New York’s Recovery Drove National COVID-19 Case Reduction

Sarah Hamersma

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The trend in new daily U.S. cases of COVID-19 looked like it was improving during April and May and then took a sudden turn in what some started calling the “second wave.” The first graph (A) shows the trend in new cases for the U.S. overall that gave the impression that the U.S. was beating COVID-19. However, it turns out that the progress we observed nationally was driven almost entirely by large reductions in cases in New York.  The second graph (B) breaks out NY’s case trends from the rest of the U.S., reminding us of that painful period when NY was home to about one-third of the daily increase in national cases.  New York’s strong actions to stop the spread led to dramatic reductions in daily cases, and these reductions drove what appeared to be a downward national trend.  Without New York included, the national trend in April and May was nearly flat, showing a crucial reduction in growth due to lockdown actions but little evidence of true success in defeating the virus. Community spread outside NY hovered remarkably close to 20,000 new cases per day for all of April and May. This helps explain why the re-opening of states under these circumstances has led to immediate exponential growth in cases. What we are seeing is not a “second wave”, but instead a continuation of case increases across several U.S. states. Without the strong action taken in NY, the country as a whole would be seeing an even larger surge than what we are currently seeing. It is important for NY to remain vigilant as it continues through its various phases of reopening.

Figures A and B: New Daily Positive Cases in US and New Daily Positive Cases in NY versus rest of US

About the Author
Sarah Hamersma (sehamers@maxwell.syr.edu) is Associate Professor of Public Administration and International Affairs and a Senior Research Associate with the Center for Policy Research in the Maxwell School of Citizenship and Public Affairs at Syracuse University.

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