Final answer:
A laboratory worker who is exposed to potentially infectious materials may request a vaccine for hepatitis B, as this is a common occupational hazard in healthcare settings and a vaccine is readily available.
Step-by-step explanation:
A laboratory worker exposed to potentially infectious materials on the job may request a vaccine for hepatitis B. The Hepatitis B vaccine is recommended because it is known to be a common occupational hazard for health-care workers and a vaccine is available for prevention. Hepatitis B was once a leading on-the-job hazard, and vaccination has been recommended by the CDC since 1982, significantly reducing rates of infection among healthcare workers. Even though vaccination is now common, it is not always effective and not all individuals are vaccinated. Therefore, there is still a small risk for infection, especially for health-care workers working with individuals who have chronic HBV. It is important to note that while there is a vaccine for hepatitis B, there are no vaccines available for HIV or syphilis, and the need for a brucellosis vaccine would be uncommon and highly specific to particular laboratory settings.