Remembering Classic Epidemic Disease Cycles

The Real Truth About Vaccines

Do you remember when most childhood diseases used to happen in classic disease cycles with major epidemics every three to six years?

A “measles year” was worse than a regular year, with more measles cases and deaths than usual. In 1954, there were 682,720 cases of measles in the United States and 518 deaths.

Well, they did…

Remembering Classic Epidemic Disease Cycles

Of course, there were also typically cases each and every year, but then there were also bigger epidemic years.

Why?

In the pre-vaccine era, most people would get sick with these diseases - those were the cases ‘we’ saw each year.

Eventually though, with new people being born, there would be a large enough group of susceptible people around to fuel an outbreak year!

In addition to the epidemic years, all of these diseases still spread seasonally at lower levels each year too.

Interestingly though, these cycles were different for each disease, with:

• measles epidemics occurring in 2 to 3-year cycles

• mumps epidemics occurring in 3-year cycles

• rubella epidemics occurring in 6 to 9-year cycles

• chicken pox epidemics occurring in 2 to 4-year cycles

• diphtheria epidemics occurring in 5 to 7-year cycles

• pertussis epidemics occurring in 3 to 5-year cycles

• polio epidemics occurring in 3 to 5-year cycles

• scarlet fever epidemics occurring in 3 to 6-year cycles

• smallpox epidemics occurring in 5-year cycles

And of course, measles has a short cycle simply because it is so contagious.

What else?

These epidemic cycles were interrupted by vaccines.

They can return though, as except for smallpox, none of these diseases have been eradicated.

And then maybe more folks will remember why the rest of us are vaccinated and protected.

More on Epidemics

• The statistics of epidemic transitions

• Disease Elimination and Eradication

• The calendar of epidemics: Seasonal cycles of infectious diseases