By Anthony Lee, MD

Faculty, Harvard Medical School

As we make our way through this pandemic, the large number of cases in the United States has caught our attention and prompted much discussion. In Part 6 of this series, we continue to see Ireland and the UK consistently decline in number of daily deaths. If we assume that the pandemic in these countries is on the mend, tracking the number of cases is no longer fruitful.

Likewise, Italy, Belgium, and Northern Ireland have not seen increases in daily new cases, or deaths, over the last 3-6 weeks so we will no longer follow them. However, as these countries begin easing lockdown measures, this may change.

Please note that this report will only consider confirmed COVID deaths.

As explained in Part 4 and Part 5, it's the case density (cases per 100,000 people) that matters and not the total number of cases. The higher the number of cases per 100,000 people, the more dangerous that location is. For example: riding in a subway car. If a specific location has a high case density, it's more likely that riding on a subway car in that location will have more infected passengers compared to a subway car in a different location.

In Figure 1, Plots of New York City and New York State are compared to Massachusetts, "The Rest of the United States" (US minus NYS or US-NYS), and Sweden.

On the left of Figure 1, Massachusetts' cumulative number of cases continues to rise. On the right of Figure 1, the number of daily new cases in Massachusetts is declining. However, its daily new cases now exceed that of NYS, which started to decline 15 days prior.