Respiratory Aerosols Research Articles

Highly Adsorptive Au-TiO2 Nanocomposites for the SERS Face Mask Allow the Machine-Learning-Based Quantitative Assay of SARS-CoV-2 in Artificial Breath Aerosols.

Human respiratory aerosols contain diverse potential biomarkers for early disease diagnosis. Here, we report the direct and label-free detection of SARS-CoV-2 in respiratory aerosols using a highly adsorptive Au-TiO2 nanocomposite SERS face mask and an ablation-assisted autoencoder. The Au-TiO2 SERS face mask continuously preconcentrates and efficiently captures the oronasal aerosols, which substantially enhances the SERS signal intensities by 47% compared to simple Au nanoislands. The ultrasensitive Au-TiO2 nanocomposites also demonstrate the successful detection of SARS-CoV-2 spike proteins in artificial respiratory aerosols at a 100 pM concentration level. The deep learning-based autoencoder, followed by the partial ablation of nondiscriminant SERS features of spike proteins, allows a quantitative assay of the 101-104 pfu/mL SARS-CoV-2 lysates (comparable to 19-29 PCR cyclic threshold from COVID-19 patients) in aerosols with an accuracy of over 98%. The Au-TiO2 SERS face mask provides a platform for breath biopsy for the detection of various biomarkers in respiratory aerosols.

A novel VOC breath tracer method to evaluate indoor respiratory exposures in the near- and far-fields; implications for the spread of respiratory viruses

BackgroundSeveral studies suggest that far-field transmission (>6 ft) explains a significant number of COVID-19 superspreading outbreaks.ObjectiveTherefore, quantifying the ratio of near- and far-field exposure to emissions from a source is key to better understanding human-to-human airborne infectious disease transmission and associated risks.MethodsIn this study, we used an environmentally-controlled chamber to measure volatile organic compounds (VOCs) released from a healthy participant who consumed breath mints, which contained unique tracer compounds. Tracer measurements were made at 0.76 m (2.5 ft), 1.52 m (5 ft), 2.28 m (7.5 ft) from the participant, as well as in the exhaust plenum of the chamber.ResultsWe observed that 0.76 m (2.5 ft) trials had ~36–44% higher concentrations than other distances during the first 20 minutes of experiments, highlighting the importance of the near-field exposure relative to the far-field before virus-laden respiratory aerosol plumes are continuously mixed into the far-field. However, for the conditions studied, the concentrations of human-sourced tracers after 20 minutes and approaching the end of the 60-minute trials at 0.76 m, 1.52 m, and 2.28 m were only ~18%, ~11%, and ~7.5% higher than volume-averaged concentrations, respectively.SignificanceThis study suggests that for rooms with similar airflow parameters disease transmission risk is dominated by near-field exposures for shorter event durations (e.g., initial 20–25-minutes of event) whereas far-field exposures are critical throughout the entire event and are increasingly more important for longer event durations.Impact statementWe offer a novel methodology for studying the fate and transport of airborne bioaerosols in indoor spaces using VOCs as unique proxies for bioaerosols. We provide evidence that real-time measurement of VOCs can be applied in settings with human subjects to estimate the concentration of bioaerosol at different distances from the emitter. We also improve upon the conventional assumption that a well-mixed room exhibits instantaneous and perfect mixing by addressing spatial distances and mixing over time. We quantitatively assessed the exposure levels to breath tracers at alternate distances and provided more insights into the changes on “near-field to far-field” ratios over time. This method can be used in future to estimate the benefits of alternate environmental conditions and occupant behaviors.

Design and application of a new heat-and-moisture exchanger with anti-splash sputum suctioning function

In the emergency department, open endotracheal suctioning for mechanically ventilated patients with endotracheal intubation will lead to the spread of respiratory droplets and aerosols, polluting the surrounding environment and medical staff. The traditional heat-and-moisture exchanger has the effect of warming and humidifying, and can block pathogenic microorganisms, but it does not have the function of inserting a sputum suction tube. When the heat-and-moisture exchanger is pulled out for sputum suction, it is easy to cause sputum splash, which pollutes the surrounding environment and medical personnel. The addition of closed sputum suction devices will increase the economic burden on patients. Thus, the medical staff of emergency department of the First People's Hospital of Tongxiang City of Zhejiang Province designed a new type of heat-and-moisture exchanger with anti-splash sputum suctioning function and obtained the National Utility Model Patent of China (ZL 2021 2 0017615.0). The new heat-and-moisture exchanger is mainly composed of a receiving cavity, a connecting tube, a sputum suction tube intubation tube, a sealing valve, etc. The disposable sputum suction tube can be used to insert sputum suction, and at the same time, it can prevent the secretion from splashing to ensure sealing. The patent combines the humidification and pathogen blocking functions of the heat-and-moisture exchanger with the anti-splash sputum suctioning function, which is suitable for use in the emergency and critical care medicine departments and has clinically practical value.

