Since the start of the year, 102 cases of measles have been reported in over 14 states.
The Center for Disease Control and Prevention and officials have said the outbreak can be traced to Disneyland in California.
This year, cases have already hit the one-sixth mark of an entire year before.
In 2013 there were 644 total measles cases reported.
Measles has not been fully eradicated. The median number of cases per year throughout 2000 to 2011 was 62.
This measles outbreak has lead to a debate on vaccinations.
Anti-vaccination groups argue harmful side effects can be correlated to vaccines.
Vaccinations are safe and work, the medical and scientific consensus concludes.