Exposure to particulate matter: direct and indirect role in the COVID-19 pandemic

Knowing the transmission factors and the natural environment that favor the spread of a viral infection is crucial to stop outbreaks and develop effective preventive strategies. This work aims to evaluate the role of Particulate Matter (PM) in the COVID-19 pandemic, focusing especially on that of PM as a vector for SARS-CoV-2. Exposure to PM has been related to new cases and to the clinical severity of people infected by SARS-CoV-2, which can be explained by the oxidative stress and the inflammatory response generated by these particles when entering the respiratory system, as well as by the role of PM in the expression of ACE-2 in respiratory cells in human hosts. In addition, different authors have detected SARS-CoV-2 RNA in PM sampled both in outdoor and indoor environments. The results of various studies lead to the hypothesis that the aerosols emitted by an infected person could be deposited in other suspended particles, sometimes of natural but especially of anthropogenic origin, that form the basal PM. However, the viability of the virus in PM has not yet been demonstrated. Should PM be confirmed as a vector of transmission, prevention strategies ought to be adapted, and PM sampling in outdoor environments could become an indicator of viral load in a specific area.“This work has been carried out within the framework of the project “Air pollution and COVID-19: what can we learn from this pandemic?” of the Call for Grants from the BBVA Foundation to Scientific Research Teams in SARS-CoV-2 and COVID-19, in the area of Ecology and Veterinary Medicine

Air pollution and COVID-19: direct and indirect effects

RESUMEN : La nueva neumonía por coronavirus, COVID-19, se ha convertido en un problema de salud pública mundial. Desde los primeros meses de la pandemia se están investigando todos los aspectos que pueden estar relacionados con la enfermedad, desde sus causas hasta su tratamiento, pasando por el estudio de los factores de riesgo que pueden agravar su incidencia y letalidad. Además de la dinámica de transmisión de persona a persona del nuevo virus respiratorio, se ha estudiado el papel de los factores ambientales en la aceleración de la propagación del SARS-CoV-2 y su letalidad. Actualmente, la contaminación atmosférica es la principal causa ambiental de enfermedad y muerte prematura en el mundo. El presente trabajo pretende analizar la hipótesis de que la contaminación del aire (especialmente PM2,5 y PM10), resultante de una combinación de factores como los datos meteorológicos, el nivel de industrialización y la topografía regional, puede actuar como portador de la infección y como factor de agravamiento del impacto en la salud de la enfermedad COVID-19. En los resultados se encuentra que durante las distintas fases del estado de alarma ha disminuido la concentración de los principales contaminantes atmosféricos. Por su parte, la contaminación parece relacionarse con la gravedad en el cuadro clínico de los pacientes con Covid-19. Para acabar, si bien la mayor parte de trabajos destacan que el material particulado puede actuar como vector del SARS-CoV-2, aún no se conoce la viabilidad del virus detectado en estas partículas.ABSTRACT : The new coronavirus pneumonia, COVID-19, has become a global public health problem. From the first months of the pandemic, all aspects that may be related to the disease are being investigated, from its causes to its treatment, through the study of risk factors that can aggravate its incidence and lethality. In addition to the dynamics of person-to-person transmission of the new respiratory virus, the role of environmental factors in accelerating the spread of SARS-CoV-2 and its lethality has recently been studied. Currently, air pollution is the leading environmental cause of illness and premature death in the world. The present work aims to analyze the hypothesis that air pollution (especially PM2.5 and PM10), resulting from a combination of factors such as meteorological data, the level of industrialization and regional topography, can act as a carrier of infection and as a factor aggravating the impact on health of the COVID-19 disease. During the different phases of the state of alarm, an immediate decrease in the main atmospheric pollutants has been observed. For its part, contamination seems to be related to the severity in the symptoms of Covid-19 patients. Finally, although most studies highlight that particulate matter can act as a vector for SARS-CoV-2, the viability of the virus detected in these particles is not yet knownGrado en Medicin