Aquaphobia is an abnormal and persistent fear of water. Aquaphobia is a specific phobia that involves a level of fear that is beyond the patient's control or that may interfere with daily life. People suffer aquaphobia in many ways and may experience it even though they realize the water in an ocean, a river, or even a bathtub poses no imminent threat. They may avoid such activities as boating and swimming, or they may avoid swimming in the deep ocean despite having mastered basic swimming skills. This anxiety commonly extends to getting wet or splashed with water when it is unexpected, or being pushed or thrown into a body of water.
Phobias (in the clinical meaning of the term) are the most common form of anxiety disorders. A study by the National Institute of Mental Health (NIMH) found that between 8.7% and 18.1% of Americans suffer from phobias. Broken down by age and gender, the study found that phobias were the most common mental illness among women in all age groups and the second most common illness among men older than 25.
Of the simple phobias, aquaphobia is among the more common subtypes. In an article on anxiety disorders, Lindal and Stefansson suggest that aquaphobia may affect as many as 1.8% of the general Icelandic population, or roughly one in fifty people.
Medical professionals indicate that aquaphobia may manifest itself in a person through their specific experiences or due to biological factors. Some people may develop the phobia as a reaction to a traumatic water experience---a near drowning or other such event. Others may have simply failed to have acquired experience in the water through casual events like swimming or boating events due to cultural factors. Other individuals may suffer from an "instinctive reaction" to the water which arises separate from any observable factors. They have a gut reaction that limits their fundamental comfort level in any sort of casual water activities, such as swimming. Other sufferers may experience discomfort around the water without falling into any of the previous three categories.
Many people mistakenly refer to aquaphobia as 'hydrophobia'; hydrophobia is in fact a symptom of later-stage rabies, and manifests itself in humans as difficulty in swallowing, fear when presented with liquids to drink and an inability to quench one's thirst. "Hydro-" is Greek and "aqua-" Latin, both meaning "water". Most phobias have a Greek prefix, but because the word "hydrophobia" was first used to describe late-stage rabies, the term "aquaphobia" using a Latin prefix was used to prevent confusion. Cymophobia, the fear of waves, is normally associated with aquaphobia.