After two straight months of declines, the index that measures inflation at the wholesale level surged by an unexpected 0.8% in January, though analysts said the likelihood of inflation becoming a problem is slim, given the current downturn.

The U.S. Labor Department said Thursday that producer prices jumped last month as increases in oil and energy prices led to higher costs for manufacturers. The rise -- which represents the biggest increase the index has seen in six months -- was slightly more than what economists were looking for, as they expected producer prices to rise 0.3% for the month.

The results follow two months of declines in the index. In December, the producer price index fell by 1.9% and in November, by 2.5%.The Labor Department’s “core” reading on wholesale inflation, which strips out volatile food and energy costs, showed that prices rose 0.4% during the month -- much more than the 0.1% that economists were looking for.

Still, analysts rejected concerns that inflation will become a full-blown problem.

“The increase in the core PPI was firmer than expected, but we are likely to see considerably softer readings in the months ahead. That is because aggregate demand is weak, intermediate goods prices have fallen sharply, and capacity utilization in the manufacturing sector is at a postwar low,” JPMorgan analyst Abiel Reinhart wrote in a note.

The core PPI results could also reflect the fact that many firms increase prices at the start of a new calendar year, analyst Ian Lyngen of RBS Greenwich Capital wrote in a note.

Producer prices are watched by Wall Street as a measure of both corporate profitability and the possible specter of consumer-based inflation, which is tracked in the consumer price index. Factories that experience rising costs for supplies can pass off their prices to consumers, or can absorb those costs and experience lower profitability -- but often passing off costs during a recession is difficult for many businesses.

The rise in wholesale inflation rose in several categories, including energy, business equipment and telecommunications. Energy prices rose 3.7% during the month, while wholesale gasoline prices rose 15%. Food prices were down 0.4%.

The threat of inflation has been kept mostly in check by the recession, which officially began in December 2007, and Federal Reserve Chief Ben Bernanke said he believes the risk of full-blown inflation is minimal. At a speech Wednesday in front of the National Press Club, Bernanke said the central bank would begin to conduct longer-ranging inflation projections -- a move that could lay the groundwork for the eventual adoption of a formal inflation objective.

Bernanke said the Fed’s drastic interest rate cuts and the current economic environment were unlikely to fan inflation pressures, arguing that any potential onset of inflation could be thwarted once the economy and markets begin to recover.