Active Public Health Outbreaks in Missouri: 2024-2025 Report
Executive Summary
Missouri is currently navigating a complex public health landscape characterized by the resurgence of vaccine-preventable diseases and significant foodborne illness investigations. As of early 2025, the state has confirmed seven new measles cases, surpassing the total for the entire previous year. Simultaneously, a massive surge in Pertussis (Whooping Cough) has seen case counts rise by over 700% compared to historical baselines.
While respiratory virus activity (Flu, RSV) remains a seasonal constant, localized outbreaks of Norovirus have forced school closures in Southeast Missouri. Additionally, the fallout from a major E. coli O157:H7 outbreak in late 2024 continues to unfold, with investigations linking local clusters to national lettuce suppliers.
Current Outbreak Threat Levels
Measles Resurgence
In a concerning development for 2025, the Missouri Department of Health and Senior Services (DHSS) has confirmed seven cases of measles early in the year. This cluster represents a sharp increase compared to the sporadic cases seen in 2024. The affected areas include Taney County, New Madrid County, and Cedar County.
Health officials attribute this rise to declining vaccination rates. Data indicates that the statewide MMR vaccination rate for kindergarteners has dropped to approximately 90.1%, falling below the 95% threshold required for herd immunity. In some rural counties, rates are significantly lower, creating "pockets of vulnerability" where the highly contagious virus can spread rapidly.
Measles Cases: 2024 Total vs. 2025 (YTD)
*2025 count already exceeds the previous full year total.
Pertussis (Whooping Cough) Surge
Missouri is experiencing a dramatic spike in Pertussis cases, mirroring a national trend of post-pandemic resurgence. In 2024, the state recorded 422 cases, a staggering 744% increase over the previous year. This trend has persisted into 2025, with case numbers remaining elevated above pre-pandemic baselines.
Contrasting Viewpoints: While some officials cite "immunity debt" from pandemic isolation as a cause, others point to the waning efficacy of the acellular pertussis vaccine and delayed childhood immunization schedules as the primary drivers.
E. coli O157:H7 Investigation
A significant outbreak of E. coli O157:H7 that began in late 2024 continues to have legal and public health reverberations in 2025. The outbreak was initially linked to Andre's Banquets and Catering in St. Louis, affecting over 100 individuals, including students at Rockwood Summit High School. Several victims were hospitalized with Hemolytic Uremic Syndrome (HUS).
Source Controversy: While initial reports focused on the caterer, subsequent genomic sequencing and lawsuits filed in 2025 have implicated a broader supply chain issue. Attorneys for the victims allege the contamination originated from romaine lettuce supplied by Taylor Farms, linking the Missouri cases to a multi-state outbreak. This shifts the narrative from a local food handling error to a national agricultural safety failure.
Outbreak Impact
- 100+ Confirmed Illnesses
- 13+ Hospitalizations
- Multiple cases of Kidney Failure (HUS)
- Status: Active Legal & Supply Chain Investigation
Other Active Clusters
Norovirus in Schools
Location: Southeast Missouri (Chaffee, Charleston, New Madrid)
Early 2025 has seen a wave of school closures driven by a "triple threat" of Norovirus, Flu, and RSV. Unlike reportable diseases, Norovirus tracking relies on outbreak reporting from institutions. The virus has caused significant absenteeism, forcing districts to switch to virtual learning temporarily.
Congenital Syphilis
Trend: Multi-year Sustained Increase
Missouri continues to battle a long-term epidemic of syphilis. Of particular concern is the rise in congenital syphilis (transmission from mother to child), which has seen a 259% increase in early syphilis cases over the last decade. This remains a critical, ongoing public health priority for the state.