The disease presents in three stages, the first and second of which can be treated. The third stage can involve changes to the bones in many parts of the body.
- Primary Yaws (1-3 months from infection) is characterized by ulcers and papillomas.
- In the secondary stage (3 months to 2 years of infection), symptoms include bone swelling and plantar keratosis.
- Tertiary Yaws (up to 10 years after infection) is marked by cartilage destruction and bone malformations.