INFECTIONS - Medicine for Mountaineering and Other Wilderness Activities - page 309

humans by a tick bite or, in some areas, by lice. The ticks live on rodents and small an-
imals such as chipmunks, squirrels, and rabbits. About two to fifteen days after the bite,
chills,fever,severeheadache,muscleachesandpains,jointpains,acough,andoftennaus-
ea and vomiting appear. A red rash may appear on the body and limbs. Bleeding from the
nose, lungs, or gastrointestinal tract may occur but usually is not severe. The initial attack
lasts two to ten days and may be followed by an asymptomatic remission lasting three to
ten days. During the remission, fever is absent and the person feels well. A relapse, during
whichtheprevioussymptomsrecur,butinamilderform,usuallyappearsseventotendays
later in untreated individuals. In such individuals, three to ten relapses may occur before
complete recovery. Blood smears should be examined under a microscope during febrile
episodestoidentifytheorganism.Doxycyclineshouldbegiventoshortenthesymptomatic
period and prevent relapses.
More information is available at www.cdc.gov/ncidod/dvbid/RelapsingFever/in-
dex.htm .
Plague
Plague is a serious infection caused by Yersinia pestis , an organism transmitted to hu-
mans by contact with infected rodents or rabbits or by flea bites. The organism, not partic-
ularly widespread, is found chiefly in the southwestern United States and in rural areas of
South America, Africa, and Asia, particularly Vietnam. After multiplying in the skin fol-
lowing a bite, the organisms spread to regional lymph nodes and produce large swellings
(buboes), which are responsible for the name bubonic plague. Fortunately, involvement of
the lungs is rare; when pneumonia does occur, the infection is termed pneumonic rather
than bubonic, and becomes transmissible by droplets in the air. The illness is character-
ized by high fever, chills, prostration, and shock. It may be rapidly fatal, particularly in the
pneumonicform.Treatmentwithstreptomycinandtetracyclineshouldbestartedwhenever
the infection is even suspected and should be administered by a physician.
More information is available at www.cdc.gov/ncidod/diseases/submenus/
sub_plague.htm .
Tularemia
Anotherinfectiontransmittedtohumansfromwildrodentssuchasrabbitsandmuskrats
is tularemia. Humans acquire infection from skinning infected animals or by the bite
of ticks. A red swelling develops at the site of inoculation, then enlarges and ulcerates.
The fever, chills, headache, and nausea that accompany spread of the organism to the
bloodstream begin suddenly two to ten days after inoculation. An enlarged spleen, rashes,
and prostration may complicate severe cases. Treatment with tetracycline and gentamicin
should be given by a physician.