EPS. To this end, this study found the negativity of SARS-CoV-2 in EPS and possibly exclude the sexual transmission of COVID-19.
Subject(s)
Bodily Secretions/virology , COVID-19/virology , Prostate/virology , SARS-CoV-2/isolation & purification , Adult , Aged , Antibodies, Viral/blood , COVID-19/blood , COVID-19/diagnosis , COVID-19/transmission , COVID-19 Nucleic Acid Testing , COVID-19 Serological Testing , China , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Inflammation Mediators/blood , Male , Middle Aged , RNA, Viral/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/immunologyABSTRACT
The influenza virus and SARS-CoV-2 cause trivial upper and severe lower respiratory infections (Influenza virus 290,000 to 650,000 deaths/year). These viruses come into contact with the airways either by direct projection, by secondary inhalation of airborne droplets, or by handling (fomites). The objective of this article is to clarify the mechanisms of production and penetration of droplets of secretions emitted during all expiratory phenomena likely to transport these viruses and come into contact with the respiratory mucosa. The droplets>5µm follow the laws of ballistics, those<5µm follow Brownian motion and remain suspended in the air. The aerosols of droplets are very heterogeneous whether the subject is healthy or sick. During an infectious period, not all droplets contain viral RNA. If these RNAs are detectable around patients, on surfaces, and in the ambient air at variable distances according to the studies (from 0.5m to beyond the patient's room), this is without prejudice to the infectious nature (viability) of the virus and the minimum infectious dose. There is a time lag between the patient's infectious period and that of RNA detection for both viruses. Subsequently, the inhaled particles must meet the laws of fluid dynamics (filtration) to settle in the respiratory tree. All of this partly explains the contagiousness and the clinical expression of these two viruses from the olfactory cleft to the alveoli.
Subject(s)
Betacoronavirus/pathogenicity , Bodily Secretions/virology , Coronavirus Infections/transmission , Influenza, Human/transmission , Orthomyxoviridae/pathogenicity , Otolaryngology , Pneumonia, Viral/transmission , Respiratory Mucosa/virology , Aerosols , Betacoronavirus/genetics , COVID-19 , Humans , Orthomyxoviridae/genetics , Pandemics , RNA, Viral/analysis , SARS-CoV-2ABSTRACT
BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spread mainly through respiratory droplets or direct contact. However, the infection condition of the genital system is unknown. Our aim in this study was to determine if SARS-CoV-2 is present in the vaginal fluid of women with coronavirus disease 2019 (COVID-19). METHODS: Ten women with confirmed severe COVID-19 pneumonia admitted to the Tongji Zhongfa Hospital intensive care unit from 4 February 2020 through 24 February 2020 were included. Clinical records, laboratory results, and computed tomography examinations were retrospectively reviewed. The potential for genital infection was accessed by testing for the presence of SARS-CoV-2 in vaginal fluids obtained from vaginal swab samples. Reverse transcriptase polymerase chain reaction was used to confirm the SARS-CoV-2 infection in vaginal fluids. RESULTS: The clinical characteristics of the 10 women were similar to those reported in other severe COVID-19 patients. All 10 patients were tested for SARS-CoV-2 in vaginal fluid, and all samples tested negative for the virus. CONCLUSIONS: Findings from this small group of cases suggest that SARS-CoV-2 virus does not exist in the vaginal fluids of severe COVID-19 patients.
Subject(s)
Bodily Secretions/virology , Body Fluids/virology , Coronavirus Infections/diagnosis , Coronavirus Infections/virology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/virology , Vagina/virology , Betacoronavirus/genetics , COVID-19 , Female , Humans , Pandemics , Retrospective Studies , SARS-CoV-2 , Severe Acute Respiratory Syndrome/virologyABSTRACT
OBJECTIVE: This study aimed to assess the presence of novel coronavirus in tears and conjunctival secretions of SARS-CoV-2-infected patients. METHODS: A prospective interventional case series study was performed, and 30 confirmed novel coronavirus pneumonia (NCP) patients were selected at the First Affiliated Hospital of Zhejiang University from 26 January 2020 to 9 February 2020. At an interval of 2 to 3 days, tear and conjunctival secretions were collected twice with disposable sampling swabs for reverse-transcription polymerase chain reaction (RT-PCR) assay. RESULTS: Twenty-one common-type and nine severe-type NCP patients were enrolled. Two samples of tear and conjunctival secretions were obtained from the only one patient with conjunctivitis yielded positive RT-PCR results. Fifty-eight samples from other patents were all negative. CONCLUSION: We speculate that SARS-CoV-2 may be detected in the tears and conjunctival secretions in NCP patients with conjunctivitis.