Experts convened by the CDC have produced guidelines that reinforce a common-sense approach to biosafety in day-to-day laboratory activities.
A supplement to Morbidity and Mortality Weekly Report, January 6, “Guidelines for Safe Work Practices in Human and Animal Medical Diagnostic Laboratories”  address safe work practices in human and animal diagnostic laboratory, including microbiology, chemistry, hematology, and pathology with autopsy and necropsy guidance.
The US Bureau of Labor Statistics estimates that there are approximately 500,000 human and animal diagnostic lab workers, and that “any of these workers who have chronic medical conditions or receive immunosuppressive therapy would be at increased risk for a laboratory-acquired infection (LAI) after a laboratory exposure.” But post exposure infection risks are unknown because of the difficulty in determining the source or mode of transmission and non national surveillance system is available.
Bacteria account for more than 40% of laboratory-acquired infection (LAI), with more than 37 species “as etiologic agents,” says the report, but other microbes also present risks. For example, “Hepatitis B has been the most frequent laboratory-acquired viral infection, with a rate of 3.5–4.6 cases per 1000 workers, which is two to four times that of the general population,” according to the report. “Any laboratorian who collects or handles tubes of blood is vulnerable,” it adds.
Also, LAI surveys have found that laboratory staff “were three to nine times more likely than the general population to become infected with Mycobacterium tuberculosis.”