High Level Bioaerosol Protection against Infective Aerosols: How Medical Face Masks Compare against Respirators.

Face masks and respirators are commonly used to prevent the transmission of infectious diseases that spread by respiratory droplets and aerosols. However, there is still uncertainty about the protective effect of the different types of masks against virus containing aerosols. To determine the as-worn bioaerosol protection efficacy of different face coverings and estimate the possible protective function against airborne diseases, we challenged different respirators and medical masks on a standardized dummy head with a bioaerosol containing MS2 bacteriophages as virus surrogates. In our experiments, FFP2 respirators showed the highest filtration efficacy 94 ± 4 (SD) % followed by medical masks 93 ± 3 (SD) % and KN95 respirators 90 ± 7 (SD) %. Nevertheless, we found no statistically significant difference between respirators and medical masks in terms of provided protection against infective aerosols. Our findings indicate that both respirators and medical masks provide a high as-worn bioaerosol protection efficacy against virus containing aerosols, and therefore, a very high protection against airborne diseases. Considering the higher comfort, better availability, and lower price of medical masks in contrast to respirators, it is recommendable to use medical face masks especially in low risk situations and in general public.

A numerical approach for preventing the dispersion of infectious disease in a meeting room

Airborne transmission of respiratory aerosols carrying infectious viruses has generated many concerns about cross-contamination risks, particularly in indoor environments. ANSYS Fluent software has been used to investigate the dispersion of the viral particles generated during a coughing event and their transport dynamics inside a safe social-distance meeting room. Computational fluid dynamics based on coupled Eulerian–Lagrangian techniques are used to explore the characteristics of the airflow field in the domain. The main objective of this study is to investigate the effects of the window opening frequency, exhaust layouts, and the location of the air conditioner systems on the dispersion of the particles. The results show that reducing the output capacity by raising the concentration of suspended particles and increasing their traveled distance caused a growth in the individuals' exposure to contaminants. Moreover, decreasing the distance between the ventilation systems installed location and the ceiling can drop the fraction of the suspended particles by over 35%, and the number of individuals who are subjected to becoming infected by viral particles drops from 6 to 2. As well, the results demonstrated when the direction of input airflow and generated particles were the same, the fraction of suspended particles of 4.125%, whereas if the inputs were shifted to the opposite direction of particle injection, the fraction of particles in fluid increased by 5.000%.

#COVIDisAirborne: AI-enabled multiscale computational microscopy of delta SARS-CoV-2 in a respiratory aerosol.

We seek to completely revise current models of airborne transmission of respiratory viruses by providing never-before-seen atomic-level views of the SARS-CoV-2 virus within a respiratory aerosol. Our work dramatically extends the capabilities of multiscale computational microscopy to address the significant gaps that exist in current experimental methods, which are limited in their ability to interrogate aerosols at the atomic/molecular level and thus obscure our understanding of airborne transmission. We demonstrate how our integrated data-driven platform provides a new way of exploring the composition, structure, and dynamics of aerosols and aerosolized viruses, while driving simulation method development along several important axes. We present a series of initial scientific discoveries for the SARS-CoV-2 Delta variant, noting that the full scientific impact of this work has yet to be realized.

Aerosol measurement identifies SARS-CoV 2 PCR positive adults compared with healthy controls

