PA measles outbreak tops 1,000 cases, largest since disease was eliminated

Pennsylvania reported 1,066 outbreak-linked cases on Wednesday.

The short version

• Pennsylvania’s explosive measles outbreak is now the largest the US has seen since the highly infectious virus was declared eliminated in 2000.
• With well over 1,000 cases, it’s the largest on record since 1991.
• Pennsylvania’s health officials reported 1,078 measles cases in all of 2026 as of this afternoon.

What happened

That includes 12 cases in January and March, with the remaining 1,066 cases since April , when the current outbreak began. The tally includes 145 cases recorded in the last seven days and 74 identified since the previous update on Monday.

Why it matters

Health officials noted that 40 of the 74 cases added today were from more than two weeks ago and are just now being recorded.

Summary by Nerd News Network. Read the full article at Ars Technica via the links above and below.