A GAO report reveals that the high-security laboratories that study such deadly diseases as anthrax and plague lack national standards and strategy, putting the country at risk.

The facilities, known as high-containment laboratories, also are being built to local standards since there are no national guidelines for their design, construction and operations, the GAO said.

"The cost of building and maintaining high-containment laboratories, combined with the current lack of national standards and the uncertainty about the number of high-containment laboratories needed to address priorities, exposes the nation to risk," the report said. 

In one instance of lack of standards, the report said, a Centers for Disease Control and Prevention (CDC) high-containment lab in Atlanta had its power knocked out in 2007 by lightning. The outage shut down the air pressure system that kept dangerous pathogens from escaping.

The United States also has no reliable source for the number of such high-security labs, the GAO reported.

The GAO estimated that the total had risen to 1,495 in 2010 from 1,362 in 2008. It based the tally on numbers from the CDC and Agriculture Department's Federal Select Agent Program, but called it "an incomplete picture."