BackgroundSARS-CoV-2 is spread primarily through droplets and aerosols. Exhaled aerosols are generated in the upper airways through shear stress and in the lung periphery by ‘reopening of collapsed airways’. Aerosol measuring may detect highly contagious individuals (“super spreaders or super-emitters”) and discriminate between SARS-CoV-2 infected and non-infected individuals. This is the first study comparing exhaled aerosols in SARS-CoV-2 infected individuals and healthy controls. DesignA prospective observational cohort study in 288 adults, comprising 64 patients testing positive by SARS CoV-2 PCR before enrollment, and 224 healthy adults testing negative (matched control sample) at the University Hospital Frankfurt, Germany, from February to June 2021. Study objective was to evaluate the concentration of exhaled aerosols during physiologic breathing in SARS-CoV-2 PCR-positive and -negative subjects. Secondary outcome measures included correlation of aerosol concentration to SARS-CoV-2 PCR results, change in aerosol concentration due to confounders, and correlation between clinical symptoms and aerosol. ResultsThere was a highly significant difference in respiratory aerosol concentrations between SARS-CoV-2 PCR-positive (median 1490.5/L) and -negative subjects (median 252.0/L; p < 0.0001). There were no significant differences due to age, sex, smoking status, or body mass index. ROC analysis showed an AUC of 0.8918. ConclusionsMeasurements of respiratory aerosols were significantly elevated in SARS-CoV-2 positive individuals, which helps to understand the spread and course of respiratory viral infections, as well as the detection of highly infectious individuals.

Airborne infection risk of inter-unit dispersion through semi-shaded openings: A case study of a multi-storey building with external louvers

Building design for natural ventilation and indoor air quality have become increasingly important during the past decades. Investigating airflow routes of airborne transmission and evaluating the potential infection risk in the multi-storey building is helpful to the reduction of airborne transmission. Therefore, this study applies computational fluid dynamics simulations to investigate the inter-unit dispersion pattern of gaseous pollutant between different units through semi-shaded openings. The airflow exchange and pollutant dispersion in a multi-storey building is driven by wind-induced natural ventilation. External shading louvers, which are widely used in building facades to reduce heat gain from solar radiation, are chosen to establish the semi-shaded environment. Experimental validation is performed to make sure the accuracy of numerical settings in airflow investigation of semi-shaded openings. The airflow characteristics around semi-shaded openings is analyzed in the numerical simulations. The re-entry ratio of tracer gas and the airborne infection risk of COVID-19 is investigated in the cases with different louvers’ locations and source units. The results show that the airflow is commonly slower in the semi-shaded space between louvers and openings. But the ventilation rate is not always consistent with the airflow speed because of the diversion effect from louver slats. The inter-unit infectious risk in the worst unit rises from 7.82% to 26.17% for windward shading, while it rises from 7.89% to 22.52% for leeward shading. These results are helpful to the further understanding of inter-unit transmission of infectious respiratory aerosols through external openings with complex structures.

Stability and transmissibility of SARS-CoV-2 in the environment.

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), the virus causing the ongoing global coronavirus disease 2019 (COVID‐19) pandemic, is believed to be transmitted primarily through respiratory droplets and aerosols. However, reports are increasing regarding the contamination of environmental surfaces, shared objects, and cold‐chain foods with SARS‐CoV‐2 RNA and the possibility of environmental fomite transmission of the virus raises much concern and debate. This study summarizes the current knowledge regarding potential mechanisms of environmental transmission of SARS‐CoV‐2, including the prevalence of surface contamination in various settings, the viability and stability of the virus on surfaces or fomites, as well as environmental factors affecting virus viability and survival such as temperature and relative humidity. Instances of fomite transmission, including cold‐chain food transmission, and the importance of fomite transmission in epidemics, are discussed. The knowledge gaps regarding fomite transmission of SARS‐CoV‐2 are also briefly analyzed.

Aerosolized Hydrogen Peroxide Decontamination of N95 Respirators, with Fit-Testing and Viral Inactivation, Demonstrates Feasibility for Reuse during the COVID-19 Pandemic.

