IMMUNIZATIONS - Medicine for Mountaineering and Other Wilderness Activities - page 55

fourtoeightweeks,withathirddosesixtotwelvemonthsafterthesecond.Ifthreedosesof
IPVcannot beadministered within therecommended intervals beforeprotection isneeded,
alternative schedules are available at www.cdc.gov/travel/#hepa . A single booster dose for
adult travelers provides lifelong immunity.
Rabies
Rabies, a form of viral encephalitis, is essentially always fatal if clinical signs of infec-
tion appear. Postexposure treatment with wound cleansing, immune globulin, and vaccina-
tion successfully prevents clinical infection when properly administered.
Preexposure vaccination for rabies has long been recommended by ACIP for anyone
traveling to a rabies endemic area (essentially all of South and Central America, Africa,
and most of Asia) for more than thirty days. However, that recommendation has recently
been modified to include visitors, such as travelers to remote areas, forwhom access to ap-
propriate medical care, including immune globulin and vaccine, would require more than
twenty-four hours. In addition, vaccination is recommended for children, particularly for
preverbal children and children so young they cannot report or might be afraid to report
contact with a potentially infected dog or other animal.
Intramuscular vaccination is now exclusively recommended. (Intradermal vaccination
with human diploid cell vaccine [HDCV] was approved by the FDA in 1987 but does not
produce antibody titers as high as those produced by intramuscular vaccination, and anti-
bodytiters donot persist as long. The question ofintradermal versus intramuscular vaccin-
ation is currently moot in the United States because intradermal HDCV, the only product
licensed for intradermal vaccination, is not available.)
Possibly a more compelling reason for rabies preexposure immunization is the world-
wide shortage of rabies immune globulin. Cleansing the wound, administration of immune
globulin, and administration of vaccine are considered equally essential, and rabies deaths
have resulted from omission of any of them. Only approximately one-third of the immune
globulinneededforpostexposuretherapyworldwideiscurrentlybeingproduced.Indevel-
oping countries, most individuals exposed to rabies are not given immune globulin unless
they knew enough about postexposure rabies therapy to demand its administration. Stud-
ies have clearly demonstrated that most travelers think rabies is not a problem and have no
knowledge of postexposure therapy.
Individuals who have been previously immunized do not need postexposure immune
globulin. Vaccination on day zero and day three after exposure is all that is required.
However, those vaccinations are considered essential. (Any bite or scratch by a dog or any
otheranimalinarabiesendemicareamustbeconsideredarabiesexposure,andpostexpos-
ure therapy must be instituted regardless of the vaccination status of the animal. Vaccines
used to vaccinate animals in areas where rabies is endemic are not as reliable as those used