The United States has confirmed 1,671 measles cases across 33 states as of April 2 — a 6.1 percent increase from the previous week and a number that is on track to surpass the total for all of 2025.[1]

South Carolina leads with 668 cases. Utah follows with 370. Texas has 175. The three states share a characteristic: vaccination rates below the 95 percent threshold that public health experts say is necessary to prevent measles outbreaks.[3]

Measles is one of the most contagious diseases known to medicine. A single infected person can transmit the virus to 12 to 18 unvaccinated people. The vaccine — two doses of the MMR shot — is 97 percent effective. The math is simple: vaccinate 95 percent of the population and the virus cannot spread. Fall below 95 percent and it will.[4]

The Trajectory

The case count has been climbing steadily since January. On March 13, the total was 1,362. On March 20, it was 1,487. On April 2, it was 1,671. The weekly growth rate of 6.1 percent is not explosive — it is persistent. And persistence is what drives outbreaks to become epidemics.[2]

The CDC is tracking the cases. State health departments are issuing advisories. But the fundamental problem has not changed: too many children are unvaccinated, and the virus is finding them.[5]

The Politics

The states with the lowest vaccination rates are the states with the highest case counts. This is not a coincidence. It is the result of policy decisions — exemption laws that make it easy to opt out, political rhetoric that frames vaccination as a personal choice rather than a public health obligation, and a media environment that gives equal weight to scientific consensus and anti-vaccine misinformation.

The measles outbreak is not a natural disaster. It is a policy failure. And the bill is coming due in hospital pediatric wards across the country.[6]

What Parents Need to Know

Two doses of the MMR vaccine are 97 percent effective at preventing measles. If your child has not been vaccinated, contact your pediatrician immediately. If your child has been exposed to measles, contact your pediatrician before visiting the office — measles is contagious for four days before the rash appears, and waiting rooms are not safe places for exposed children.

The outbreak is not over. It is accelerating. And the only thing that stops it is a vaccine that has been available for 60 years.

-- NORA WHITFIELD, Chicago