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A special issue of International Journal of Environmental Research and Public Health (ISSN 1660-4601). This special issue belongs to the section "Global Health".

Deadline for manuscript submissions: closed (31 December 2020) | Viewed by 124506

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Dr. Alessandro Miani

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Department of Environmental Science and Policy (ESP), University of Milano, Via Celoria, 2-20133 Milan, Italy
Interests: environmental medicine;epidemiology; preventive medicine; indoor pollution; asbestos-related diseases; radon;
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Dear Colleagues,

It is noteworthy that environmental pollution may affect several human organs and systems. Some evidence have been published about the survival in the aerosol of Sars-CoV-2, the virus causing the COVID-19 outbreak. It has also been hypothesized that exposure to fine particulate concentrations can in some way influence the progression of the epidemics, possibly due to underlying weakness of the immune system in people (especially in the elderly) constantly exposed to high levels of PM10, PM2.5, PM1 and ultrafine particulate. By looking at the fast and dramatic outbreak observed in Northern Italy with very high mortality rates, the Italian Society of Environmental Medicine (SIMA) has been the first scientific society to publish a position paper questioning if particulate matter can be considered as an indicator of COVID-19 diffusion and, most importantly, of its health outcomes. More recently, a study from Harvard University has directly related the increase of PM 2.5 particulate to mortality rates due to COVID-19.

By proposing this special issue, we are underlying the need for further scientific evaluations and studies concerning the association between air pollution and COVID-19, with the aim of contributing to produce evidence on this topic. Observational studies as well as position papers, and articles addressing the patho- physiological mechanism underlying the association between air pollution and health outcomes of COVID-19 epidemics are welcome. Epidemiological surveys, systematic reviews, meta-analyses, original research articles (even from biologists and molecular biologists or biochemicals), short articles or commentaries are solicited and expected to add relevant information to the current knowledge.

Dr. Alessandro Miani
Guest Editor

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Keywords

Air Pollution
Fine Particulate
Covid-19
Environment
Outbreak
Epidemics

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Published Papers (9 papers)

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Editorial

Jump to: Research

5 pages, 289 KiB

Open AccessEditorial

Searching for SARS-COV-2 on Particulate Matter: A Possible Early Indicator of COVID-19 Epidemic Recurrence

by Leonardo Setti, Fabrizio Passarini, Gianluigi De Gennaro, Pierluigi Barbieri, Alberto Pallavicini, Maurizio Ruscio, Prisco Piscitelli, Annamaria Colao and Alessandro Miani

Int. J. Environ. Res. Public Health 2020, 17(9), 2986; https://doi.org/10.3390/ijerph17092986 - 25 Apr 2020

Cited by 136 | Viewed by 13762

Abstract

A number of nations were forced to declare a total shutdown due to COVID-19 infection, as extreme measure to cope with dramatic impact of the pandemic, with remarkable consequences both in terms of negative health outcomes and economic loses. However, in many countries a “Phase-2” is approaching and many activities will re-open soon, although with some differences depending on the severity of the outbreak experienced and SARS-COV-2 estimated diffusion in the general population. At the present, possible relapses of the epidemic cannot be excluded until effective vaccines or immunoprophylaxis with human recombinant antibodies will be properly set up and commercialized. COVD-19-related quarantines have triggered serious social challenges, so that decision makers are concerned about the risk of wasting all the sacrifices imposed to the people in these months of quarantine. The availability of possible early predictive indicators of future epidemic relapses would be very useful for public health purposes, and could potentially prevent the suspension of entire national economic systems. On 16 March, a Position Paper launched by the Italian Society of Environmental Medicine (SIMA) hypothesized for the first time a possible link between the dramatic impact of COVID-19 outbreak in Northern Italy and the high concentrations of particulate matter (PM₁₀ and PM_2.5) that characterize this area, along with its well-known specific climatic conditions. Thereafter, a survey carried out in the U.S. by the Harvard School of Public Health suggested a strong association between increases in particulate matter concentration and mortality rates due to COVID-19. The presence of SARS-COV-2 RNA on the particulate matter of Bergamo, which is not far from Milan and represents the epicenter of the Italian epidemic, seems to confirm (at least in case of atmospheric stability and high PM concentrations, as it usually occurs in Northern Italy) that the virus can create clusters with the particles and be carried and detected on PM₁₀. Although no assumptions can be made concerning the link between this first experimental finding and COVID-19 outbreak progression or severity, the presence of SARS-COV-2 RNA on PM₁₀ of outdoor air samples in any city of the world could represent a potential early indicator of COVID-19 diffusion. Searching for the viral genome on particulate matter could therefore be explored among the possible strategies for adopting all the necessary preventive measures before future epidemics start. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

