In early March, a one year-old boy living in a shelter in Chicago was diagnosed with measles. Since measles is a highly contagious virus, more than 2000 shelter residents, many without confirmed histories of measles vaccination, were considered to be exposed. Over the next 3 days, the Chicago Department of Public Health (CDPH) swung into action, vaccinating 882 residents and confirming previous vaccination status in several hundred more, resulting in an estimated measles, mumps, and rubella (MMR) vaccine coverage of 93%. Nonetheless, in the next two months, 57 more cases of measles had been diagnosed among people residing in or having contact with residents of the shelter. A dynamic disease simulation model from the Centers for Disease Control and Prevention (CDC) estimated that in the absence of mass vaccination and case finding by CDPH, there was a 69% probability that this single infection would have led to more than 100 new measles cases.
The outlook for measles in the next decade in the U.S. is mixed, at best. Driven by the COVID-19 pandemic, vaccine skepticism and anti-vaccine sentiment has led to increases in religious and philosophical exemptions, causing the national kindergarten vaccination rate to fall to 93% in 2021-2022. Each percentage point decline increases the risk of a measles outbreak, as illustrated by the CDC's National Center for Immunization and Respiratory Diseases, with 93% MMR vaccination coverage associated with a 36% risk that a single infectious child could create an outbreak at a school with 100 children.
Unfortunately, decreasing childhood vaccination rates were not the only negative effect of the pandemic. The compelling PBS mini-series "The Invisible Shield" juxtaposes the historical successes of public health officials in controlling diseases and saving lives with the angry and occasionally violent pushback they received for ordering business closures and masking mandates to slow the spread of COVID-19. A recent Health Affairs article documented 112 judicial decisions from 2020-2023 that constrained public health's legal powers. As a result, the health commissioner for Columbus, Ohio was unable to close a daycare center where a measles case was reported in 2021, and a county in Michigan came close to shutting down the entire county health department over a dispute about masks.
An even bigger threat to public health is awaiting a decision from the Supreme Court:
On January 17, 2024, the US Supreme Court heard oral arguments in 2 combined cases, Loper Bright Enterprises v Raimondo and Relentless, Inc v Department of Commerce, that will determine the fate of Chevron deference, a bedrock principle of administrative law that obligates courts to defer to an agency’s reasonable interpretations of ambiguous statutes. ... Agencies like the FDA and CMS have, for decades, regulated medicine and public health in reliance of these principles.If the Supreme Court decides that this deferential statutory framework is unconstitutional, it would effectively open every federal health regulation that does not derive directly from specific legislative language (the vast majority of thousands and thousands of regulations) to a lawsuit, and it would put the burden on a dysfunctional Congress to account for "all possible regulatory scenarios and unforeseen circumstances" in writing unambiguous legislation. This would be a disaster.
I wonder how federal and state governments would respond if public health actions became necessary to protect people from H5N1 ("bird flu"), which so far has only been confirmed in 3 dairy workers this year but has likely infected many more? So far H5N1 has only caused mild symptoms in humans, but the fact that this virus has spilled over from cows to people and little surveillance is being done in to track its spread in either population is worrisome.