New evidence on SARS-CoV-2 transmission: implications for preventive measures

  • Andrea Spinazzè DiSAT - Università degli Studi dell'Insubria
  • Andrea Cattaneo Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell’Insubria, Como
  • Domenico Maria Cavallo Dipartimento di Scienza e Alta Tecnologia Università degli Studi dell’Insubria, Como


Considering the persistence of the current pandemic situation and considering the evolution of knowledge about the modes of transmission of SARS-CoV-2, a serious reflection on the validity of the available guidelines is necessary. In fact, in some cases, available operating procedures appear to be outdated, as they are based on a precautionary approach and on the knowledge produced during the “first wave” of infections and not compared to the latest available evidence, which instead contributed to expanding knowledge of the mechanisms of contagion. In particular, considering that the risk of transmission of SARS-CoV-2 by contact with contaminated surfaces does not represent a relevant risk of transmission in most living and working environments, it is necessary to adopt a more balanced perspective: the lack of clarity on the risks posed by transmission through fomite - compared to the much greater risk represented by transmission through aerosols and droplets - can have significant implications. Considering the available evidence, it would probably be more effective to use more resources to intervene on the ventilation systems of indoor living and working environments to reduce contagion through aerosols and droplets.


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