Contemporary Measles Virus Isolates Available

A multistate measles outbreak began in January 2025, primarily affecting close-knit communities with low vaccination coverage in New Mexico, Oklahoma, and Texas. As of November 21, 1,753 measles cases had been reported in the United States in 2025. Of these, 87% (1,530 cases) are associated with the ongoing outbreak. This represents an approximately 540% increase compared to the 285 cases reported in all of 2024.^1,2

Recent investigations have identified mutations in the nucleoprotein (NP) gene of certain genotype D8 isolates. These mutations affect the annealing site of the reverse primer used in the Centers for Disease Control and Prevention’s (CDC) RT-rPCR assay, potentially impacting diagnostic accuracy.³

BEI Resources is now offering two contemporary measles virus isolates linked to the outbreak, including one with mutations in the NP gene. gRNA derivative products will also be available soon.

References:

1. “Measles Cases and Outbreaks.” Centers for Disease Control and Prevention, https://www.cdc.gov/measles/data-research/index.html. Accessed 21 November 2025.

2. Godoy, M. “U.S. measles cases hit highest level in 33 years, CDC reports” NPR, 9 July 2025, https://www.npr.org/sections/shots-health-news/2025/07/09/nx-s1-5461155/measles-outbreak-cdc-vaccination-health. Accessed 21 November 2025.

3. Pérez-Rodríguez, F.-J., et al. “Identification of a Measles Variant Displaying Mutations Impacting Molecular Diagnostics, Geneva, Switzerland, 2023.” Euro Surveill. 29 (2024): 2400034. Pubmed: 38304951.

Image Alt Text: Colorized transmission electron micrograph of a measles virus particle (red). Microscopy by CDC; layout, colorization and visual effects by NIAID. Credit: CDC/NIAID (CDC/NIAID/CC BY 2.0)

Image Credit: Colorized transmission electron micrograph of a measles virus particle. (CDC/NIAID/CC BY 2.0)