Active Public Health Outbreaks in Massachusetts
Infant Botulism Outbreak (Formula Linked)
As of November 26, 2025, federal and state officials are investigating a multistate outbreak of infant botulism linked to ByHeart Whole Nutrition infant formula. Massachusetts has confirmed 2 cases among infants.
Outbreak Statistics (National vs. MA)
Source: FDA & CDC Investigation Update (Nov 26, 2025). All 37 affected infants nationally were hospitalized.
Respiratory Viral Season: The "New" Tripledemic
As of late November 2025, Massachusetts is entering its peak respiratory virus season. While overall severity remains "Low" on the DPH dashboard, specific viral strains are driving concern among public health officials.
Influenza (H3N2 Variant)
A new H3N2 subclade has emerged, showing significant mutations that may impact vaccine efficacy.
Of 160 recent Flu A cases, 115 were H3N2.
COVID-19 & Wastewater
Wastewater surveillance (MWRA) indicates a rising "Winter Wave" expected to peak in December.
Data as of late Oct 2025. Trend is upward.
Vaccine-Preventable Diseases
Measles: While the U.S. has seen a surge in 2025 (surpassing 2024 totals by March), Massachusetts has maintained high control. Only isolated travel-related cases have been reported (e.g., March 2025, June 2025 exposure in Boston), contrasting with large outbreaks in other states like Texas.
Pertussis (Whooping Cough): Following a major spike in 2024 where cases returned to pre-pandemic levels, pertussis activity remains a "high index of suspicion" priority for DPH, particularly among adolescents (11-19 years old).
Current Risk Levels (Nov 30, 2025)
Data Contrast: Official vs. Emerging
- Flu Severity Official DPH reports classify current severity as "Low," yet clinical data shows the H3N2 strain accounts for 72% of cases, a mutation profile that often precedes high-hospitalization seasons.
- Measles Risk National news highlights a "Surge" (>300 cases US), but MA data shows <5 cases locally, highlighting the protective "firewall" of the state's high vaccination rates compared to national averages.
2025 Arbovirus Recap
Season concluded with first frost.
(2025)
(2024)
Mosquito
Unlike the active 2024 season which saw 4 human cases and curfews in towns like Oxford and Webster, 2025 remained largely quiet for human transmission despite early mosquito positives.