Emirates and Etihad airlines will tighten screening for passengers flying to Australia this week after the country imposed new requirements for enhanced explosives detection, the UAE companies said yesterday.Australia on Friday announced it would increase screening of passenger baggage on flights from Dubai and Abu Dhabi in the United Arab Emirates, as well as Doha, Qatar. While the directive stops short of the sweeping electronics ban introduced last month by the United States and Britain, it may include targeted screening of passengers' personal electronic devices.Emirates and Etihad Airways, two of the largest airlines in the Middle East, said the measures would take effect on Thursday.