ABSTRACTIn response to the demand for N95 respirators by health care workers during the COVID-19 pandemic, we evaluated decontamination of N95 respirators using an aerosolized hydrogen peroxide (aHP) system. This system is designed to dispense a consistent atomized spray of aerosolized, 7% hydrogen peroxide (H2O2) solution over a treatment cycle. Multiple N95 respirator models were subjected to 10 or more cycles of respirator decontamination, with a select number periodically assessed for qualitative and quantitative fit testing. In parallel, we assessed the ability of aHP treatment to inactivate multiple viruses absorbed onto respirators, including phi6 bacteriophage, herpes simplex virus 1 (HSV-1), coxsackievirus B3 (CVB3), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). For pathogens transmitted via respiratory droplets and aerosols, it is critical to address respirator safety for reuse. This study provided experimental validation of an aHP treatment process that decontaminates the respirators while maintaining N95 function. External National Institute for Occupational Safety & Health (NIOSH) certification verified respirator structural integrity and filtration efficiency after 10 rounds of aHP treatment. Virus inactivation by aHP was comparable to the decontamination of commercial spore-based biological indicators. These data demonstrate that the aHP process is effective, with successful fit-testing of respirators after multiple aHP cycles, effective decontamination of multiple virus species, including SARS-CoV-2, successful decontamination of bacterial spores, and filtration efficiency maintained at or greater than 95%. While this study did not include extended or clinical use of N95 respirators between aHP cycles, these data provide proof of concept for aHP decontamination of N95 respirators before reuse in a crisis-capacity scenario.IMPORTANCE The COVID-19 pandemic led to unprecedented pressure on health care and research facilities to provide personal protective equipment. The respiratory nature of the SARS-CoV2 pathogen makes respirator facepieces a critical protective measure to limit inhalation of this virus. While respirator facepieces were designed for single use and disposal, the pandemic increased overall demand for N95 respirators, and corresponding manufacturing and supply chain limitations necessitated the safe reuse of respirators when necessary. In this study, we repurposed an aerosolized hydrogen peroxide (aHP) system that is regularly utilized to decontaminate materials in a biosafety level 3 (BSL3) facility, to develop a method for decontamination of N95 respirators. Results from viral inactivation, biological indicators, respirator fit testing, and filtration efficiency testing all indicated that the process was effective at rendering N95 respirators safe for reuse. This proof-of-concept study establishes baseline data for future testing of aHP in crisis-capacity respirator-reuse scenarios.

COVID-19 Pandemisinde Sağlık Çalışanı Olarak Hemşirelerin Karşılaştığı Sorunlar

Şiddetli akut solunum sendromu koronavirüs-2 (SARS-CoV-2), solunum damlacıkları, temas ve aerosoller yoluyla bulaşabilen ve dünya çapında büyük ölçekli enfeksiyonlara neden olan pandemiye yol açmıştır. Salgınla en ön safta mücadele eden hemşireler, fiziksel ve psikolojik sıkıntılar yaşamaktadır. Bu psikolojik sıkıntılar, ağırlıklı olarak uyku bozukluğu, anksiyete ve depresyon belirtileri, travma sonrası stres, karar verememe ve hatta somatik belirtiler olabilmektedir. Bu derlemede COVID-19 pandemisinden en çok etkilenen sağlık profesyonelleri arasında yer alan hemşirelerin sorunlarına değinilmiştir. Sağlık çalışanlarının, etki düzeyinin psikolojik ve duygusal toleransı aştığı, travma düzeyinin yüksek olduğu bilinmektedir. Uzun iş vardiyaları (günde ortalama 16 saate ulaşan), oldukça bulaşıcı bir hastalığa yakalanma riskinin yüksek olması ve yeterli koruma önlemlerinin alınmaması karşısında, sağlık çalışanları arasında psikolojik sıkıntılar ortaya çıkmaktadır. Pandemi, etik sorunlarının yanı sıra psikolojik ve ruhsal sorunları da beraberinde getirmektedir. Covid-19 pandemisi ile hemşirelik mesleği ve hemşirelik bakımı ulusal ve uluslararası platformlarda yeniden gündem olup, önemli hale gelmiştir. Yapılan çalışmalar incelendiğinde covid 19’un hemşirelere yansıyan yüzünün en fazla psikolojik olduğu görülmektedir. Hemşirelere pandemi gibi yoğun çalışılan dönemlerde psikolojik destek sağlanması önem arz etmektedir.

Review Onepidemiology of Contagious Bovine Pleuoro Pneumonia and Its Economic Impacts in Ethiopia

Mycoplasma Mycoides subsp. Mycoides “Small Colony” (MmmSC) causes the infectious and contagious respiratory disease known as Contagious Bovine Pleuropneumonia (CBPP), which has a significant negative effect on livestock output and the propensity to spread quickly. The aim of this paper is to review the epidemiology and economic impacts of CBPP in Ethiopia. Contagious Bovine pleuropneumonia is an endemic disease in Africa, Asia, Eastern Europe, and the Iberian Peninsula. Contagious Bovine pleuropneumonia is mainly transmitted from animal to animal in respiratory aerosols. The clinical manifestations of CBPP in cattle range from hyper acute, acute, sub acute and chronic forms. Diagnosis CBPP based on a history of contact with infected animals, clinical findings, Immuno-diagnosis tests, necropsy findings and cultural examination. Thrombosis in the pulmonary arteries is a hallmark of the CBPP pathogenesis in susceptible animals. The impact that Contagious Bovine Pleuropneumonia (CBPP) can impart in an economy of a given country is so vast and tremendous that it is not advisable to overlook like any of the ordinary routine diseases of livestock that can be easily removed by treatment or self-cure. Movement control, vaccination, and treatment are essential tools in CBPP control and eradication. Regular program of mass vaccination and best treatment regime. Moreover, effective vaccination policy needs to be considered as it is the only realistic method of choice for control of CBPP in Ethiopia.

