The Numbers Behind Measles

Thinking about the measles outbreak in Texas and New Mexico….Since late January, Texas reports 259 cases, 34 hospitalizations, and one death. New Mexico reports 35 cases and one death. In addition, Oklahoma has reports 2 cases.

It probably doesn’t need to be said, but measles is highly contagious. It is spread through coughing and sneezing, expelling moisture into the air. Individuals are contagious 4 days prior and 4 days after a rash appears. One infected individual can spread measles to 18 in a non-immune population. Further, the virus can stay potent in the air up to 2 hours after the contagious individual leaves a room.

What I find of interest is the math. Prior to the vaccination (MMR), close to all children contracted measles. At that time, one contagious individual was only 4 steps away from infecting over 100,000 people and 5 steps from almost 2,000,000. If one person infected 18, and those infected each infected 18, you’ve reached 324. Assuming they each infected 18 more, you have 5832 with measles. Following this trend, the next levels would be 104,976 and then 1,889,568.

Prior to the MMR vaccine, our population wasn't completely non-immune, because many had previously contracted measles and were effectively immune. The numbers don't lie; they illustrate how quickly measles can get out of control in a non-immune population and explain why most baby boomers had measles when they were children.