April 17, 2020
Absent a vaccine for COVID-19, government leaders have urged social distancing and implemented stay-at-home orders. These strategies have been shown effective in slowing the virus’ spread, according the Centers for Disease Control and Prevention (CDC), whose Morbidity and Mortality Weekly Report released Tuesday looks the cumulative effective of public policies to change behavior.
The report’s authors examined data from four major cities with high COVID-19 cases: New York, San Francisco, Seattle and New Orleans to correlate community mobility—a proxy for social distancing—with the timing of public orders.
In all four cities, the percentage of residents leaving their homes between Feb. 26 and April 1 decreased with additional public policy declarations. Nearly 80% of residents in each city were leaving home on Feb. 26. By April 1, the percentages dropped to:
- 42% in New York;
- 47% in San Francisco;
- 52% in Seattle; and
- 61% in New Orleans.
In each city, emergency declarations were the first policy issued and did not result in significant social distancing. Changes in behavior occurred after government leaders implemented a combinations of policies—such as limits on gatherings or school closures—and after the Trump Administration announced “15 Days to Slow the Spread” on March 16.
Data sources for the report were Google alerts; Google searches for news media coverage of state and local COVID-19 orders and proclamations; and searches of state, county, parish and city government websites for official copies of each order.