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1.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34465564

RESUMO

After the Spanish flu pandemic, it was apparent that airborne transmission was crucial to spreading virus contagion, and research responded by producing several fundamental works like the experiments of Duguid [J. P. Duguid, J. Hyg. 44, 6 (1946)] and the model of Wells [W. F. Wells, Am. J. Hyg. 20, 611-618 (1934)]. These seminal works have been pillars of past and current guidelines published by health organizations. However, in about one century, understanding of turbulent aerosol transport by jets and plumes has enormously progressed, and it is now time to use this body of developed knowledge. In this work, we use detailed experiments and accurate computationally intensive numerical simulations of droplet-laden turbulent puffs emitted during sneezes in a wide range of environmental conditions. We consider the same emission-number of drops, drop size distribution, and initial velocity-and we change environmental parameters such as temperature and humidity, and we observe strong variation in droplets' evaporation or condensation in accordance with their local temperature and humidity microenvironment. We assume that 3% of the initial droplet volume is made of nonvolatile matter. Our systematic analysis confirms that droplets' lifetime is always about one order of magnitude larger compared to previous predictions, in some cases up to 200 times. Finally, we have been able to produce original virus exposure maps, which can be a useful instrument for health scientists and practitioners to calibrate new guidelines to prevent short-range airborne disease transmission.


Assuntos
COVID-19/transmissão , Guias como Assunto , Aerossóis , Biologia Computacional , Simulação por Computador , Humanos , Exposição por Inalação , Medição de Risco , Espirro
2.
Sci Rep ; 11(1): 16051, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362974

RESUMO

With an increasing body of evidence that SARS-CoV-2 is an airborne pathogen, droplet character formed during speech, coughs, and sneezes are important. Larger droplets tend to fall faster and are less prone to drive the airborne transmission pathway. Alternatively, small droplets (aerosols) can remain suspended for long time periods. The small size of SARS-CoV-2 enables it to be encapsulated in these aerosols, thereby increasing the pathogen's ability to be transmitted via airborne paths. Droplet formation during human respiratory events relates to airspeed (speech, cough, sneeze), fluid properties of the saliva/mucus, and the fluid content itself. In this work, we study the fluidic drivers (fluid properties and content) and their influence on factors relating to transmissibility. We explore the relationship between saliva fluid properties and droplet airborne transmission paths. Interestingly, the natural human response appears to potentially work with these drivers to mitigate pathogen transmission. In this work, the saliva is varied using two approaches: (1) modifying the saliva with colloids that increase the viscosity/surface tension, and (2) stimulating the saliva content to increased/decreased levels. Through modern experimental and numerical flow diagnostic methods, the character, content, and exposure to droplets and aerosols are all evaluated. The results indicate that altering the saliva properties can significantly impact the droplet size distribution, the formation of aerosols, the trajectory of the bulk of the droplet plume, and the exposure (or transmissibility) to droplets. High-fidelity numerical methods used and verify that increased droplet size character enhances droplet fallout. In the context of natural saliva response, we find previous studies indicating natural human responses of increased saliva viscosity from stress and reduced saliva content from either stress or illness. These responses both favorably correspond to reduced transmissibility. Such a finding also relates to potential control methods, hence, we compared results to a surgical mask. In general, we find that saliva alteration can produce fewer and larger droplets with less content and aerosols. Such results indicate a novel approach to alter SARS-CoV-2's transmission path and may act as a way to control the COVID-19 pandemic, as well as influenza and the common cold.


