The United States measles crisis continues to deepen. As of July 16, 2026, the CDC has confirmed 2,260 measles cases across 44 states and jurisdictions, with 34 separate outbreaks and a pace that puts the country on track to far exceed 2025's total of 2,289 cases, itself the highest annual count in 33 years. With summer travel at its annual peak and the school year still months away, public health officials warn that the next several weeks represent one of the highest-risk windows for additional importation and outbreak events.
A striking 93% of confirmed 2026 cases, or 2,108 of 2,260, are outbreak-associated, and most involve people who were unvaccinated or whose vaccination status was unknown.
Why This Matters
Measles is among the most contagious infectious diseases known to science. One infected person can transmit the virus to nine out of ten susceptible people in close contact, and the virus can linger in an airspace for up to two hours after an infected person has left. For communities where childhood MMR vaccination rates have slipped below the 95% threshold needed for herd protection, a single importation event can cascade into a sustained outbreak within weeks.
Summer travel creates exactly those conditions. Airports, theme parks, summer camps, and international travel corridors all bring together large numbers of people, including those who are unvaccinated by choice or because they are too young for the vaccine, like infants under 12 months. The CDC has specifically warned state health departments that summer travel patterns will drive additional importation events in the weeks ahead.
What We Know So Far
According to the CDC's measles tracker, updated July 16, 2026, cases have been reported in Alabama, Alaska, Arizona, California, Colorado, Connecticut, the District of Columbia, Florida, Georgia, Idaho, Illinois, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, New Jersey, New Mexico, New York City, New York State, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, Wisconsin, and Wyoming. Fifteen of the 2,260 cases were reported among international visitors to the United States.
The 34 new outbreaks reported in 2026 come in addition to ongoing outbreaks that began in 2025. The largest 2026 clusters have been centered in Utah (400-plus cases, ongoing), with the South Carolina outbreak exceeding 600 cases before being declared over in April after 42 days of no new linked cases.
For full-year 2025, a total of 2,289 confirmed measles cases were reported, according to the CDC, itself a 33-year record. With 2,260 already confirmed through mid-July 2026, the current year is within reach of that full-year total well before summer ends.
Where the Risk Is Highest
Communities with the greatest measles vulnerability in 2026 share identifiable characteristics. According to KFF health policy data, national MMR vaccination coverage for kindergartners has continued a multi-year decline. Local pockets well below the 95% herd immunity threshold exist in specific school districts in Texas, Utah, Ohio, Indiana, and several other states.
The American Academy of Pediatrics identifies communities with the highest risk as those with kindergarten MMR vaccination rates below 95%, high rates of religious or philosophical vaccine exemptions, significant recent immigration from countries with active measles outbreaks, and proximity to major international airports or travel hubs.
Urban areas with major international airports represent high importation-risk corridors during summer peak travel. New York City, Los Angeles, Miami, Chicago, Dallas, Houston, and San Francisco are the metro areas most exposed to imported cases during this period.
What Doctors and Experts Say
"Vaccination is our most powerful tool," the CDC states in its measles guidance, noting that two doses of the MMR vaccine are approximately 97% effective against measles. The agency reiterates that 93% of 2026 confirmed cases involved people who were unvaccinated or whose vaccination status was unknown.
Pediatric and public health experts have pointed to the convergence of two trends accelerating the crisis: declining MMR vaccination rates in kindergartners over the past several years, and the growth of clustered unvaccinated communities, where even a single imported case can ignite a large outbreak. A Common Health Coalition analysis found that a 1% decrease in childhood MMR vaccination rates could result in 17,000 measles cases, 4,000 hospitalizations, and 36 preventable deaths annually.
What the Evidence Shows and What It Does Not
MedicalDaily Evidence Check
- Surveillance source: CDC measles case tracker, updated July 16, 2026
- Confirmed cases: 2,260 in 44 jurisdictions
- Outbreak-associated cases: 93% (2,108 of 2,260)
- Deaths in 2026: None confirmed as of the most recent CDC update
- Hospitalizations: Approximately 6% of 2025 cases were hospitalized; 2026 hospitalization data pending complete reporting
- Vaccine efficacy: Two MMR doses approximately 97% effective against measles (CDC)
- What it does not show: Whether the U.S. will formally lose measles elimination status; that determination depends on sustained transmission chains over a rolling 12-month period
- What readers should know: MMR vaccination is the single most effective protective step; checking your child's vaccination record before summer travel is urgent
Who Faces the Greatest Risk?
Health officials say the populations facing the highest measles risk in 2026 are:
- Unvaccinated children, particularly those under 12 months who are too young for the first MMR dose
- Children who have received only one MMR dose
- Adults who received only one dose in childhood and were never boosted
- People with weakened immune systems, who may not mount full protection even after vaccination
- Pregnant people who are not immune to measles
- Residents of communities with kindergarten MMR rates below 95%
- Travelers to countries with active measles outbreaks or returning from international destinations during the summer travel season
Symptoms and Warning Signs to Watch For
Measles symptoms typically appear 7 to 14 days after exposure. The progression follows a distinctive pattern:
- Days 1-3: High fever (often above 104 degrees F), cough, runny nose, red and watery eyes
- Days 2-4: Koplik's spots, tiny white spots inside the cheeks, a distinctive early sign
- Days 3-5: A red, blotchy rash beginning on the face and spreading downward to the neck, trunk, arms, legs, and feet
Measles is contagious from four days before the rash appears through four days after, meaning a person is often most contagious before they know they have it. Seek immediate medical care for a child with a high fever and rash, especially following recent travel or known exposure. Call ahead before bringing a potentially infected child to a clinic or emergency room so staff can take appropriate infection control precautions.
What You Can Do Now
- Verify that your children are up to date on MMR vaccination: two doses, with the first at 12 to 15 months and the second at 4 to 6 years.
- Adults who received only one MMR dose in childhood, or who are uncertain of their vaccination status, should speak with a health care provider.
- Infants traveling internationally before the standard first-dose age can receive an early MMR dose between 6 and 11 months, followed by the standard two-dose series later.
- Check the CDC's current measles outbreak map to understand whether your state or jurisdiction has active cases.
- If you or your child develop fever, cough, runny nose, and rash, especially after travel or known exposure, call a health care provider before visiting in person.
- Avoid travel with unvaccinated infants under 12 months to regions with active outbreaks when possible.
Cost and Access: What Patients Should Know
MMR vaccination is covered by most private insurance plans, Medicaid, and CHIP. Uninsured children can receive the MMR vaccine at no cost through the Vaccines for Children (VFC) program, available at participating clinics and health departments nationwide. Adults without insurance can access MMR vaccination at many local health departments and community health centers at low or no cost.
What Happens Next
The CDC updates its measles case tracker weekly. Public health officials are monitoring whether ongoing outbreaks will sustain transmission long enough to formally trigger a reassessment of U.S. measles elimination status. The fall school year, beginning in August and September, is the next critical inflection point, as unvaccinated children return to classroom settings. MedicalDaily will update this story as the CDC releases new case data.
The Bottom Line
With 2,260 confirmed cases as of July 16, 2026, the United States is on pace to shatter last year's 33-year measles record before the summer ends. The outbreak is not random; it is concentrated in unvaccinated individuals and communities where vaccination rates have slipped. Verifying MMR vaccination status now, before summer travel continues and before the school year begins, is the single most effective protective action families can take.
