Oil prices continued their steep decline on Thursday, with U.S. West Texas Intermediate crude falling more than 5% at the low to $45.88 per barrel — a price not seen since Jan. 2019 — as fears of the coronavirus outbreak, and what it could mean for crude demand, continue to batter prices.

"Current forecasts of crude oil demand have fallen off a cliff. As China is the largest consumer in the world, the unclear impact of the coronavirus is driving WTI lower and lower," KKM Financial founder and CEO Jeff Kilburg said to CNBC. "As China is the largest consumer in the world, the unclear impact of the Corona virus is driving WTI lower and lower," he added.

After falling more than 5% in early trading, U.S. West Texas Intermediate pared some of its losses to settle 3.37%, or $1.64, lower, a level not seen since Jan. 2019. WTI posted its fifth straight session of losses, and tumbled even deeper into bear market territory, currently sitting 29% below its 52-week intraday high level of $66.60, reached last April.

International benchmark Brent crude fell to $50.97 per barrel, its lowest level since Dec. 2018, before paring some of the losses to settle 2.34% lower at $52.18 per barrel.

As the number of coronavirus cases outside of China rises, GRZ Energy founder Anthony Grisanti said it remains to be seen how much crude demand will be impacted. "Demand for oil was weak before all this started because of the China trade war, and I would expect this to continue," he said Thursday on CNBC's "The Exchange." "There's nothing in the horizon that says this is going to improve anytime soon."