Assuntos
COVID-19/transmissão , SARS-CoV-2/isolamento & purificação , Saliva/virologia , Aerossóis/química , Microbiologia do Ar , Coloides/química , Tosse , Humanos , Pandemias , Saliva/química , Espirro , Viscosidade
3.
Nat Rev Neurosci ; 22(8): 455, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34226717

Assuntos
Espirro , Humanos
4.
BMJ Case Rep ; 14(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253526

RESUMO

Pneumolabyrinth refers to the presence of air within the inner ear and is a fairly common occurrence immediately after stapes surgery, but rarely occurs in a delayed manner years after the initial operation. We present a case of a patient with a history of left stapedotomy 15 years prior, who presented with acute onset vertigo, tinnitus and hearing loss in her operated ear. Her symptoms were preceded by an upper respiratory tract infection associated with bouts of sneezing. Examination revealed a spontaneous right beating nystagmus and positive head thrust to the left. Pure tone audiometry demonstrated a left mixed hearing loss which subsequently deteriorated to a profound sensorineural hearing loss. CT showed the presence of air within the left vestibule and semicircular canals. The patient underwent an exploratory tympanotomy and repair of perilymphatic leak with resolution of vestibular symptoms but no improvement in sensorineural hearing thresholds.


Assuntos
Doenças do Labirinto , Cirurgia do Estribo , Audiometria de Tons Puros , Orelha Média , Feminino , Humanos , Doenças do Labirinto/cirurgia , Espirro , Cirurgia do Estribo/efeitos adversos , Vertigem/etiologia
5.
J Intern Med ; 290(5): 1010-1027, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34105202

RESUMO

The SARS-CoV-2 virus is highly contagious, as demonstrated by numerous well-documented superspreading events. The infection commonly starts in the upper respiratory tract (URT) but can migrate to the lower respiratory tract (LRT) and other organs, often with severe consequences. Whereas LRT infection can lead to shedding of virus via breath and cough droplets, URT infection enables shedding via abundant speech droplets. Their viral load can be high in carriers with mild or no symptoms, an observation linked to the abundance of SARS-CoV-2-susceptible cells in the oral cavity epithelium. Expelled droplets rapidly lose water through evaporation, with the smaller ones transforming into long-lived aerosol. Although the largest speech droplets can carry more virions, they are few in number, fall to the ground rapidly and therefore play a relatively minor role in transmission. Of more concern is small speech aerosol, which can descend deep into the LRT and cause severe disease. However, since their total volume is small, the amount of virus they carry is low. Nevertheless, in closed environments with inadequate ventilation, they can accumulate, which elevates the risk of direct LRT infection. Of most concern is the large fraction of speech aerosol that is intermediate-sized because it remains suspended in air for minutes and can be transported over considerable distances by convective air currents. The abundance of this speech-generated aerosol, combined with its high viral load in pre- and asymptomatic individuals, strongly implicates airborne transmission of SARS-CoV-2 through speech as the primary contributor to its rapid spread.


Assuntos
COVID-19/epidemiologia , Tosse/etiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , SARS-CoV-2/genética , Espirro , Carga Viral , COVID-19/complicações , Saúde Global , Humanos , Pandemias
6.
Eur J Med Res ; 26(1): 52, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108042

RESUMO

BACKGROUND: We are laryngologists. We observe natural phonatory and swallowing functions in clinical examinations with a trans-nasal laryngeal fiberscope (TNLF). Before each observation, we use epinephrine to enlarge and smooth the common nasal meatus (bottom of nostril) and then insert a wet swab inside the nose, as in taking a swab culture in the nasopharynx. During the current COVID-19 pandemic situation, this careful technique prevents any complications, including nasal bleeding, painfulness, and induced sneezing. Here, we introduce our routine to observe esophageal movement in swallowing in a natural (sitting) position without anesthesia. CASE PRESENTATION: The case was a 70-year-old female who complained that something was stuck in her esophagus; there was a strange sensation below the larynx and pharynx. After enlarging and smoothing the common nasal meatus, we inserted the TNLF (slim type ⌀2.9 mm fiberscope, VNL8-J10, PENTAX Medical, Tokyo, Japan.) in the normal way. We then observed the phonatory and swallowing movements of the vocal folds. As usual, to not interfere with natural movements, we used no anesthesia. We found no pathological condition in the pyriform sinus. We asked the patient to swallow the fiberscope. During the swallow, we pushed the TNLF and inserted the tip a bit deeper, which made the fiberscope easily enter the esophagus, like in the insertion of a nasogastric tube. We then asked the patient to swallow a sip of water or saliva to clear and enlarge the lumen of the esophagus. This made it possible to observe the esophagus easily without any air supply. With tone enhancement scan, the esophagus was found to be completely normal except for glycogenic acanthosis. CONCLUSIONS: The advantage of this examination is that it is easily able to perform without anesthesia and with the patient in sitting position. It is quick and minimally invasive, enabling observation the physiologically natural swallowing. It is also possible to observe without anesthesia down to the level of the esophagogastric junction using with a thin type flexible bronchoscope. In the future, gastric fiberscopes might be thinner, even with narrow band imaging (NBI) function. Before that time, physicians should remember to just insert along the bottom of the nose.


