LOS ANGELES, Oct. 2 (Xinhua) -- As the outbreak of H1N1, also known as swine flu, is spreading, U.S. laboratories could see a big surge in their testing workload this fall, the American Society for Clinical Pathology (ASCP) warned on Friday.

    This would lead to delays in tests for other diseases, potentially putting some patients at risk, the society said.

    A large spike in swine flu screenings could clog a lab system already struggling with a shortage of workers, the ASCP said.

    Citing federal statistics, the ASCP said that 138,000 new laboratory professionals will be needed nationwide by 2012, but fewer than 50,000 will be trained.

    California and other Far West states are weathering a 53 percent shortage of medical technologists in hospitals, commercial labs and other diagnostic facilities; followed by 46 percent in Arkansas, Louisiana, Oklahoma and Texas, and 42 percent in the Northeast.

    The shortage drew concerns from several laboratory professionals affiliated with the ASCP.

    "There are now thousands of different tests that doctors can order," said Dr. Michael Laposata, chief of pathology at Vanderbilt University Hospital in Nashville. "The whole issue of sheer workload and labor shortage is playing out in a big way with this H1N1 virus."

    Much of the concern among lab directors owes to the fact that since at least the 1990s, fewer people are choosing lab work as a career. Even if they do, fewer training programs are around to serve students, experts said.

    There are several tests for H1N1, the virus that causes swine flu. They range from rapid influenza diagnostic tests, which can detect influenza viral nucleoprotein antigen in as little as 30 minutes, to more sophisticated polymerase chain reaction assays. All require lab personnel to administer and review results, Laposata said.