A person aged 36 years is having firm belief that his wife is having affair. He often sits alone, muttering himself and hears voices commenting about him. He was absolutely normal 2 weeks before. Most likely diagnosis is

The patient has paranoid delusion & hallucination, 2 out of 5 symptoms are present. But the complaints are from post 2 weeks. Hence, the diagnosis is Acute Psychosis not Schizophrenia (according to ICD - 10) symptoms should be present for atleast 1 month).