naomba mnisaidie kutafsiri hii sound effect ya whoosh kwa lugha yetu mama.
That word is onomatopoetic, which means it isn't necessarily English word. I would,
1. use it as is
2. swahilinise it as "wuushi"
Remember, in English there are many ways in which onomatopoia can be used, e.g., we can use woosh, swish, swoosh, etc to refer to wind
Shaa! Spidi mia ishirini.