As measles cases in West Texas are still on the rise two months after the outbreak began, local public health officials say they expect the virus to keep spreading for at least several more months and that the official case number is likely an undercount.

The measles outbreaks in West Texas and New Mexico have surpassed a combined 350 cases, and two unvaccinated people have died from measles-related causes. Measles is caused by a highly contagious virus that's airborne and spreads easily when an infected person breathes,

As new cases are reported, our maps and illustrations show the spread of the virus and how infections can run through a community.