Why are we seeing Measles again?

Blog contributed by Kathleen Zimmerman, MD,  Pediatrician

In recent news there have been a multitude of stories on increasing outbreaks of measles.   Measles was almost eradicated by the year 2000, so why are we seeing measles again?

Measles is spread by a very contagious virus.  The virus is spread as easily as influenza virus.  Therefore once a case comes into a community, it quickly spreads to those who have not been vaccinated. Widespread vaccination against measles creates “ herd immunity”.   This is the best protection a community can have from measles outbreaks.  Herd immunity stops isolated cases of measles from spreading into an epidemic.

Vaccination rates have declined in certain areas of the United States and these are the areas that have “holes” in the herd immunity and these are the communities that are having increasing outbreaks of measles.   California’s cases went up from 4 last year to 58 as of this month (and will be higher by the time you see this blog).

Vaccination refusal and delays are most commonly due to misconceptions about vaccine safety.  Also many young parents have never seen measles before and they do not understand that just 50 years ago there were 500,000 Americans infected with measles per year with 48,000 hospitalizations and 500 deaths each year.   The near eradication of this deadly disease 14 years ago was achieved by vaccination.  The return of this disease in exponential numbers is occurring because of vaccine refusal.

It’s important for parents to realize that when they refuse or delay vaccines for their child, they are not only putting their own child at risk, but also their whole community.   This couldn't be exemplified more clearly than in what we are seeing unfold in our country with the current measles outbreaks.