Why why do cuts from coral, oyster shells and fish spines always seem to get infected? Other than not getting cut in the first place, are there ways of preventing infection? - M.
Corals are hard, sharp and brittle, which means they create irregular wounds with lots of crevices and
injured tissue with poor bloodflow where bacteria flourish.
Coral scrapes also deposit calcium dust in the skin, which causes inflammation and pain. Like most marine animals, including fish, corals are covered in slime. Surprisingly, slime is actually mostly sugar with some proteins and bacteria mixed in. Even white blood cells and antibodies find it hard to cope with and bacteria gain a strong foothold.
Two tips for coral wound care: use a safety-pin to pluck out embedded bits of coral; and use hydrogen peroxide, diluted with water, to apply to the fresh wound. The resulting foam will help lift out coral dust. Combine that with an immediate washout with soap and running water. You may still get infected, but it's more likely to be minor.
Opposite to corals, oyster shells inflict scalpel-like wounds with no debris. So why do they get infected? One reason could be because they are so good at filtering and concentrating bacteria. Shellfish can contain one million bacteria in each gram of oyster meat.
With that many bacteria in a wound the goal is to immediately reduce their number.