Assuntos
COVID-19/prevenção & controle , Esôfago/metabolismo , Glicogênio/metabolismo , Intubação Intratraqueal/métodos , Idoso , Anestesia , COVID-19/epidemiologia , COVID-19/virologia , Epitélio/metabolismo , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Membrana Mucosa/metabolismo , Cavidade Nasal , Pandemias , Reprodutibilidade dos Testes , SARS-CoV-2/fisiologia , Espirro
7.
J Occup Environ Hyg ; 18(8): 394-408, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34161194

RESUMO

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.


Assuntos
Secreções Corporais/efeitos da radiação , Secreções Corporais/virologia , SARS-CoV-2/efeitos da radiação , Raios Ultravioleta , Vírion/efeitos da radiação , Aerossóis , Microbiologia do Ar , COVID-19/virologia , Simulação por Computador , Tosse/virologia , Desinfecção/métodos , Humanos , Espirro
8.
Sci Rep ; 11(1): 12110, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103573

RESUMO

Wearing surgical masks or other similar face coverings can reduce the emission of expiratory particles produced via breathing, talking, coughing, or sneezing. Although it is well established that some fraction of the expiratory airflow leaks around the edges of the mask, it is unclear how these leakage airflows affect the overall efficiency with which masks block emission of expiratory aerosol particles. Here, we show experimentally that the aerosol particle concentrations in the leakage airflows around a surgical mask are reduced compared to no mask wearing, with the magnitude of reduction dependent on the direction of escape (out the top, the sides, or the bottom). Because the actual leakage flowrate in each direction is difficult to measure, we use a Monte Carlo approach to estimate flow-corrected particle emission rates for particles having diameters in the range 0.5-20 µm. in all orientations. From these, we derive a flow-weighted overall number-based particle removal efficiency for the mask. The overall mask efficiency, accounting both for air that passes through the mask and for leakage flows, is reduced compared to the through-mask filtration efficiency, from 93 to 70% for talking, but from only 94-90% for coughing. These results demonstrate that leakage flows due to imperfect sealing do decrease mask efficiencies for reducing emission of expiratory particles, but even with such leakage surgical masks provide substantial control.


Assuntos
Aerossóis , Controle de Doenças Transmissíveis/métodos , Tosse , Expiração , Filtração , Máscaras , Viroses/prevenção & controle , Adolescente , Adulto , COVID-19/prevenção & controle , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Tamanho da Partícula , Probabilidade , Respiração , Espirro , Adulto Jovem
9.
BMJ Case Rep ; 14(5)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059530

RESUMO

A 47-year-old woman presented to the emergency department with sudden onset of swelling in her face, which had been triggered by blowing her nose. She had no other symptoms, but was known to have Ehlers-Danlos syndrome. A CT confirmed bilateral subcutaneous facial emphysema attributed to a defect in her left nasal cartilage. The condition was managed conservatively with prophylactic antibiotics and self-resolved within 48 hours. Only eight cases of sudden facial subcutaneous emphysema following nose blowing or sneezing have been found in the English literature and this is the first known case in a patient with a connective tissue disorder. In this case, her condition is suspected to have contributed to her presentation and may be underlying in other similar cases.


