WTI crude oil prices continue to climb higher for a fifth consecutive day early on Thursday, supported by an unexpected decline in US crude inventories even as markets cheer the development of vaccines against COVID-19. At the time of writing, WTI crude oil is trading at around $45.84 per barrel.

Over the previous session, WTI crude oil had gained around 1.8% of its value after the EIA report revealed a surprising drawdown in crude stockpiles in the US. According to the EIA, crude inventories in the US fell by 754k barrels over the past week, against economists’ forecast for a 127k barrel build instead.

Crude oil has been trading bullish in the past few sessions ever since pharmaceutical companies have announced the development of highly effective vaccines to fight the coronavirus pandemic. So far this week, US oil has gained around 9% over optimism that the rollout of the vaccine could spur economic recovery around the world and boost oil demand.

However, analysts have cautioned that the optimism could get tempered down as the rollout of the vaccines could take several months and its impact could take even longer. Fresh infections continue to rise across the US and many parts of the world, which raise the possibility of imposition of more lockdowns and restrictions that could further weaken oil demand.