Sixty more measles cases have been identified, bringing the total nationwide number to 940, US health officials reported today.
The new cases, stretching into another state, mark a nearly seven-percent increase in cases from the previous week.
This makes 2019's outbreak the worst since 1994 and since measles was declared eliminated from the US in 2000, the worst since 1992, when more than 2,000 cases were recorded.
New Mexico became the 26th, and most recent, US state to be struck by measles after health officials revealed a one-year-old from Sierra County had fallen ill.
It is the state's first measles case in nearly five years.
The highly infectious disease has been spreading among people who are unvaccinated or live in states that allow non-medical exemptions for vaccines.
The CDC reported on Monday that the total number of measles cases for the year had risen to 940 in 26 states after 60 new cases were confirmed last week
Health experts have warned that the outbreak is not over as the number of cases edges closer to the 1994 total of 958.
That was the highest number since 1992, when the Centers for Disease Control and Prevention (CDC) recorded 2,126 cases.
Public health officials have blamed the measles resurgence on the spread of misinformation about vaccines.
Also to blame, the officials say, are a vocal fringe of parents whom oppose vaccines, believing, contrary to scientific studies, that ingredients in them can cause autism.
Cases have been confirmed in the following US states:
