The fight against tuberculosis cases in the U.S. has stalled for the first time in more than 20 years, federal health officials reported Thursday.

According to the Centers for Disease Control and Prevention (CDC), instead of declining, the number of new cases of TB actually went up last year. This was the very first time since 1992 that the U.S. has seen an increase in new cases of TB. Although the overall increase of 157 additional cases is small, the officials said that it can be worrying whenever progress stalls.

"It's always concerning when we see progress stall - especially when there are proven interventions to prevent a disease," said Tom Frieden, the CDC director.

According to the report, there were a total of 9,563 TB cases in 2015. The majority of the cases, at 66.2 percent, occurred in foreign-born individuals living in the U.S. Asians had the highest rate at 28.2 cases per 100,000 people. There were 3,201 cases of TB in people born within the U.S. with an incidence rate of 1.2 cases per 100,000. In terms of regions, 4,839 TB cases were reported in four states: California, Florida, New York and Texas.

The CDC is not sure why TB cases have not continued to decline. The officials noted that reduced funding on a global scale could be affecting these rates, which is why new and improved preventive measures should be developed and enforced.

"We will need new and expanded efforts," CDC official Dr. Jonathan Mermin said.

The report added, "Resuming progress toward TB elimination in the United States will require intensification of efforts both in the United States and globally, including increasing U.S. efforts to detect and treat latent TB infection, strengthening systems to interrupt TB transmission in the United States and globally, accelerating reductions in TB globally, particularly in the countries of origin for most U.S. cases."

TB is a contagious bacterial disease that affects the lungs and can lead to dangerous health conditions, especially in people who have other diseases. In many cases TB can be latent, which means that people who are infected with the bacteria do not have any symptoms. The infection can be treated with antibiotics but some strains have been developing resistance, which makes treatment a lot more difficult. When left untreated, however, TB can lead to death.