Assuntos
Síndrome de Ehlers-Danlos , Enfisema Subcutâneo , Tecido Conjuntivo , Feminino , Humanos , Pessoa de Meia-Idade , Nariz , Espirro , Enfisema Subcutâneo/diagnóstico por imagem , Enfisema Subcutâneo/etiologia
10.
Sci Rep ; 11(1): 9826, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972590

RESUMO

High-fidelity simulations of coughs and sneezes that serve as virtual experiments are presented, and they offer an unprecedented opportunity to peer into the chaotic evolution of the resulting airborne droplet clouds. While larger droplets quickly fall-out of the cloud, smaller droplets evaporate rapidly. The non-volatiles remain airborne as droplet nuclei for a long time to be transported over long distances. The substantial variation observed between the different realizations has important social distancing implications, since probabilistic outlier-events do occur and may need to be taken into account when assessing the risk of contagion. Contrary to common expectations, we observe dry ambient conditions to increase by more than four times the number of airborne potentially virus-laden nuclei, as a result of reduced droplet fall-out through rapid evaporation. The simulation results are used to validate and calibrate a comprehensive multiphase theory, which is then used to predict the spread of airborne nuclei under a wide variety of ambient conditions.


Assuntos
COVID-19/transmissão , Tosse/virologia , Modelos Biológicos , SARS-CoV-2/patogenicidade , Espirro , Microbiologia do Ar , COVID-19/virologia , Simulação por Computador , Humanos , Umidade
11.
Sci Rep ; 11(1): 9412, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941805

RESUMO

The spread of the novel coronavirus disease (COVID-19) continues to show that geographic barriers alone cannot contain the virus. Asymptomatic carriers play a critical role in the nature of this virus, which is rapidly escalating into a global pandemic. Asymptomatic carriers can inadvertently transmit the virus through the air stream. Many diseases can infect human bodies with tiny droplets or particles that carry various viruses and bacteria that are generated by the respiratory system of infected patients. This article presents the numerical results of the spread of droplets or particles in a room. The proposed numerical model in this work takes into account the sedimentation of particles or droplets under the action of gravitational sedimentation and transport in the room during the process of breathing and sneezing or coughing. Three different cases are numerically investigated taking into account normal breathing and coughing or sneezing, respectively, and three different rates of particle ejection from the mouth are considered. Navier-Stokes equations for incompressible flows were used to describe three-dimensional air flow inside ventilated rooms. The influence of ventilation rate on social distancing is also computationally investigated. It was found that particles can move up to 5 m with a decrease in concentration in the direction of the air flow. The conclusions made in this work show that, given the environmental conditions, the two meter social distance recommended by WHO is insufficient.


Assuntos
Microbiologia do Ar , COVID-19/prevenção & controle , COVID-19/transmissão , Tosse , Expiração , Espirro , Humanos , Modelos Teóricos , Pandemias , Tamanho da Partícula , Distanciamento Físico , SARS-CoV-2
12.
Infect Dis Now ; 51(3): 219-227, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33934808

RESUMO

The novel human coronavirus SARS-CoV-2 has been responsible for a worldwide pandemic. Although media transmission through contaminated surfaces is one of the most recognized ways of transmission, the study on the number and viability of viruses surviving on a surface after leaving the host represents a "blind spot" in current research. In this paper we have reviewed studies on the physical process of droplet evaporation on media surfaces, and analyzed the recent literature related to experiments on the decay of the viral concentration and infectious activity of SARS-CoV-2 and other viruses on those surface and in the air. The huge differences in the risk of media transmission of large saliva and sputum droplets were analyzed in terms of time elapsed. Due to the rapid decrease of water content in the evaporated droplets and the increased concentration of each component, the living environment of the virus tended to deteriorate sharply, and virus concentration plummeted within a few minutes. Although a virus can be detected in a matter of hours, tens of hours, or days, the risk of transmission is negligible compared to when it first left the host. This study suggests that the key to prevention and control is to start from the source, the earlier the better. It is extremely important to develop good public health habits, wear masks, and wash hands frequently. That said, excessive disinfection and sterilization of surfaces during a later period may have adverse effects.


