Green’s Dictionary of Slang

(Aus.) crabs (body lice).

1967		‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xxxiv 4/3: dibs and dabs: Crabs.
1983		R. Aven-Bray Ridgey-Didge Oz Jack Lang 9: He was new to the pitch and toss, but he had heard that the dibs and dabs in the area could jump forty feet.
1990		Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Dibs and dabs. Body lice.
2002		Pete’s Aussie Sl. Home Page 🌐 dibs and dabs: crabs (body lice).