6 pages, 284 KiB

Open AccessEditorial

Airborne Transmission Route of COVID-19: Why 2 Meters/6 Feet of Inter-Personal Distance Could Not Be Enough

by Leonardo Setti, Fabrizio Passarini, Gianluigi De Gennaro, Pierluigi Barbieri, Maria Grazia Perrone, Massimo Borelli, Jolanda Palmisani, Alessia Di Gilio, Prisco Piscitelli and Alessandro Miani

Int. J. Environ. Res. Public Health 2020, 17(8), 2932; https://doi.org/10.3390/ijerph17082932 - 23 Apr 2020

Cited by 437 | Viewed by 48957

Abstract

The COVID-19 pandemic caused the shutdown of entire nations all over the world. In addition to mobility restrictions of people, the World Health Organization and the Governments have prescribed maintaining an inter-personal distance of 1.5 or 2 m (about 6 feet) from each other in order to minimize the risk of contagion through the droplets that we usually disseminate around us from nose and mouth. However, recently published studies support the hypothesis of virus transmission over a distance of 2 m from an infected person. Researchers have proved the higher aerosol and surface stability of SARS-COV-2 as compared with SARS-COV-1 (with the virus remaining viable and infectious in aerosol for hours) and that airborne transmission of SARS-CoV can occur besides close-distance contacts. Indeed, there is reasonable evidence about the possibility of SARS-COV-2 airborne transmission due to its persistence into aerosol droplets in a viable and infectious form. Based on the available knowledge and epidemiological observations, it is plausible that small particles containing the virus may diffuse in indoor environments covering distances up to 10 m from the emission sources, thus representing a kind of aerosol transmission. On-field studies carried out inside Wuhan Hospitals showed the presence of SARS-COV-2 RNA in air samples collected in the hospitals and also in the surroundings, leading to the conclusion that the airborne route has to be considered an important pathway for viral diffusion. Similar findings are reported in analyses concerning air samples collected at the Nebraska University Hospital. On March 16th, we have released a Position Paper emphasizing the airborne route as a possible additional factor for interpreting the anomalous COVID-19 outbreaks in northern Italy, ranked as one of the most polluted areas in Europe and characterized by high particulate matter (PM) concentrations. The available information on the SARS-COV-2 spreading supports the hypothesis of airborne diffusion of infected droplets from person to person at a distance greater than two meters (6 feet). The inter-personal distance of 2 m can be reasonably considered as an effective protection only if everybody wears face masks in daily life activities. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

Research

Jump to: Editorial

16 pages, 2583 KiB

Open AccessArticle

Geographical Pattern of COVID-19-Related Outcomes over the Pandemic Period in France: A Nationwide Socio-Environmental Study

by Séverine Deguen and Wahida Kihal-Talantikite

Int. J. Environ. Res. Public Health 2021, 18(4), 1824; https://doi.org/10.3390/ijerph18041824 - 13 Feb 2021

Cited by 17 | Viewed by 3209

Abstract

Background: Several studies have investigated the implication of air pollution and some social determinants on COVID-19-related outcomes, but none of them assessed the implication of spatial repartition of the socio-environmental determinants on geographic variations of COVID-19 related outcomes. Understanding spatial heterogeneity in relation to the socio-environmental determinant and COVID-19-related outcomes is central to target interventions toward a vulnerable population. Objectives: To determine the spatial variability of COVID-19 related outcomes among the elderly in France at the department level. We also aimed to assess whether a geographic pattern of Covid-19 may be partially explained by spatial distribution of both long-term exposure to air pollution and deprived living conditions. Methods: This study considered four health events related to COVID-19 infection over the period of 18 March and 02 December 2020: (i) hospitalization, (ii) cases in intensive health care in the hospital, (iii) death in the hospital, and (iv) hospitalized patients recovered and returned back home. We used the percentage of household living in an overcrowding housing to characterize the living conditions and long-term exposure to NO₂ to analyse the implication of air pollution. Using a spatial scan statistic approach, a Poisson cluster analysis method based on a likelihood ratio test and Monte Carlo replications was applied to identify high-risk clusters of a COVID-19-related outcome. Result: our results revealed that all the outcomes related to COVID-19 infection investigated were not randomly distributed in France with a statistically significant cluster of high risk located in Eastern France of the hospitalization, cases in the intensive health care at the hospital, death in the hospital, and recovered and returned back home compared to the rest of France (relative risk, RR = 1.28, p-value = 0.001, RR = 3.05, p = 0.001, RR = 2.94, p = 0.001, RR = 2.51, p = 0.001, respectively). After adjustments for socio-environmental determinants, the crude cluster shifts according to different scenarios suggested that both the overcrowding housing level and long-term exposure to largely NO₂ explain the spatial distribution of COVID-19-related outcomes. Conclusions: Our findings suggest that the geographic pattern of COVID-19-related outcomes is largely explained by socio-spatial distribution of long-term exposure to NO₂. However, to better understand spatial variations of COVID-19-related outcomes, it would be necessary to investigate and adjust it for other determinants. Thus, the current sanitary crisis reminds us of how unequal we all are in facing this disease. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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11 pages, 1661 KiB

