Oil prices fell to their lowest in seven weeks on Thursday on concerns that the spread of a newly identified respiratory virus from China may lower fuel demand at the same time a report showed oil inventories in the United States rose last week.We estimate a price shock of up to $5 (a barrel) if the crisis develops into a SARS style epidemic based on historical oil price movements,” JPM Commodities Research said in a note.The U.S. bank maintained its forecasts for Brent to average $67 a barrel in the first quarter and $64.50 a barrel throughout 2020.Brent crude futures .were down $1.05, or 1.7%, to $62.16 a barrel by 0125 GMT, and earlier dropped to the lowest since Dec. 4, after falling 2.1% the previous session.