The number of TB cases in Los Angeles County dropped from a peak of 2,100 in 1992 to 706 cases in 2009, it was announced on Wednesday.

Most local cases appear to be contracted abroad, the Los Angeles County Department of Public Health (LACDPH) said.

Despite the drop, Los Angeles remains a major hub of international travel and immigration, making it particularly susceptible to new cases of the disease, the department said.

Tuberculosis is not a thing of the past, but affects millions of people across the globe every year, said the department.

In a statement marking World TB Day 2010, LACDPH director Jonathan Fielding said drug-resistant forms of the disease -- MDR- TB (multidrug-resistant tuberculosis) and XDR-TB (extensively drug- resistant tuberculosis) -- still present serious health problems.

"Though efforts to manage, treat and eliminate tuberculosis have met with remarkable success in Los Angeles County, we are not immune to more serious forms of this disease," Fielding said.

"There were 116 local cases of MDR-TB between 1998 and 2008, which reminds us that TB is an ongoing threat," he said. "Through rapid diagnostic methods, timely reporting of cases to Public Health and appropriate care for all individuals, we can work toward one day eradicating this disease and its stronger forms."

Worldwide, more than 9 million cases of tuberculosis are reported every year, and more than 1.5 million people die of TB annually, according to statistics provided by the department.