Open AccessArticle

The Effects of Air Pollution, Sea Exposure and Altitude on COVID-19 Hospitalization Rates in Italy

by Ennio Cascetta, Ilaria Henke and Luigi Di Francesco

Int. J. Environ. Res. Public Health 2021, 18(2), 452; https://doi.org/10.3390/ijerph18020452 - 8 Jan 2021

Cited by 28 | Viewed by 4191

Abstract

Early known cases of COVID-19 emerged in late 2019 in the city of Wuhan (China) and in a relatively short time, it has reached more than 200 countries up to July 2020. In Italy, from 21 February 2020, (first official Italian positive case of COVID-19) until 27 July 2020, 246,286 confirmed cases were observed of which over 68,150 (28%) needed hospitalization and 35,112 died. In recent scientific research, it has been shown that the severity of symptoms and mortality rates were different not only among the various countries of the world but also in different regions of the same country. This research investigates whether and by how much air environmental conditions (such as exposure to fine particulate matter-PM_2.5, sea air masses and altitude) influences the risk of hospitalization due to COVID-19 in Italy, once the spreading of the virus and the percentage of the elderly in the population have been accounted for. A log-linear multiple regression model was estimated where the log of the ratio of hospitalized patients per inhabitant, since the beginning of the epidemic up to July 27, has been considered as a dependent variable. Among the independent variables, the ones that have been taken into account are the spreading of the virus, the rate of people over 50 years of age, the concentration of PM_2.5, the rate of population living by the sea, the rate of green public space for each resident and the ratio of population living at a high altitude. The results showed an increase in the hospitalization rate in terms of the percentage of people over 50 and the average concentration of PM_2.5. If average limits of PM_2.5 concentration allowed by the current European regulations (25 µg/m³) were respected in all Italian provinces, that would have led to 7339 less hospitalizations for COVID-19 (−11%). On the contrary, near the coast there were lower hospitalized cases in the referred period. In the hypothetical case that no Italians lived near the sea, about 1363 (+2%) more hospitalizations would have been recorded in the analysis period in addition to the effect of a lower PM concentration. This paper wanted to investigate which are the areas with a higher risk of hospitalization in Italy, so as to help the Italian Government to strengthen Health System measures, predicting the most suffering areas and health care systems. According to the results, this is directly related to the severity of symptoms which decreased with the long-time exposure to the sea. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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33 pages, 7550 KiB

Open AccessArticle

Bad Air Can Also Kill: Residential Indoor Air Quality and Pollutant Exposure Risk during the COVID-19 Crisis

by Samuel Domínguez-Amarillo, Jesica Fernández-Agüera, Sonia Cesteros-García and Roberto Alonso González-Lezcano

Int. J. Environ. Res. Public Health 2020, 17(19), 7183; https://doi.org/10.3390/ijerph17197183 - 30 Sep 2020

