(2) Reservoirs. The reservoirs are usually infected persons, dogs, cats,
jackals, and gerbils. Most cases, in the absence of destructive complications, heal
spontaneously and afford immunity against further infection.
b. Mucocutaneous Leishmaniasis. Chronic infections with L. braziliensis can
also result in invasion of cartilage tissue. This form of the disease is known as
mucocutaneous leishmaniasis. In severe infections, this may result in extensive
destruction of these tissues, especially the cartilage of the nose, lips, and ears.
c. Visceral Leishmaniasis (KaIa Azar).
(1) Signs/symptoms. This form of the disease is a chronic, systemic infection
characterized by fever, enlargement of the spleen -and liver, lymphatic involvement,
anemia, progressive emaciation, and weakness.
-- ATTENTION --
Untreated, the disease is highly fatal.
(2) Location. This disease occurs primarily in rural areas of most tropical and
subtropical regions throughout the world. The epidemiology is similar to cutaneous
Ieishmaniasis, except that the infectious agent is Leishmania donovani.
(3) Immunity. Recovery confers immunity; however, the cutaneous and
visceral forms of the disease do not confer cross immunity.
(4) Control measures. There is no vaccine for artificial immunization;
therefore, control measures are based upon protection from and destruction of
5-32. AFRICAN TRYPANOSOMIASIS (AFRICAN SLEEPING SICKNESS)
African trypanosomiasis, also known as African sleeping sickness is a
severe, highly fatal disease caused by infection with the flagellate
protozoan Trypanosoma brucei gambiense or T. b. rhodesiense,
transmitted through the bite of the tsetse fly (Glossina sp.). The
disease is confined to tropical Africa, where the tsetse fly thrives.
a. Reservoirs. The primary reservoir for T. b. gambiense is man. The reservoir
of the disease is a person with tryanosomes in his blood stream. Individuals may be
asymptomatic carriers of the disease and clinical symptoms may be delayed 2 to 5
years. Wild game, especially antelope and bushbuck, and domestic cattle are also
important animal reservoirs of T. b. rhodesiense.
b. Signs/Symptoms. In the early stages, the disease is characterized by fever,
intense headache, insomnia, lymph node enlargement, anemia, edema, and rash.
Later symptoms include wasting, drowsiness, and central nervous system signs.