New Delhi, Aug 13 - Masks are only for those infected with influenza A (H1N1), those showing symptoms of the disease or those handling patients, the central government warned Thursday and said it was 'unscientific for normal people' to wear them.

'It is unscientific for normal people to wear masks,' Director General of Health Services (DGHS) R.K. Srivastava told reporters here as the government stepped in to prevent panic buying of masks that had created a shortage in the market.

India has reported 20 deaths from the deadly virus that has infected 1,193 people. Of these, 589 have been discharged after treatment.

'We have 1.1 billion population and if everyday one person uses two masks the demand would not be met. No industry, organisation or government could fulfil this demand,' Srivastava told reporters.

'We want to inform everyone about who all should use these masks and where to use them. The mask is necessary for the swine flu patients and those who are taking care of them. Besides this, the masks are for those who are handling the patients, at labs, collecting samples and diagnostic centres,' he added.

He said that those who have been advised home quarantine and have mild symptoms of swine flu are also required to use masks.