Assuntos
COVID-19/transmissão , Transmissão de Doença Infecciosa , Muco/virologia , SARS-CoV-2/fisiologia , Saliva/virologia , Escarro/virologia , Fenômenos Fisiológicos Virais , Microbiologia do Ar , Bactérias/isolamento & purificação , COVID-19/virologia , Tosse , Dessecação , Transmissão de Doença Infecciosa/prevenção & controle , Contaminação de Equipamentos , Fômites , Humanos , Umidade , Higiene , Tamanho da Partícula , Respiração , Risco , SARS-CoV-2/isolamento & purificação , Espirro , Fala , Temperatura , Fatores de Tempo , Carga Viral , Vírus/isolamento & purificação
13.
Environ Health Perspect ; 129(4): 47002, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33793301

RESUMO

BACKGROUND: Evidence for indoor airborne transmission of SARS-CoV-2 is accumulating. OBJECTIVES: We assessed of the risk of illness due to airborne SARS-CoV-2 particles from breathing, speaking, singing, coughing, and sneezing in indoor environments. METHODS: A risk assessment model, AirCoV2, for exposure to SARS-CoV-2 particles in aerosol droplets was developed. Previously published data on droplets expelled by breathing, speaking, singing, coughing, and sneezing by an infected person were used as inputs. Scenarios encompassed virus concentration, exposure time, and ventilation. Newly collected data of virus RNA copies in mucus from patients are presented. RESULTS: The expelled volume of aerosols was highest for a sneeze, followed by a cough, singing, speaking, and breathing. After 20 min of exposure, at 107 RNA copies/mL in mucus, all mean illness risks were largely estimated to be below 0.001, except for the "high" sneeze scenario. At virus concentrations above 108 RNA copies/mL, and after 2 h of exposure, in the high and "low" sneeze scenarios, the high cough scenario and the singing scenario, risks exceeded 0.01 and may become very high, whereas the low coughing scenario, the high and low speaking scenarios and the breathing scenario remained below 0.1. After 2 h of exposure, singing became the second highest risk scenario. One air exchange per hour reduced risk of illness by about a factor of 2. Six air exchanges per hour reduced risks of illness by a factor of 8-13 for the sneeze and cough scenarios and by a factor of 4-9 for the other scenarios. DISCUSSION: The large variation in the volume of expelled aerosols is discussed. The model calculations indicated that SARS-CoV-2 transmission via aerosols outside of the 1.5-m social distancing norm can occur. Virus concentrations in aerosols and/or the amount of expelled aerosol droplets need to be high for substantial transmission via this route. AirCoV2 is made available as interactive computational tool. https://doi.org/10.1289/EHP7886.


Assuntos
Aerossóis , COVID-19/transmissão , Pandemias/prevenção & controle , Medição de Risco/métodos , SARS-CoV-2 , Microbiologia do Ar , COVID-19/prevenção & controle , Tosse , Transmissão de Doença Infecciosa , Humanos , Canto , Espirro
14.
Molecules ; 26(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804078

RESUMO

Sneezing (sternutatio) is a poorly understood polysynaptic physiologic reflex phenomenon. Sneezing has exerted a strange fascination on humans throughout history, and induced sneezing was widely used by physicians for therapeutic purposes, on the assumption that sneezing eliminates noxious factors from the body, mainly from the head. The present contribution examines the various mixtures used for inducing sneezes (remedia sternutatoria) over the centuries. The majority of the constituents of the sneeze-inducing remedies are modulators of transient receptor potential (TRP) channels. The TRP channel superfamily consists of large heterogeneous groups of channels that play numerous physiological roles such as thermosensation, chemosensation, osmosensation and mechanosensation. Sneezing is associated with the activation of the wasabi receptor, (TRPA1), typical ligand is allyl isothiocyanate and the hot chili pepper receptor, (TRPV1), typical agonist is capsaicin, in the vagal sensory nerve terminals, activated by noxious stimulants.


