Occurrence
AIDS and HIV infection occur worldwide. The Joint United Nations Programme on HIV/AIDS estimates that, as of the end of 2005, nearly 40 million persons were living with HIV/AIDS worldwide. Although the most globally affected part of the world remains sub-Saharan Africa, in recent years, the steepest increases in HIV infection have occurred in Eastern Europe, Northern, Central, and East Asia (see map 4-5). Many countries lack comprehensive surveillance systems, and despite improvements, the true number of cases is likely greater than officially reported, particularly in developing countries. Because HIV infection and AIDS are distributed globally, the risk for international travelers is determined less by geographic destination and more by behaviors that put them at risk for becoming infected, such as sexual (1) and drug-using behaviors (2).
Prevention
No vaccine is available to prevent infection with HIV. For information on the safety of vaccines for HIV-infected persons see Chapter 9. Travelers should be advised that HIV infection is preventable. HIV can be transmitted through sexual intercourse and needle- or syringe-sharing; by medical use of blood, blood components, or organ or tissue transplantation; through artificial insemination; and perinatally from an infected woman to her infant. HIV is not transmitted through casual contact; air, food, or water routes; contact with inanimate objects; or by mosquitoes or other arthropod vectors. The use of any public conveyance (e.g., an airplane, an automobile, a boat, a bus, or a train) by persons with AIDS or HIV infection does not pose a risk of infection for the crew members or other travelers.
Travelers should be advised that they are at risk if they—
- Have sexual contact (heterosexual or homosexual) with an infected person.
- Use or allow the use of contaminated, unsterilized syringes or needles for any injections or other procedures that pierce the skin, including acupuncture, use of illicit drugs, steroid or vitamin injections, medical or dental procedures, ear or body piercing, or tattooing.
- Use infected blood, blood components, or clotting factor concentrates. HIV infection by this route is rare in countries or cities where donated blood and plasma are screened for antibodies to HIV.
Travelers should be advised to avoid sexual encounters with persons who are infected with HIV or whose HIV infection status is unknown. Travelers should also be advised to avoid sexual activity with persons who are at high risk for HIV infection, such as intravenous drug users, commercial sex workers (both male and female), and other persons with multiple sexual partners. In countries with high rates of HIV infection, many persons without these risk factors may be infected and be unaware of their status. Condoms, when used consistently and correctly, prevent transmission of HIV. Travelers who engage in vaginal, anal, or oral-genital sexual contact with a person who is HIV-infected or whose HIV status is unknown should use a latex condom. Persons who are sensitive to latex should use condoms made of polyurethane or other synthetic materials. Some areas may have a limited supply and selection of condoms, or available condoms may be of inferior quality. Persons traveling to these areas who engage in sexual contact with persons who are HIV-infected or whose HIV status is unknown should carry their own supply of condoms. When a male condom cannot be used properly, a female condom should be considered. When no condom is available, travelers should abstain from anal, vaginal, and oral-genital sexual contact with persons who are HIV-infected or whose HIV status is unknown. Barrier methods other than condoms have not been shown to be effective in the prevention of HIV transmission. Spermicides alone have also not been shown to be effective, and the widely used spermicide nonoxynol-9 can increase the risk of HIV transmission. In many countries, needle-sharing by intravenous drug users is a major means of HIV transmission and transmission of other infections, such as hepatitis B and hepatitis C. Travelers should be advised not to use drugs intravenously or share needles for any purpose (3). Travelers should also be advised to avoid, if at all possible, receiving medications from multidose vials, which may have become contaminated by used needles.
In many developed countries (e.g., Australia, Canada, Japan, New Zealand, western European nations, United States), the risk of transfusion-associated HIV infection has been virtually eliminated through required testing of all donated blood for antibody to HIV. In the United States, donations of blood and plasma must be screened for HIV-1 and HIV-2 antibodies, the HIV-1 p24 antigen, and traces of HIV genetic material that may indicate infection. Developing countries may have no formal program for testing blood or biological products for contamination with HIV. In those countries, travelers should (when medically prudent) avoid use of unscreened blood-clotting factor concentrates or concentrates of uncertain purity. If transfusion is necessary, the blood should be tested, if at all possible, for HIV antibody by appropriately trained laboratory technicians using a reliable test.
Needles used to draw blood or administer injections should be sterile, single use, disposable, and prepackaged in a sealed container. Travelers with insulin-dependent diabetes, hemophilia, or other conditions that necessitate routine or frequent injections should be advised to carry a supply of syringes, needles, and disinfectant swabs (e.g., alcohol wipes) sufficient to last their entire stay abroad. Before traveling, such persons should consider requesting documentation of the medical necessity for traveling with these items (e.g., a doctor’s letter) in case their need is questioned by inspection personnel at ports of entry.
Occasionally, an overseas traveler’s duties may involve the need to handle blood products (e.g., nurse volunteer drawing blood or medical missionary performing surgeries) or other potentially infectious materials (e.g., research scientist preparing human tissue samples). Persons who may have contact with HIV-infected biological materials should ensure that they will have access to all appropriate personal protective equipment necessary (e.g., latex gloves, goggles, face shield, gowns) and that this equipment meets established international quality standards. Such affected travelers may also wish to consider familiarizing themselves with the principles of postexposure prophylaxis and, in the event of a high-risk exposure were to occur, establishing a plan for seeking medical consultation and bringing a supply of antiretroviral medication of sufficient quantity to provide postexposure prophylaxis until medical care can be obtained (4). Efficacy of postexposure prophylaxis with antiretrovirals for nonoccupational exposures to HIV (e.g., sexual, injecting drug use) has not been established. CDC recommends it be considered as an unproven clinical intervention after careful consideration of potential risks and benefits and with full awareness of gaps in current knowledge (5).
International travelers should be advised that some countries screen incoming travelers for HIV infection and may deny entry to persons with AIDS and evidence of HIV infection. These countries usually screen only persons planning extended visits, such as for work or study. Persons intending to visit a country for an extended stay should be informed of that country’s policies and requirements. This information is usually available from the consular officials of the individual nations. An unofficial list compiled by the U.S. Department of State can be found at the following URL: http://travel.state.gov/travel/tips/brochures/brochures_1230.html.
