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236 CHAPTER 11

Source: Centers for Disease Control and Prevention (CDC) Source: Centers for Disease Control and Prevention (CDC)

FIGURE 11-11 Child’s right arm depicts the
FIGURE 11-12 Small, hard lump or lesion due to
characteristic spotted rash of Rocky Mountain
Rocky Mountain spotted fever, on hard palate of
spotted fever
child’s mouth
transmission of most of the diseases transmitted by tick
vectors. Initial signs and symptoms are similar to other humans, but most often are found in the hair, around the
tick-borne infections, including sudden onset of fever, ankles and in the genital area. Once embedded in the
headache, and muscle pain, followed by development host’s skin, ticks can cause a small, hard, itchy lump sur-
of a rash (Figure 11-11). This disease can be difficult rounded by a red ring or halo. Other than the red ring or
to diagnose in the early stages. In a small percentage of halo, the organism may cause signs or symptoms in any
cases, the bull’s eye rash fails to develop and the symp- area of the body (Figure 11-12). The longer an infected
toms and signs appear insignificant, but without quick tick stays attached to the skin, the greater the chances
and adequate treatment it can lead to death. grow for acquiring an infection by the host.
Despite effective treatment developed from ex- When the rickettsial organism enters through breaks
periences with treating the disease for at least the past in the skin including small wounds such as cuts or scrapes
75 years, Rocky Mountain spotted fever still is a serious on the hands, fingers, or other exposed areas of the body,
and potentially life-threatening infectious disease today. and even when going barefoot and perhaps stepping on
Up to 5 percent of those who contract Rocky Mountain an infected insect. But unlike some infective organisms
spotted fever will still die from the infection even with that reside only in a certain area of an insect vector’s body
the somewhat effective treatment available today. But such as in the saliva, bacteria that cause Rocky Mountain
dramatic progress has been made from the early days of spotted fever may circulate in all the fluids inside the tick
the documentation of the disease and effective antibiotic vector’s body. If the fluids are squeezed from or crushed
therapy has greatly reduced the number of deaths caused from an infected tick when personally removing it from
by Rocky Mountain spotted fever. In the years before the the body or from another person or a pet, an infection
development of two antibiotics called tetracycline and can occur if the fluid happens to come in direct contact
chloramphenicol in the late 1940s, perhaps as many with an area of broken skin. It is also possible to develop
as one-third of those infected who developed Rocky an infection when a mucous membrane or an eye is
Mountain spotted fever died. These figures are only esti- touched after coming in contact with the fluids from an
mates because mortality records at that time period were infected tick.
sketchy at best in some areas of the country.
RMSF can be contracted in two ways, most com- Babesiosis
monly through the tick bites or through infectious
organisms that enter the body through breaks in the skin. Babesiosis is the term for a somewhat rare infection of
Ticks can quickly and painlessly attach themselves to the the blood caused by a parasite that lives in some species
skin and proceed to feed on the blood of the host. They of ticks. The disease is caused by a malaria-like para-
can lodge anywhere on the bodies of animals, including sitic organism from the genus Babesia, an intracellular