Here’s a brief new synthesis of which non-pharmaceutical interventions work best and why (sometimes, where) they work. It was published on February 22 in the Journal of the American Medical Association.
Investigations of COVID-19 outbreaks have shown that the factors influencing the risk of transmission vary across settings. However, these local factors occur in several well-established patterns that can be prevented when identified. For example, compared with well-ventilated outdoor spaces, the risk of infection is higher in poorly ventilated indoor spaces when there is prolonged duration of close contact (within 6 feet of someone for ≥15 minutes over a 24-hour period coupled with limited physical barrier to viral transmission because of inconsistent use of masks. The context and intensity of exposure are key in the spread of SARS-CoV-2. Large outbreaks or superspreader events have generally been characterized by a confluence of these factors, such as crowded indoor spaces combined with lack of mask use.4 Living and working environments that are characterized by such factors may also contribute to the greater incidence of COVID-19 associated with race/ethnicity, poverty, and zip code.
Nothing new. But a helpful integration of findings and research citations. Just to be explicit: from a Supply Chain Resilience perspective, viral transmission is an important element of demand dynamics. Non-pharmaceutical interventions are a form of demand management. We want to avoid excess demand for services by hospitals and, especially, intensive care units. Sudden and sustained demand beyond existing capacity is one of the most dangerous threats to any supply chain.