With Canada, the UK, and several European countries having already lost their measles elimination status, the US is now on the verge of joining these countries with endemic measles transmission just shy of the threshold of losing the status.
Measles elimination is defined as “the absence of endemic measles virus transmission in a defined geographic area for at least 12 months in the presence of a well-performing surveillance system.” A country loses the status after 12 months of consistent measles transmission.
Measles was declared eliminated in the US in 2000, but (as shown in the CDC chart below) the rash of cases since January 2025 – with high numbers still being identified – is significantly impacting that status.
According to the CDC, there were 2,255 confirmed measles cases in the US in 2025, of which 93% of the persons infected were unvaccinated or vaccination status was unknown. As of January 23, 2026, there have already been 416 cases, of which 94% were unvaccinated/unknown. Although no new outbreaks have yet been reported in 2026, 89% of the confirmed 2025 cases are associated with the 49 outbreaks that occurred that year.
These numbers are a significant increase over 2024 when only 285 confirmed cases and 16 outbreaks were reported for the whole year. Additionally, these numbers are likely lower than the actual, as they include only the confirmed cases reported to CDC by jurisdictions, not the probable cases reported.
Measles was declared eliminated in the US in 2000 after widespread use of measles, mumps, and rubella (MMR) vaccine had drastically reduced disease rates. CDC attributes measle’s return to:
- U.S. national MMR coverage among kindergarteners has decreased and is now below the 95% coverage target—with much lower coverage in some communities.
- Global measles activity is increasing, meaning more chances of an unvaccinated person infected with measles abroad returning to the US.
- Although measles is not a seasonal virus, it is very contagious and is often spread over times of high travel (e.g., spring break, summer, holidays) and when unvaccinated persons are in close quarters (e.g., summer camp).
To help stem the tide of measles transmission, businesses are advised to ensure their employees are aware of the increased risk, the contagion, symptoms, and potential seriousness of the disease, and to encourage vaccination for non-vaccinated adults and their children. Most private and government-funded health insurances cover the cost of these vaccines.
COVID Risk Matrix:
Influenza:
Public Health News:
- An outbreak of Hepatitis A is continuing to spread in Cuba, tied to poor hygiene.
- A recent study published by the CDC found that at least 20% of adults surveyed in a nationwide population, who were hospitalized with respiratory syncytial virus (RSV) reported a poor quality of life months after their illness, regardless of their age. Data from this analysis can inform risk communication about RSV in adults and the potential benefits of RSV prevention through vaccination. Relevant to this, acceptance of RSV immunizations in the United States is growing, particularly for older adults, infants, and pregnant women, per a recent survey of 1,600 adults in the US.
- The measles outbreak in South Carolina has topped 700 cases and will likely become the largest measles outbreak in the US.
- In Europe, influenza circulation remains high and is affecting all age groups, but the peak of illnesses appears to have passed in several countries. Influenza A (H3N2) remains the dominant subtype.
