Twentyfive per cent were suffering from PTSD, he said, with symptoms including stress, nightmares, trouble sleeping and worrying about a recurrence of the disaster.

Doctors have prescribed them sleeping pills, he said.

Seven per cent are suffering from depression and have become suicidal. They have been prescribed antidepressants and their relatives have been asked to keep a close watch on them, Prat said.

He said these patients had a history of accumulated stress and so could not cope with the prolonged flooding.

The ministry will continue monitoring the floodhit residents for mental health problems - including suicidal thoughts, PTSD, depression and alcoholism - for the next three months, which is the period it would take most people to readjust their lives, he said.

About 10,000 booklets on relaxation methods will be distributed among the residents and a hotline (1323) will be kept open round the clock to advise on mental health problems, he added.

As for the main focus of the ministry's rehabilitation plan - to prevent epidemics such as leptospirosis, dengue fever, severe diarrhoea and hepatitis - Prat said officials had worked hard on tasks including sanitation, pest control and improving water quality.

He reported that the ministry had dispatched 4,800 medical mobile units, which had so far treated 670,453 people for waterborne diseases. Nearly half the patients suffered from handfootandmouth disease, while rashes and flu were the next most common ailments.

Prat said there were 80,912 patients with mental health problems, of which 870 were given medication, 1,525 were given a family consultation and 290 were hospitalised as they had previous mental illnesses.