Stinging Seaweed Disease
(lyngbya)

What is stinging seaweed disease?
Stinging seaweed disease is a skin irritation caused by direct exposure to a poisonous type of algae named Lyngbya majuscula. The fine, hairlike, dark-brown seaweed, commonly known as lyngbya, is distributed worldwide. Lyngbya can be found in certain Hawaiian shoreline waters but only at certain times of the year. The causative agent for swimmer's itch is thought to be one or more toxins produced by the seaweed.

How do you get it?
You can get stinging seaweed disease by direct exposure to the seaweed while swimming or wading in areas where the seaweed grows. Lyngbya can get under the swimsuit next to the skin and produce a rash, usually, but not always, in areas covered by the swimsuit. There have also been outbreaks of stinging seaweed where the rash affected areas of the body not covered by the swimsuit. The reason for this is unknown.

What are the symptoms of stinging seaweed disease?
Symptoms include a red rash similar to a burn, and blister formation with peeling or irritation (itching). Other symptoms include swollen eyes, irritation of the nose and throat, skin sores, headache, and fatigue. The rash frequently appears in the genital and anal areas. In men with genital (sex organ) involvement, swelling of the scrotum is common.

When do symptoms start?
Symptoms may begin several minutes to several hours after exposure to the algae, and typically last 4 to 48 hours. In more serious cases, skin sores may appear, which can last up to 12 days.

What is the treatment for this disease?
The rash can be treated as a sunburn using wet towels and soothing creams may be used to alleviate symptoms.

How do you keep from getting it?
The only sure way to avoid stinging seaweed disease is to avoid swimming in the ocean. However, if you choose to swim in the ocean, avoid waters where stinging seaweed has been reported.

Shower or bathe with lots of soap and water promptly after swimming. Thoroughly wash swimsuits, towels, and any associated swim gear to get rid of any attached algae.