Cited by 96 | Viewed by 20327

Abstract

During the first outbreak of the SARS-CoV-2 pandemic the population, focusing primarily on the risk of infection, was generally inattentive to the quality of indoor air. Spain, and the city of Madrid in particular, were among the world’s coronavirus hotspots. The country’s entire population was subject to a 24/7 lockdown for 45 days. This paper describes a comparative longitudinal survey of air quality in four types of housing in the city of Madrid before and during lockdown. The paper analysed indoor temperatures and variations in CO₂, 2.5 μm particulate matter (PM_2.5) and total volatile organic compound (TVOC) concentrations before and during lockdown. The mean daily outdoor PM_2.5 concentration declined from 11.04 µg/m³ before to 7.10 µg/m³ during lockdown. Before lockdown the NO₂ concentration values scored as ‘very good’ 46% of the time, compared to 90.9% during that period. Although the city’s outdoor air quality improved, during lockdown the population’s exposure to indoor pollutants was generally more acute and prolonged. Due primarily to concern over domestic energy savings, the lack of suitable ventilation and more intensive use of cleaning products and disinfectants during the covid-19 crisis, indoor pollutant levels were typically higher than compatible with healthy environments. Mean daily PM_2.5 concentration rose by approximately 12% and mean TVOC concentration by 37% to 559%. The paper also puts forward a series of recommendations to improve indoor domestic environments in future pandemics and spells out urgent action to be taken around indoor air quality (IAQ) in the event of total or partial quarantining to protect residents from respiratory ailments and concomitantly enhanced susceptibility to SARS-CoV-2, as identified by international medical research. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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16 pages, 3836 KiB

Open AccessArticle

Reusable Face Masks as Alternative for Disposable Medical Masks: Factors that Affect their Wear-Comfort

by Ka-Po Lee, Joanne Yip, Chi-Wai Kan, Jia-Chi Chiou and Ka-Fu Yung

Int. J. Environ. Res. Public Health 2020, 17(18), 6623; https://doi.org/10.3390/ijerph17186623 - 11 Sep 2020

Cited by 56 | Viewed by 13528

Abstract

The coronavirus outbreak that commenced at the end of 2019 has led to a dramatic increase in the demand for face masks. In countries that are experiencing a shortage of face masks as a result of panic buying or inadequate supply, reusable fabric masks have become a popular option, because they are often considered more cost-effective and environmentally friendly than disposable medical masks. Nevertheless, there remains a significant variation in the quality and performance of existing face masks; not all are simultaneously able to provide protection against the extremely contagious virus and be comfortable to wear. This study aims to examine the influential factors that affect the comfort of reusable face masks, but not to assess the antimicrobial or antiviral potential. Seven types of masks were selected in this study and subjected to air and water vapor permeability testing, thermal conductivity testing and a wear trial. The results indicate that washable face masks made of thin layers of knitted fabric with low density and a permeable filter are more breathable. Additionally, masks that contain sufficient highly thermally conductive materials and have good water vapor permeability are often more comfortable to wear as they can transfer heat and moisture from the body quickly, and thus do not easily dampen and deteriorate. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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17 pages, 5320 KiB

Open AccessArticle

Impact of HVAC-Systems on the Dispersion of Infectious Aerosols in a Cardiac Intensive Care Unit

by Larisa Anghel, Cătălin-George Popovici, Cristian Stătescu, Radu Sascău, Marina Verdeș, Vasilică Ciocan, Ionela-Lăcrămioara Șerban, Minela Aida Mărănducă, Sebastian-Valeriu Hudișteanu and Florin-Emilian Țurcanu

Int. J. Environ. Res. Public Health 2020, 17(18), 6582; https://doi.org/10.3390/ijerph17186582 - 10 Sep 2020

Cited by 31 | Viewed by 5447

Abstract

At the end of 2019, a variation of a coronavirus, named SARS-CoV-2, has been identified as being responsible for a respiratory illness disease (COVID-19). Since ventilation is an important factor that influences airborne transmission, we proposed to study the impact of heating, ventilation and air-conditioning (HVAC) with a variable air volume (VAV) primary air system, on the dispersion of infectious aerosols, in a cardiac intensive care unit, using a transient simulation with computational fluid dynamics (CFD), based on the finite element method (FEM). We analyzed three scenarios that followed the dispersion of pathogen carrying expiratory droplets particles from coughing, from patients possibly infected with COVID-19, depending on the location of the patients in the intensive care unit. Our study provides the mechanism for spread of infectious aerosols, and possibly of COVID-19 infection, by air conditioning systems and also highlights important recommendations for disease control and optimization of ventilation in intensive care units, by increasing the use of outdoor air and the rate of air change, decreasing the recirculation of air and using high-efficiency particulate air (HEPA) filters. The CFD-FEM simulation approach that was applied in our study could also be extended to other targets, such as public transport, theaters, philharmonics and amphitheaters from educational units. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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26 pages, 2475 KiB

Open AccessArticle

Forecasting Covid-19 Dynamics in Brazil: A Data Driven Approach

by Igor Gadelha Pereira, Joris Michel Guerin, Andouglas Gonçalves Silva Júnior, Gabriel Santos Garcia, Prisco Piscitelli, Alessandro Miani, Cosimo Distante and Luiz Marcos Garcia Gonçalves