Assuntos
Espirro/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Capsaicina/farmacologia , Humanos , Espirro/efeitos dos fármacos , Canais de Potencial de Receptor Transitório/efeitos dos fármacos
15.
Infez Med ; 29(1): 10-19, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33664169

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pandemic worldwide. On a daily basis the number of deaths associated with COVID-19 is rapidly increasing. The main transmission route of SARS-CoV-2 is through the air (airborne transmission). This review details the airborne transmission of SARS-CoV-2, the aerodynamics, and different modes of transmission (e.g. droplets, droplet nuclei, and aerosol particles). SARS-CoV-2 can be transmitted by an infected person during activities such as expiration, coughing, sneezing, and talking. During such activities and some medical procedures, aerosols and droplets contaminated with SARS-CoV-2 particles are formed. Depending on their sizes and the environmental conditions, such particles stay viable in the air for varying time periods and can cause infection in a susceptible host. Very few studies have been conducted to establish the mechanism or the aerodynamics of virus-loaded particles and droplets in causing infection. In this review we discuss the various forms in which SARS-CoV-2 virus particles can be transmitted in air and cause infections.


Assuntos
Microbiologia do Ar , COVID-19/transmissão , SARS-CoV-2 , Número Básico de Reprodução/estatística & dados numéricos , COVID-19/prevenção & controle , Tosse/virologia , Exposição Ambiental , Humanos , Máscaras , Espirro
16.
Sci Rep ; 11(1): 3953, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597564

RESUMO

Contact and inhalation of virions-carrying human aerosols represent the primary transmission pathway for airborne diseases including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Relative to sneezing and coughing, non-symptomatic aerosol-producing activities such as speaking are highly understudied. The dispersions of aerosols from vocalization by a human subject are hereby quantified using high-speed particle image velocimetry. Syllables of different aerosol production rates were tested and compared to coughing. Results indicate aerosol productions and penetrations are not correlated. E.g. 'ti' and 'ma' have similar production rates but only 'ti' penetrated as far as coughs. All cases exhibited a rapidly penetrating "jet phase" followed by a slow "puff phase." Immediate dilution of aerosols was prevented by vortex ring flow structures that concentrated particles toward the plume-front. A high-fidelity assessment of risks to exposure must account for aerosol production rate, penetration, plume direction and the prevailing air current.


Assuntos
Aerossóis/análise , COVID-19/transmissão , SARS-CoV-2/química , Fala/fisiologia , Adulto , Aerossóis/química , COVID-19/virologia , Tosse , Humanos , Masculino , Tamanho da Partícula , Reologia/métodos , SARS-CoV-2/patogenicidade , Espirro , Comportamento Verbal/fisiologia
18.
J Laryngol Otol ; 135(2): 142-146, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33494850

RESUMO

BACKGROUND: Laryngopharyngeal reflux symptoms assessed with the reflux symptom index can overlap with non-allergic rhinitis symptoms. This study aims to explore the association between the reflux symptom index and nasal symptoms in non-allergic rhinitis patients. METHODS: A cross-sectional study was conducted on consecutive adults with non-allergic rhinitis. The reflux symptom index (score of more than 13 = laryngopharyngeal reflux) and nasal symptoms (categorised as mild (total score of 0-3), moderate (4-7) or severe (8-12)) were assessed. RESULTS: The study included 227 participants (aged 58.64 ± 12.39 years, 59.5 per cent female). The reflux symptom index scores increased with total nasal symptom scores (mild vs moderate vs severe, 8.61 ± 6.27 vs 12.94 ± 7.4 vs 16.40 ± 8.10; p < 0.01). Logistic regression indicated that laryngopharyngeal reflux is more likely in patients with severe nose block (odds ratio 5.47 (95 per cent confidence interval = 2.16-13.87); p < 0.01). CONCLUSION: Laryngopharyngeal reflux symptoms are associated with nasal symptom severity, and nasal symptoms should be primarily treated. Those with predominant nose block and laryngopharyngeal reflux symptoms are more likely to have laryngopharyngeal reflux.


