My 10 month old has what was said to be a yeast infection, but it is primarily on the labia and severly itchy and not better after 2 weeks of medicated butt paste for yeast infections could this be staph or eczema?

Rash: Diaper rash is very common and medicated powder might not be strong enough to tackle it. A prescription medication (nystatin cream/ointment) may be used instead with better relief. If there is a lot of inflammation, steroid preparations for the first 1-3 days may need to be used to reduce it, but no more than that. Staph is less likely and would present with honey colored rash.