Why is measles surging in London and the US?

Outbreaks tied to low vaccination and fast spread

Several recent clusters have exposed how quickly measles can re‑establish itself when population immunity falls. In north‑east London, more than 60 children — including cases in multiple schools and a nursery — have been infected, prompting urgent appeals from the UK Health Security Agency for parents to check immunisation status before holidays. In the United States, outbreaks have spiked on college campuses and at events; one university reported infections approaching 60 people. Mexico has also recorded thousands of cases since last year and reported deaths, putting its measles‑free status at risk.

Measles is among the most contagious viruses known. It spreads through respiratory droplets and can infect people before symptoms appear, so even brief contact or being in the same room can be enough for transmission. Two main forces are driving the current rise:

• Lower vaccination coverage in pockets of the population, which leaves clusters of susceptible people.
• Increased travel and large gatherings, which create opportunities for the virus to move between communities.

What this means for public health

• Serious complications are possible: measles can cause pneumonia, brain inflammation, hearing and vision loss, and it can be fatal, particularly in very young children and people with weakened immune systems.
• A swift vaccination response curbs spread: the measles‑mumps‑rubella (MMR) vaccine is the primary tool to restore immunity in communities.

Practical steps

1. Check immunisation records and get MMR doses if missing; two doses give the best protection.
2. Keep symptomatic children home and seek medical assessment for fever and rash.
3. Health services may offer catch‑up clinics and advice on travel vaccination.

Vitamin A can help reduce complications in children once measles develops, but it does not replace vaccination. Public‑health authorities are urging rapid action because measles spreads fast and outbreaks that start in one setting can quickly seed others.