We still don’t have sufficient data on the severity (aka virulence) of omicron. Here is a very helpful overview from Nature on the accumulating evidence after three weeks of intense, but necessarily incomplete analysis. As my other posts reveal, I perceive that even if omicron is less severe than Delta (or even Alpha), it is so insistently contagious that there is the potential for health care systems to be overwhelmed by a triple whammy of delta, seasonal flu, and complications of omicron. While this risk should surely spur vaccinations, boosters, and non-pharmaceutical mitigation measures, we do not yet have the data to confidently know what to expect in January and February. By Christmas eve we may have better data from South Africa, United Kingdom, and Denmark. A whole range of options for the United States is set out in scenario-based projections from the University of Texas at Austin, COVID-19 Modelling Consortium.