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80 CHAPTER 4

Treatment and Prevention subcutaneous tissues in the mucocutaneous forms of the
organism. Most often other organs, and in particular the
Although babesiosis is most often self-limiting in hu- liver, are greatly affected by the visceral form.
mans, treatment may be necessary to alleviate some of From the historical vantage point, it is easiest to
the symptoms by eliminating the parasite. Prevention consider the Old World forms first. Old World cutaneous
of the disease is most effective when the tick vectors are leishmaniasis, known as oriental sore, is a disease that
controlled in endemic areas by destruction of the habi- has been known for hundreds of years if not longer, and
tats of ticks and the use of protective clothing. Insect there are descriptions of the conspicuous lesions formed
repellents help to avoid bites from ticks when properly on tablets in the library of King Ashurbanipal from the
used and body examinations to remove embedded ticks seventh century, some of which are thought to have
after exposure to ticks will greatly diminish the number been derived from earlier texts from 1500 to 2500 BC
of cases of babesiosis. (Cox, 2002). Detailed descriptions of oriental sores by
Arab physicians in the tenth century described what
was (and is) called Balkh sore from northern Afghani-
LEISHMANIASIS (OLD WORLD stan (Figure 4-3). Later records from various places in
CUTANEOUS LEISHMANIASIS) the Middle East including Baghdad and Jericho indicate
many of the conditions known by local names by which
Leishmaniasis is caused by several species of the genus they are still known today (Cox, 2002).
Leishmania called hemoflagellates and is transmitted by Old World visceral leishmaniasis, or kala-azar, also
sand flies, which are often prevalent in desert areas. The called black fever, is manifested by fevers and by an en-
disease occurs in various forms in both the Old and New larged spleen, a condition known as splenomegaly. The
World (the Americas). Upon infection, the parasites infect visceral type may be caused by Leishmania donovani,
and multiply in macrophages and are ingested by sand L. chagasi, or L. infantum. Cases of cutaneous Leishma-
flies when they feed on an infected person. In the gut of nia have been found in Texas and across the Mexican
the sand fly, the parasites multiply and reach the mouth- border in the past few decades, and it is believed that
parts of the insect from which the infective forms are in- L. meicana may be harbored by armadillos. This disease
jected into a new host when the sand fly again feeds upon is often confused with other diseases, especially malaria,
a potential victim (Figure 4-2). The disease leishmaniasis which is also endemic in the region where leishmaniasis
has a number of forms that range from simple cutane- is found. Kala-azar was first noticed in Jessore in India
ous ulcers to a substantial destruction of cutaneous and in 1824, where numbers of patients were suffering from
fevers. Although it was at first thought to be due to
malaria, the disease failed to respond to quinine,

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

FIGURE 4-2 Sand fly or biting midge, Cullicoides furens FIGURE 4-3 Left arm with a leishmanial lesion