Assuntos
Refluxo Laringofaríngeo/etiologia , Doenças Nasais/complicações , Rinite/complicações , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Refluxo Laringofaríngeo/diagnóstico , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/epidemiologia , Doenças Nasais/diagnóstico , Rinorreia/epidemiologia , Índice de Gravidade de Doença , Espirro
19.
Am J Otolaryngol ; 42(3): 102888, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33460980

RESUMO

PURPOSE: Due to the COVID-19 pandemic, aerosol-generating procedures (AGPs) such as flexible endoscopic evaluation of swallowing (FEES) have been deemed high-risk and in some cases restricted, indicating the need for additional personal protective equipment. The aim of this study was to erect and study a protective barrier for FEES. MATERIALS AND METHODS: A PVC cube was constructed to fit over a patient while allowing for upright endoscopy. A plastic drape was fitted over the cube, and the protective barrier was subsequently named the "FEES Box." Three different particulate-generating tasks were carried out: sneezing, coughing, and spraying water from an atomizer bottle. Each task was completed within and without the FEES Box, and particulate was measured with a particle counter. The average particles/L detected during the three tasks, and baseline measurements, were statistically compared. RESULTS: Without the FEES Box in place, the sneezing and spraying tasks resulted in a statistically significant increase in particles above baseline (p < 0.001 and p = 0.004, respectively); coughing particulate never reached levels significantly higher than baseline (p = 0.230). With use of the FEES Box, there was no statistically significant increase in particles above baseline in any of the three tasks. CONCLUSION: The FEES Box effectively contained particles generated during sneezes and an atomizer spray. It would also likely mitigate coughing particulate, but coughing did not generate a significant increase in particles above baseline. Further research is warranted to test the efficacy of the FEES Box in containing particulate matter during a complete FEES procedure.


Assuntos
Aerossóis/análise , COVID-19/prevenção & controle , Controle de Infecções/instrumentação , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Laringoscopia/efeitos adversos , Equipamento de Proteção Individual , Tosse , Desenho de Equipamento , Humanos , Material Particulado/análise , SARS-CoV-2 , Espirro
20.
Int J Sports Med ; 42(5): 407-418, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33511617

RESUMO

A review of risk factors affecting airborne transmission of SARS-CoV-2 was synthesised into an 'easy-to-apply' visual framework. Using this framework, video footage from two cricket matches were visually analysed, one pre-COVID-19 pandemic and one 'COVID-19 aware' game in early 2020. The number of opportunities for one participant to be exposed to biological secretions belonging to another participant was recorded as an exposure, as was the estimated severity of exposure as defined from literature. Events were rated based upon distance between subjects, relative orientation of the subjects, droplet generating activity performed (e. g., talking) and event duration. In analysis we reviewed each risk category independently and the compound effect of an exposure i. e., the product of the scores across all categories. With the application of generic, non-cricket specific, social distancing recommendations and general COVID-19 awareness, the number of exposures per 100 balls was reduced by 70%. More impressive was the decrease in the most severe compound ratings (those with two or more categories scored with the highest severity) which was 98% and the reduction in exposures with a proximity <1 m, 96%. Analysis of the factors effecting transmission risk indicated that cricket was likely to present a low risk, although this conclusion was somewhat arbitrary omitting a comparison with a non-cricketing activity.


Assuntos
Microbiologia do Ar , COVID-19/transmissão , Críquete , Distanciamento Físico , Aerossóis , Tosse/virologia , Exposição Ambiental , Humanos , Pandemias , Respiração , Fatores de Risco , SARS-CoV-2 , Espirro , Interação Social
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