Measles
From a pediatric perspective, measles remains a significant public health concern in the United States despite being declared “eliminated” in 2000. In recent years, pediatricians across the country have seen a concerning resurgence of measles cases and outbreaks, primarily affecting unvaccinated children and adolescents. The Centers for Disease Control and Prevention (CDC) reports that the United States has already experienced substantially elevated measles activity in 2025 and 2026, with thousands of confirmed cases nationwide and multiple outbreak clusters involving school-aged children.
Measles is one of the most contagious infectious diseases known. The virus spreads easily through the air when an infected person coughs or sneezes and can remain airborne for up to two hours. Measles typically begins with cold-like symptoms before progressing to a characteristic rash. In children, symptoms usually appear 7–14 days after exposure. Common signs and symptoms of measles include: high fever — often one of the first symptoms and may rise above 104°F (40°C), cough, runny nose (coryza), red, watery eyes (conjunctivitis), fatigue and irritability, and decreased appetite. A classic early finding is the appearance of Koplik spots, which are tiny white or bluish-white spots inside the mouth on the inner cheeks. These may appear 1–2 days before the rash. The measles rash usually develops about 3–5 days after the fever begins. The rash starts on the face and behind the ears, spreads downward to the neck, trunk, arms, and legs. It appears as flat red spots, sometimes with small raised bumps. Rash areas may merge together as it spreads. Children with measles are usually contagious from about 4 days before the rash appears until 4 days afterward. Some children develop serious complications, especially infants, unvaccinated children, and immunocompromised patients. Complications may include: ear infections, diarrhea, pneumonia, dehydration, encephalitis (brain inflammation), and rarely, death.
Parents should contact their pediatrician promptly if a child: has symptoms consistent with measles, has been exposed to someone with measles, develops difficulty breathing, lethargy, dehydration, or persistent high fever. Infants under 12 months of age, who are too young to be fully vaccinated, are particularly vulnerable.
Most recent U.S. measles cases have occurred in individuals who were either unvaccinated or whose vaccination status was unknown. According to CDC data, approximately 92–93% of reported cases in 2025–2026 fell into these categories. Pediatricians are especially concerned because routine childhood vaccination rates have declined below the 95% threshold needed to maintain strong community (herd) immunity in many areas. National kindergarten MMR vaccination coverage has decreased from over 95% in 2019–2020 to approximately 92.5% in recent school years, leaving hundreds of thousands of children susceptible to infection.
The measles, mumps, and rubella (MMR) vaccine remains highly effective and safe. Two doses of MMR provide approximately 97% protection against measles. From a pediatric healthcare standpoint, maintaining high vaccination coverage is critical not only to protect individual children, but also to safeguard infants, immunocompromised patients, and others who cannot receive vaccines themselves. Pediatric practices continue to emphasize timely childhood immunizations, early recognition of symptoms, and rapid public health response to suspected cases in order to prevent further outbreaks and protect community health.
