This document summarizes monitoring efforts of the wheat stem rust pathogen Ug99 and provides an update on current surveillance activities. Key points include:
- An international monitoring system is in place to track the spread of Ug99 and identify new variants. Surveillance networks have expanded in recent years.
- Ug99 variants with virulence to Sr24 are now detected in several countries. Further movement out of Africa is inevitable without control measures.
- Emerging concerns include potential introduction of Ug99 into South Asia via air currents from the Horn of Africa and detection of Ug99 in Yemen and Australia.
- Challenges remain around political instability, sampling viability, and building pathotyping capacity, but information systems are improving