New Delhi, April 29 -- It takes just a spark to start a wildfire, and when it comes to measles, the embers are already glowing.

A new modelling study published in Jama sounded the alarm: recent drops in childhood vaccination rates could reignite diseases that were nearly extinguished.

The researchers used a simulation to predict the effect of falling vaccination coverage for measles, rubella, polio and diphtheria. Even at current coverage, measles alone could soon infect more than 850,000 people in the US every year, leading to over 2,500 deaths annually.

The study also warned how quickly the situation could get worse. A further 10% drop in vaccination rates could lead to more than 11 million cases annually.

Measles is particularly co...