The sharp spike in fuel prices could threaten the travel industry's recovery, experts say. They note that recent increases in oil prices have prompted airlines to boost fares. "We have already seen four upticks in the price of airfare just in the last month and a half, so I say buy your airfares now," travel writer Pauline Frommer said. "If oil goes higher, there is no way the cost of tickets isn't going to skyrocket." Nevertheless, some observers are starting to see a significant rebound in demand for international travel, and they attribute the trend to "pent-up demand."