Soooo... When I was in Sydney, I had to find a doctor and then a pharmacy to buy a strong antiseptic cream. Beach's sand (more probably sharp bits of shell) created four scratches between two toes of my right foot and after a day and a half, it became slowly red, and it started swelling and oozing. And the smell was not normal. It was also quite painful. It was of course an infection, that the cream fortunately helped curing in less than two days. But now it happens I have a second extremely similar skin infection elsewhere, also happening on sand scratches, and that started very slowly after my last half-day in Sydney, half-day I spent on the same beach while my CSS WG friends were scuba-diving 300m away.

I have never walked barefoot outside of the beach, I had socks inside my light shoes so the only place I could get it from was the beach.

I am therefore seriously questioning the cleanliness of the sand at Manly Beach or worse, the pollution of the water. I read that bacterial water pollution can be rather high in Manly after rainfalls or storms and I wonder if the sand on the main beach is not accumulating that bacterial pollution... In Europe, such spots are regularly disinfected and I wonder if it's the case on Manly beach. All in all, getting not one but two skin infections from sand scratches at the same beach, on two different moments, does not seem to me a coincidence... FWIW, I never had such skin infections before.