Newark and Atlanta wastewater catchments have detected measles viral RNA for two consecutive weekly samples each, according to the WastewaterSCAN network's Friday update. [1] A third metro — provisionally Phoenix, pending a confirmation run — is on the watch list. Wastewater detections do not equal cases, but the network's epidemiologists treat two consecutive positives at separable catchments as a strong signal that case-finding work needs to start.

Yesterday's edition tracked Utah's case count crossing 638 — the largest single-state outbreak since the United States re-earned elimination status in 2000. The wastewater-surveillance question is whether the Utah cluster is being mirrored elsewhere. Two confirmed metros and a third on watch is the answer the PAHO November-7 elimination review will see when it convenes. [2]

The PAHO clock matters because elimination is a regional designation. The Americas were declared free of endemic measles transmission in 2016. Brazil was added back to the endemic list in 2024. A third-metro signal in U.S. wastewater, layered on Utah's outbreak and persistent under-vaccination in three FLDS-adjacent counties, is the kind of data PAHO uses to revisit a country's status.

The CDC's national vaccination dashboard, last updated Wednesday, shows MMR coverage at 89.4 percent for kindergarteners — below the 95 percent herd-immunity threshold for the third consecutive year. [3] The agency has not yet published a national wastewater measles map. WastewaterSCAN, a Stanford-Emory-Verily collaboration, is filling that gap.

-- NORA WHITFIELD, Chicago