Int. J. Environ. Res. Public Health 2020, 17(14), 5115; https://doi.org/10.3390/ijerph17145115 - 15 Jul 2020

Cited by 42 | Viewed by 5401

Abstract

The contribution of this paper is twofold. First, a new data driven approach for predicting the Covid-19 pandemic dynamics is introduced. The second contribution consists in reporting and discussing the results that were obtained with this approach for the Brazilian states, with predictions starting as of 4 May 2020. As a preliminary study, we first used an Long Short Term Memory for Data Training-SAE (LSTM-SAE) network model. Although this first approach led to somewhat disappointing results, it served as a good baseline for testing other ANN types. Subsequently, in order to identify relevant countries and regions to be used for training ANN models, we conduct a clustering of the world’s regions where the pandemic is at an advanced stage. This clustering is based on manually engineered features representing a country’s response to the early spread of the pandemic, and the different clusters obtained are used to select the relevant countries for training the models. The final models retained are Modified Auto-Encoder networks, that are trained on these clusters and learn to predict future data for Brazilian states. These predictions are used to estimate important statistics about the disease, such as peaks and number of confirmed cases. Finally, curve fitting is carried out to find the distribution that best fits the outputs of the MAE, and to refine the estimates of the peaks of the pandemic. Predicted numbers reach a total of more than one million infected Brazilians, distributed among the different states, with São Paulo leading with about 150 thousand confirmed cases predicted. The results indicate that the pandemic is still growing in Brazil, with most states peaks of infection estimated in the second half of May 2020. The estimated end of the pandemics (97% of cases reaching an outcome) spread between June and the end of August 2020, depending on the states. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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9 pages, 2851 KiB

Open AccessArticle

Covid-19 Outbreak Progression in Italian Regions: Approaching the Peak by the End of March in Northern Italy and First Week of April in Southern Italy

by Cosimo Distante, Prisco Piscitelli and Alessandro Miani

Int. J. Environ. Res. Public Health 2020, 17(9), 3025; https://doi.org/10.3390/ijerph17093025 - 27 Apr 2020

Cited by 77 | Viewed by 7697

Abstract

Epidemiological figures of the SARS-CoV-2 epidemic in Italy are higher than those observed in China. Our objective was to model the SARS-CoV-2 outbreak progression in Italian regions vs. Lombardy to assess the epidemic’s progression. Our setting was Italy, and especially Lombardy, which is experiencing a heavy burden of SARS-CoV-2 infections. The peak of new daily cases of the epidemic has been reached on the 29th, while was delayed in Central and Southern Italian regions compared to Northern ones. In our models, we estimated the basic reproduction number (R₀), which represents the average number of people that can be infected by a person who has already acquired the infection, both by fitting the exponential growth rate of the infection across a 1-month period and also by using day-by-day assessments based on single observations. We used the susceptible–exposed–infected–removed (SEIR) compartment model to predict the spreading of the pandemic in Italy. The two methods provide an agreement of values, although the first method based on exponential fit should provide a better estimation, being computed on the entire time series. Taking into account the growth rate of the infection across a 1-month period, each infected person in Lombardy has involved 4 other people (3.6 based on data of April 23rd) compared to a value of

R_{0} = 2.68

, as reported in the Chinese city of Wuhan. According to our model, Piedmont, Veneto, Emilia Romagna, Tuscany and Marche will reach an R₀ value of up to 3.5. The R₀ was 3.11 for Lazio and 3.14 for the Campania region, where the latter showed the highest value among the Southern Italian regions, followed by Apulia (3.11), Sicily (2.99), Abruzzo (3.0), Calabria (2.84), Basilicata (2.66), and Molise (2.6). The R₀ value is decreased in Lombardy and the Northern regions, while it is increased in Central and Southern regions. The expected peak of the SEIR model is set at the end of March, at a national level, with Southern Italian regions reaching the peak in the first days of April. Regarding the strengths and limitations of this study, our model is based on assumptions that might not exactly correspond to the evolution of the epidemic. What we know about the SARS-CoV-2 epidemic is based on Chinese data that seems to be different than those from Italy; Lombardy is experiencing an evolution of the epidemic that seems unique inside Italy and Europe, probably due to demographic and environmental factors. Full article

(This article belongs to the Special Issue Air Pollution & COVID-19 Outbreak)

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