Suffering from sinusitis or/and sore throat? the pollution and infected particles in the air could be the cause.. Make yourself a mouth/nose mask as shown in the picture. Where to get a piece of the filter cloth? I shall be happy to send it to you. Send me a self-addressed stamped (Rs 10 stamp) envelop at: Mr Maheshwari S-164 Greater Kailash Part 1. New Delhi 110048.