A Novel Antipathogenic Agent for Nonwoven Fabric

Medical-grade masks and N95 respirators containing non-woven fibers are designed to prevent the spread of airborne diseases. While they effectively trap respiratory droplets and aerosols, they cannot lyse entrapped pathogens. Embedded antimicrobial agents such as silver, copper, zinc, iodine, peptides, quaternary ammonium salts, or nanoparticles have been used to overcome this limitation. However, their effectiveness remains debatable because these materials can be toxins, allergens, irritants, and environmental hazards. Recently, silicon nitride (Si3N4) was found to be a potent antipathogenic compound, and it may be an ideal agent for masks. In powder or solid form, it is highly effective in inactivating bacteria, fungi, and viruses while leaving mammalian tissue unaffected. The purpose of this study was to serially assess the antiviral efficacy of Si3N4 against SARS-CoV-2 using powders, solids, and embedded nonwoven fabrics. Si3N4 powders and solids were prepared using conventional ceramic processing. The “pad-dry-cure” method was used to embed Si3N4 particles into polypropylene fibers. Fabric testing was subsequently conducted using industrial standards—ISO 18184 for antiviral effectiveness, ASTM F2299 and EN 13274-7 for filtration efficiency, EN 14683 for differential pressure drop, and ISO 18562-2 for particle shedding. A modification of ISO 18562-3 was also employed to detect ammonia release from the fabric. Antiviral effectiveness for Si3N4 powders, solids, and embedded fabrics were 99.99% at ≤ 5 min, ~ 93% in 24 h, and 87% to 92% in 120 min, respectively. Results of the standard mask tests were generally within prescribed safety limits. Further process optimization may lead to commercial Si3N4-based masks that not only “catch” but also “kill” pathogenic microbes.

Nanomechanics and Morphology of Simulated Respiratory Particles

The impact of respiratory particle composition on the equilibrium morphology and phase is not well understood. Furthermore, the effects of these different phases and morphologies on the viability of viruses embedded within these particles are equally unknown. Physiologically relevant respiratory fluid analogues were constructed, and their hygroscopic behavior was measured using an ensemble technique. A relationship between hygroscopicity and protein concentration was determined, providing additional validation to the high protein content of respiratory aerosol measured in prior works (>90%). It was found that the salt component of the respiratory particles could crystallize as a single crystal, multiple crystals, or would not crystallize at all. It was found that dried protein particles at indoor-relevant climatic conditions could exist separately in a glassy (∼77% of particles) or viscoelastic state (∼23% of particles). The phase state and morphology of respiratory particles may influence the viability of embedded pathogens. We recommend that pathogen research aiming to mimic the native composition of respiratory fluid should use a protein concentration of at least 90% by solute volume to improve the representativity of the pathogen's microenvironment.

Abigail Dommer

Maybe you saw the video on the New York Times website—a rippling sphere with ragged posts sticking out on thin stalks. It was an atomic-level model of SARS-CoV-2, the virus that causes COVID-19. Abigail Dommer was one of the University of California San Diego scientists who created that model. A PhD student at the time, she and her team modeled the coronavirus inside a respiratory aerosol , a supercomputing tour de force that calculated the interactions of over 1 billion individual atoms. The SARS-CoV-2 model has been just one of the enormous molecular puzzles Dommer has solved computationally. These projects could help scientists understand how viruses move from person to person through the air or how sea spray induces clouds to form. Dommer’s path to supercomputing superstar hasn’t been linear. She started her PhD in Kimberly Prather’s atmospheric chemistry and oceanography lab at UC San Diego before leaving graduate school

Intranasal SARS-CoV-2 Vaccines: Indispensable and Inevitable

Their extraordinary efficacy notwithstanding, the parenterally administered mRNA vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have proven incapable of preventing breakthrough infections in otherwise fully vaccinated subjects.1 Interpersonal transmission of SARS-CoV-2 through respiratory droplets and aerosols by fully vaccinated subjects has also proven resistant to vaccine-induced immunity.1 These relative shortcomings of the parenterally administered mRNA vaccines are hardly unanticipated because upper airway protection against SARS-CoV-2 replication and shedding requires local mucosal rather than systemic humoral immunity.

