The first paper deals with a subject that I am endlessly fascinated with: how does this virus get transmitted and how hardy is it? It comes from a study in Italy on the potential role of air pollution particles. (Medrxiv Paper) The authors did not believe that droplet transmission alone could explain the differential rate of spread in Italy’s regions. So they analyzed the effect of levels of air pollution. They concluded that regions with greater levels of air pollution had more coronavirus cases. Of course, this could be because the air pollution weakens lungs and makes people more susceptible. The authors do cite some research suggesting that the virus could survive and travel on air pollution particles for some time.
The IMHE model from the University of Washington has appropriately taken a beating from a number of researchers, particularly since it had very high initial estimates of deaths and has since changed those wildly over several weeks. A critique in the Annals of Internal Medicine gives multiple reasons for treating that model with great caution. (IMHE Critique) The authors note that the model does not have an epidemiologic underpinning. They also suggest that it assumes that suppression of spread measures work the same everywhere. They make the now obvious observation that there was little accurate information to underpin the assumptions made on infection, transmissibility and death rates. Finally they note that the model has a huge range of uncertainty and even that may understate how unreliable its projections are.
Finally, a useful piece of research on the potential costs and benefits of various mitigation of spread measures, which is so important given the economic damage we are experiencing. (Medrxiv Paper) This was a meta-review of other research looking at the effectiveness or cost-effectiveness of various mitigation of spread tactics. Of 34 papers, high quality evidence was only available to support the effectiveness of hand washing and face masks. Only lower quality evidence existed for any other measure. The most cost-effective out of this group were contact tracing and isolation and PPE. Home quarantines were less cost-effective. Social distancing and workplace closure measures were the least cost-effective. This is a well-done review which actually dares to suggest that perhaps we should consider the cost of our severe lockdowns.