Infection can develop following an injury or wound to the skin or mucous membranes (such as the inside of the nose or mouth) after a marine life sting or coral scrape. Signs of infection may include:

• Increased pain, swelling, redness, or warmth around the affected area.
• Red streaks extending from the affected area.
• Drainage of pus from the area.
• Fever.

When a jellyfish or Portuguese man-of-war sting breaks the skin, bacteria can enter the skin and an infection can develop. Properly cleaning and caring for the sting site will reduce your risk of infection. Wounds should be cleaned 3 times each day and covered with a thin layer of antiseptic ointment.

Coral scrapes and cuts are common injuries from walking on a beach or from swimming, snorkeling, or diving in warm water. Coral polyps, the soft living material the covers the surface of coral, can be easily torn away from the rigid and abrasive structure underneath by touching, bumping, or falling on coral. When the living material of the coral gets into a wound, it greatly prolongs the wound-healing process, causing inflammation and sometimes a skin infection. Scrapes and cuts from sharp-edged coral tend to take weeks or even months to heal.

It may be hard to tell the difference between a skin reaction to a sting or scrape and an early infection. Both are red and swollen and can be painful. When an area is becoming infected, pain, swelling, and redness usually increase in size as the infection spreads.