c. Relapsing Fever.
(1) General. Relapsing fever is an acute infectious disease caused by
several species of spirochetes, and the main reservoir is rodents. In March 1968, boy
scouts camped near Spokane, Washington, in an old rodent-infested cabin and
subsequently experienced the relapsing fever. This incident was the largest outbreak of
tick-borne relapsing fever in the Western Hemisphere.
(2) Signs and symptoms. This fever causes the victim to abruptly
experience fever 3 to 10 days after infection when there are large numbers of
organisms present in the blood and in perhaps other body fluids. The victim suffers
tachycardia, vomiting, arthralgia, severe headache, and often delirium. The fever
subsides but after an afebrile period of 3 to 10 days, there is a second attack of fever
and fewer organisms in the blood. These febrile attacks sometimes recur 3 to 10 times
and in the case of epidemics, mortality can be as high as 50 percent but is generally low
(0-5 percent).
(3) Treatment. The administration of procaine penicillin G, tetracycline, or
erythromycin has proven effective.
d. Tick Paralysis. Tick paralysis was first attributable to ticks in Australia in
1843 when sheep and calves became paralyzed; however, a case was reported in
Oregon when a child's motor and sensory nerves were affected. The child was unable
to stand in the morning after retiring in good health, and on the third day was unable to
swallow or speak. After two fully engorged ticks from the occipital region were
removed, the child recovered within a week. Death is usually caused by respiratory
failure. In the early stages, tick paralysis is painless and not much fever which is in
contrast to poliomyelitis. Characteristically, a person experiences muscle weakness,
lack of coordination, and ascending flaccid paralysis. Usually, these symptoms
disappear once the tick is removed. Treatment of tick paralysis is symptomatic.
Oxygen and respiratory assistance may be needed.
Section III. LOUSE-BORNE DISEASES
1-6.
GENERAL
There are three species of lice which are of medical importance. These are the
body louse, the head louse, and the crab louse. Lice are most commonly found in
temperate and subarctic areas where people wear heavy clothing in several layers.
When the body lice aren't feeding on a person's body, they remain in his clothing. Body
lice are the primary vectors of disease which includes typhus fever and relapsing fever.
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