Watchdogs are urging people to be on the lookout for conmen posing on doorsteps as NHS Scotland staff.Others have scammed householders with offers of fake anti-virus sprays for their gardens.Police say attempts to defraud people have risen by 10 per cent during the corona lockdown.Some con merchants are going door to door pretending to be NHS workers collecting donations towards a vaccine or offering to shop for money.Other scams include cold-calling residents offering to spray paths and driveways with an anti-bacterial treatment.A spokesperson for Trading Standards in East Lothian said: “You are not being rude if you shut the door on unsolicited callers.“NHS staff will not turn up unannounced and ask you for donations.“If someone that you