Active Public Health Outbreaks in Pennsylvania: November 2025 Status Report
As of late November 2025, Pennsylvania is managing a complex public health landscape characterized by the seasonal resurgence of respiratory viruses and specific, localized outbreaks of vaccine-preventable and zoonotic diseases. While the Pennsylvania Department of Health (PA DOH) reports that overall emergency department visits for respiratory illnesses remain below critical thresholds, data from late 2025 indicates significant "upticks" in specific viral activities and ongoing surveillance alerts for avian influenza and measles.
Current Outbreak Alerts (Nov 2025)
- Infant Botulism Multi-state advisory linked to powdered formula (Nov 19).
- Avian Influenza (H5N1) 6 commercial flocks in Lancaster Co. infected (Oct 2025).
- Measles Surge to 10-49 estimated cases; community spread concerns.
- Pertussis Sustained activity following the major 2024 spike (2,800+ cases).
Respiratory Virus Trends (Season to Date)
Data Source: PA DOH & Surveillance Reports (Sept 28 - Nov 2025)
Zoonotic & Environmental Threats
Avian Influenza (HPAI): The H5N1 virus remains a persistent threat to Pennsylvania's agriculture. In October 2025, six commercial poultry flocks in Lancaster County confirmed infections, affecting nearly 58,000 birds. While the virus has devastated poultry (over 7 million birds affected in PA since 2022), recent testing in November 2025 confirms that no dairy cattle in the state have tested positive, contrasting with outbreaks in other regions.
E. Coli & Water Safety: Earlier in the 2025 season, high levels of E. coli were detected in tributaries of the Susquehanna River and at Raccoon Creek State Park, leading to swimming closures. While recreational water risks have subsided with the cooler weather of November, a recall of raw milk in July 2025 due to E. coli contamination highlights the ongoing risk associated with unpasteurized dairy products in the state.
Conflicting Viewpoints: Official Data vs. Community Reports
The Lag in Reporting: While the PA DOH dashboard currently classifies influenza activity as "low," local health systems and news outlets in Western Pennsylvania are reporting a distinct "uptick" in cases as of early November. This discrepancy often reflects the time lag between clinical diagnosis and state-level aggregation.
Vaccination Gaps: Public health officials cite "vaccine fatigue" and dropping herd immunity rates (now below 95% in some counties) as the primary driver for the resurgence of measles and pertussis. Conversely, some community groups in affected areas attribute the spread to the cyclical nature of these pathogens rather than solely vaccination coverage.
Vaccine-Preventable Disease Resurgence
Measles: Pennsylvania is currently monitoring a surge in measles cases, with estimates ranging between 10 and 49 confirmed infections for the year 2025. This marks a significant increase compared to the previous year. The outbreaks have been largely concentrated in pockets of unvaccinated populations, prompting the Philadelphia Department of Public Health to issue continued vigilance advisories through late October and November.
Pertussis (Whooping Cough): Following a massive spike in 2024 where Pennsylvania led the nation with over 2,800 cases, the state continues to see elevated pertussis activity in 2025. Health alerts remain active for schools and universities, particularly in the Pittsburgh and Philadelphia metro areas, where transmission has been highest among adolescents.