Frequent hand washing is one symptom of obsessive-compulsive disorder. OCD has been classified by the World Health Organization as an important cause of illness-related disability. It can affect people's work, relationships and social life in many ways. [Photo by Song Chen / China Daily]

Many people in China may suffer from obsessive-compulsive disorder without knowing or admitting to it. Experts tell Wang Hongyi that these patients need professional help.

On, off; on, off; on, off. Even Xiao Tao (not her real name) herself doesn't know how many times she has to turn the water tap on and off. She also has to lock the door many times or her mind will wander and she will worry that something bad will happen.

The 28-year-old woman is "extremely tidy and clean" - she has to wash her hands frequently, often hundreds of times a day.

"I always fear contamination and I have to keep cleaning myself, but this is destructive to my life and it's abnormal," says the young woman, who has been diagnosed with obsessive-compulsive disorder.

The term "OCD" is frequently heard in daily life, but many people who use it to describe themselves use it inaccurately, to represent quirky habits, such as being addicted to their cellphones, tablets and other digital devices. Many know very little about OCD.

It is a mental problem where people have recurring obsessions and compulsions, which develop to such an extent that those actions become a handicap to their daily life. Typical symptoms include recurring obsessive thoughts, images, or urges, and repetitive compulsions in response to the obsession. One of the most common examples of OCD is recurring obsessive thoughts about germs and dirt, with a compulsion to repeatedly "clean off the dirt". Other compulsions include repeated cleaning, obsessive on counting, arranging and organizing, especially putting things in a special order.

OCD is usually a persistent condition, and in Western countries, it is thought that about one to three out of 100 people have OCD. And it usually develops between the ages of 18 and 30.

So far, there is no large-scale epidemic investigation into OCD in China, apart from some studies by provinces and cities years ago, showing that less than 1 percent of the population suffers from OCD.