GASTROINTESTINAL DISORDERS - Medicine for Mountaineering and Other Wilderness Activities - page 260

and use a handdisinfectant gel after any contact with an infected person. All feces and
vomitus should be buried where contamination of water does not occur, preferably after
being mixed with an antiseptic such as 1 percent Cresol. All utensils and other instruments
shouldbeimmersedinboilingwater.Indispensableitems,suchasclothingorsleepingbags
that cannot be boiled, should be aired in bright sunlight for at least one or two days after
the individual is recovering.
Invasive Bacterial Infections (Dysentery)
Invasive bacterial infections, or bacillary dysentery, are caused by a wide variety of
bacteria including Salmonella , Shigella , Campylobacter , Yersinia , Aeromonas , Clostridi-
um , non-cholera Vibrios , and occasionally other organisms. These organisms are found in
temperate as well as tropical areas, but severe cases of bacillary dysentery occur most fre-
quently in tropical or semitropical climates.
Salmonellae are particularly widespread. Virtually all domestic animals, including
household pets—dogs, cats, birds, and turtles—and many wild animals harbor these bac-
teria. The number of asymptomatic human carriers has been estimated at two persons per
thousand.
Contaminated water and food spread infections. Any item of food or drink can be
contaminated. For Salmonella the greatest single source of human disease is poultry
products—both meat and eggs—and raw meat of other types. Lack of hydrochloric acid in
the stomach (the result of disease or therapy for peptic ulcer) and alteration by antibiotics
of the normal microbial flora in the intestinal tract increases susceptibility to infection by
these organisms.
The incubation period varies from one to six days with an average of forty-eight hours
(somewhat shorter for Salmonella ). The onset is often rather abrupt and characterized by
severe, intermittent abdominal cramps followed by diarrhea that may be copious and soon
progresses to watery, foul stools. The stools contain large amounts of mucus and pus and
occasionally moderate amounts of blood, particularly four to five hours after the onset.
Nausea is common, but vomiting may not occur. Infection usually is associated with fever
(100.5°Fto102°F,38°Cto39°C,orhigher)andchillyfeelingsorfrank,shakingchills.Ab-
dominal tenderness may be pronounced, is most marked in the lower portion of the abdo-
men, and is frequently accompanied by spasm of the abdominal muscles. Abdominal pain
may be sufficiently intense, localized, and associated with enough rebound tenderness to
suggest an acute abdominal disorder requiring surgery. The individual is obviously ill and
may be prostrate.
Aftersixtoeighthoursthesymptomsabatesomewhat,butthediseasemaytakesevento
ten days to run its course. Considerable variation in the severity of symptoms is observed,
even among persons infected at the same meal.