GASTROINTESTINAL DISORDERS - Medicine for Mountaineering and Other Wilderness Activities - page 274

devices have also been implicated. Diagnostic blood tests for this virus are widely avail-
able, but development of a vaccine has not yet been accomplished. Gamma globulin is of
no value for preventing infection.
Anotherformofnon-A,non-Bhepatitis—animportantformworldwide—ishepatitisE,
which is rarely encountered in the United States. The virus was first identified in 1989 and
has been linked to epidemics in Africa and Asia and to two outbreaks in Mexico. Infection
usually results from ingestion of water contaminated with sewage and can be prevented by
routine disinfection. Infection can also be spread by close personal contact. Like hepatitis
A, hepatitis E usually produces an acute infection that is rarely fatal and heals without pro-
ducingchronicliverdisease.However,insomeoutbreaksthemortalityinpregnantwomen
has been as high as 20 percent. No diagnostic blood test is available, but the virus can be
identified in stool samples. No vaccine is available. The effectiveness of gamma globulin
for preventing or ameliorating the infection is unknown.
Hepatitis F and G are recently discovered bloodborne infections about which little is
known.
The onset of hepatitis may be abrupt or insidious and follows an incubation period ran-
ging from three weeks to six months. The earliest symptoms are loss of appetite, general
malaise, and easy fatigability. Later a low fever and nausea and vomiting appear. Many
smokers have a peculiar loss of taste for cigarettes. In individuals with more severe infec-
tions, the symptoms increase in severity. Lightcolored stools and dark-colored urine may
precede the appearance of jaundice by several days. Vague upper abdominal discomfort
and tenderness may be present, particularly in the right upper quadrant, but severe pain is
absent. After the appearance of jaundice, some individuals experience ill-defined joint or
muscular pains. A highly variable skin rash may be present, and some have generalized
itching. When jaundice does develop, it often lasts three to six weeks. Malaise, easy fatig-
ability, and loss of appetite may persist for several more months.
No effective treatment for the acute episodes of any type of hepatitis infection is avail-
able.AstudyofpreviouslyhealthyyoungadultsintheU.S.Armyindicatedthatrestriction
of exercise had no effect on the course of the disease for that rather select group of indi-
viduals. Most wilderness explorers would fall into the same group of previously healthy,
relatively young adults. However, most people infected with hepatitis do not feel capable
of more than very mild exercise. A nourishing diet, high in proteins and carbohydrates and
supplemented with vitamins, should be provided.
All drug therapy should be avoided if possible, including alcohol and drugs to promote
sleep. The liver metabolizes most drugs. When that organ's function is impaired by hep-
atitis, such metabolism may be much slower than normal. If the drugs are not completely
metabolized between doses, they can accumulate in the blood and may reach toxic concen-
trations.