Travel medicine and vaccines for HIV-infected travelers.

For the purposes of vaccination, persons with asymptomatic HIV infection and CD4+ cell counts of 200/μL to 500/μL are considered to have limited immune deficits and are generally candidates for immunization. HIVinfected persons with CD4+ cell counts less than 200/μL or history of an AIDS-defining illness should not receive live-attenuated viral or bacterial vaccines because of the risk of serious systemic disease and suboptimal response to vaccination. Available data indicate that immunization during antiretroviral therapy restores vaccine immunogenicity, improves the rate and persistence of immune responses, and reduces risk of vaccine-related adverse events, although vaccine responses often are suboptimal. Major issues for travelers to the developing world are vaccine-preventable illnesses (hepatitis A virus, yellow fever, and typhoid fever), traveler's diarrhea, and malaria. This article summarizes a presentation by D. Scott Smith, MD, at the IAS-USA continuing medical education program held in San Francisco in April 2012.