Impact of Chemical Properties of Human Respiratory Droplets and Aerosol Particles on Airborne Viruses' Viability and Indoor Transmission.

The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been identified as a potential pandemic challenge, especially in poorly ventilated indoor environments, such as certain hospitals, schools, public buildings, and transports. The impacts of meteorological parameters (temperature and humidity) and physical property (droplet size) on the airborne transmission of coronavirus in indoor settings have been previously investigated. However, the impacts of chemical properties of viral droplets and aerosol particles (i.e., chemical composition and acidity (pH)) on viability and indoor transmission of coronavirus remain largely unknown. Recent studies suggest high organic content (proteins) in viral droplets and aerosol particles supports prolonged survival of the virus by forming a glassy gel-type structure that restricts the virus inactivation process under low relative humidity (RH). In addition, the virus survival was found at neutral pH, and inactivation was observed to be best at low (<5) and high pH (>10) values (enveloped bacteriophage Phi6). Due to limited available information, this article illustrates an urgent need to research the impact of chemical properties of exhaled viral particles on virus viability. This will improve our fundamental understanding of indoor viral airborne transmission mechanisms.

Hybrid measurement of respiratory aerosol reveals a dominant coarse fraction resulting from speech that remains airborne for minutes

Accurate measurements of the size and quantity of aerosols generated by various human activities in different environments are required for efficacious mitigation strategies and accurate modeling of respiratory disease transmission. Previous studies of speech droplets, using standard aerosol instrumentation, reported very few particles larger than 5 μm. This starkly contrasts with the abundance of such particles seen in both historical slide deposition measurements and more recent light scattering observations. We have reconciled this discrepancy by developing an alternative experimental approach that addresses complications arising from nucleated condensation. Measurements reveal that a large volume fraction of speech-generated aerosol has diameters in the 5- to 20-μm range, making them sufficiently small to remain airborne for minutes, not hours. This coarse aerosol is too large to penetrate the lower respiratory tract directly, and its relevance to disease transmission is consistent with the vast majority of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections initiating in the upper respiratory tract. Our measurements suggest that in the absence of symptoms such as coughing or sneezing, the importance of speech-generated aerosol in the transmission of respiratory diseases is far greater than generally recognized.

Aerosol Transport Modeling: The Key Link Between Lung Infections of Individuals and Populations.

The recent COVID-19 pandemic has propelled the field of aerosol science to the forefront, particularly the central role of virus-laden respiratory droplets and aerosols. The pandemic has also highlighted the critical need, and value for, an information bridge between epidemiological models (that inform policymakers to develop public health responses) and within-host models (that inform the public and health care providers how individuals develop respiratory infections). Here, we review existing data and models of generation of respiratory droplets and aerosols, their exhalation and inhalation, and the fate of infectious droplet transport and deposition throughout the respiratory tract. We then articulate how aerosol transport modeling can serve as a bridge between and guide calibration of within-host and epidemiological models, forming a comprehensive tool to formulate and test hypotheses about respiratory tract exposure and infection within and between individuals.

Factors associated with sexual intercourse among Brazilian men during the COVID-19 pandemic: a cross-sectional study

Introduction: Transmission of COVID-19 occurs from person to person through respiratory droplets and aerosol, through contact and direct transmission, through kissing, handshaking, etc. In this perspective, several countries have implemented actions and strategies to reduce the risks of transmission. Because of this, there are several widespread reflexes and concerns resulting from the COVID-19 pandemic. One change in behavior that can be affected due to the social distance that occurred during the COVID-19 pandemic is sexual activity. Objective: To analyze the factors associated with the sexual intercourse of Brazilian men during the COVID-19 pandemic. Methods: 518 men over 18 years of age responded to the online survey that included sociodemographic, clinical, behavioral, and anthropometric characteristics and the International Index of Erectile Function (IIEF). The sample was divided into two groups according to the practice of sexual intercourse during the COVID-19 pandemic. Results: Through multivariate regression analysis, being satisfied or equally dissatisfied/satisfied with sex life and being in a stable relationship were the factors associated with the sexual intercourse of Brazilian men during the COVID-19 pandemic. In addition, not drinking alcohol was a protective factor for sexual intercourse in this sample. Conclusion: In our study, being satisfied or equally dissatisfied/satisfied with the overall sex life and having a stable relationship were associated with intercourse during a COVID-19 pandemic. On the other hand, not drinking alcohol was considered a protective factor.