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The medications nifurtimox and benznidazole are effective treatments during the acute phase of Chagas disease. The efficacy of these drugs is much lower when the disease is in the chronic phase. Avoiding exposure to the pathogen through vector control is the most effective method of limiting this disease.

a) Micrograph of red blood cells with crescent-shaped cells outside. These parasitic cells are about the length of 2 red blood cells. B) photo of a triatomine bug.
(a) Trypanosoma cruzi protozoan in a blood smear from a patient with Chagas disease. (b) The triatomine bug (also known as the kissing bug or assassin bug) is the vector of Chagas disease. (credit a: modification of work by Centers for Disease Control and Prevention; credit b: modification of work by Erwin Huebner)
  • How do kissing bugs infect humans with Trypanosoma cruzi ?

Leishmaniasis

Although it is classified as an NTD, leishmaniasis is relatively widespread in tropical and subtropical regions, affecting people in more than 90 countries. It is caused by approximately 20 different species of Leishmania , protozoan parasites that are transmitted by sand fly vectors such as Phlebotomus spp. and Lutzomyia spp. Dogs, cats, sheep, horses, cattle rodents, and humans can all serve as reservoirs.

The Leishmania protozoan is phagocytosed by macrophages but uses virulence factors to avoid destruction within the phagolysosome. The virulence factors inhibit the phagolysosome enzymes that would otherwise destroy the parasite. The parasite reproduces within the macrophage, lyses it, and the progeny infect new macrophages (see Micro Connections: When Phagocytosis Fails ).

The three major clinical forms of leishmaniasis are cutaneous (oriental sore, Delhi boil, Aleppo boil), visceral (kala-azar, Dumdum fever), and mucosal (espundia). The most common form of disease is cutaneous leishmaniasis , which is characterized by the formation of sores at the site of the insect bite that may start out as papules or nodules before becoming large ulcers ( [link] ).

It may take visceral leishmaniasis months and sometimes years to develop, leading to enlargement of the lymph nodes, liver, spleen, and bone marrow. The damage to these body sites triggers fever, weight loss, and swelling of the spleen and liver. It also causes a decrease in the number of red blood cells (anemia), white blood cells (leukopenia), and platelets (thrombocytopenia), causing the patient to become immunocompromised and more susceptible to fatal infections of the lungs and gastrointestinal tract.

The mucosal form of leishmaniasis is one of the less common forms of the disease. It causes a lesion similar to the cutaneous form but mucosal leishmaniasis is associated with mucous membranes of the mouth, nares, or pharynx, and can be destructive and disfiguring. Mucosal leishmaniasis occurs less frequently when the original cutaneous (skin) infection is promptly treated.

Definitive diagnosis of leishmaniasis is made by visualizing organisms in Giemsa-stained smears, by isolating Leishmania protozoans in cultures, or by PCR-based assays of aspirates from infected tissues. Specific DNA probes or analysis of cultured parasites can help to distinguish Leishmania species that are causing simple cutaneous leishmaniasis from those capable of causing mucosal leishmaniasis.

Questions & Answers

what is haemaophilus influenzae
GALI Reply
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GALI
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Yunusa Reply
it act as hereditary material, coding for proteins and guide for life processes such as development reproduction etc
khan
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maryam Reply
differences between prokaryotes and eukaryotes
Taiwo Reply
Eukaryotic cells contain membrane-bound organelles, such as the nucleus, while prokaryotic cells do not.
Margo
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usman
margo calvi....its your simple difference
Sadiqur
likely objective questions
Naa
what is largest Organ in the body
Dr
Skin is the largest organ in the body
Yadav
heart is the largest organ of the body
usman
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maryam
liver is the largest organ in the body
maryam
skin
Janet
skin
Elyas
bilharzia
Elyas
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Elyas
liver is the largest organ in the body
maryam
Skin is the largest
Amin
skin
Amin
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Shahid Reply
thank u
Shahid
bacteriology encyclopedia
Mzafar
Who invented microbes?
manor Reply
Which year did Robert koch invented the microbes?
manor
Robert Koch
Matilda
Antony Van Leeuwenhoek invented microbes through a designed single lensed microscope.
Mohamed
what is microbiology
Nyoik Reply
microbiology is the study of micro organisms. this can be multicellular,unicellular & acellular
Janet
what is the difference between DNA/RNA
kanaaLka
DNA is a double stranded molecule while RNA is a single stranded molecule
Lovely
who is the inventor of microscope
Alberta
What are antibodies?
Happy Reply
they are immune cells that are released by immune system to fight strangers like microbes
Ahmed
a blood protien produce in response to an counteracting a specific antigen
Pooja
Why salmonella typhi is harmful protozoan?
Saily Reply
because make typhoid that is considered as a food born illness
Ahmed
Name any five modes of transmission.
Happy
what are the scientific names and common names of some microbes
Rich Reply
Staphylococcus aureus - staph Streptococcus pyogenes - strep Botulism - Clostridium botulinum Rocky Mountain spotted fever - Rickettsia rickettsii Diphtheria - Corynebacterium diphtheriae Gonorrhea - Neisseria gonorrhoeae
Tammy
what are the limitations of the Koch's postulate
Naa
how a microorganism growth.
Zubair Reply
Is foetus a parasite to his or her mother? if yes and if no ho
Mashauri Reply
y
Yusri
yes
Yashkin
yes
Zubair
yes it a parasite to the mother because it feeds on the mother for survival
Beatrice
yes
Redwan
no
Elasha
definition of a parasite: an organism that lives in or on an organism of ANOTHER species (its host) and benefits by deriving nutrients at the other's expense
Elasha
no because an organism can inky be a parasite if it causes harm to its HOST. And the fetus does not cause harm to its mother under normal conditions
aliyu
yes
Naa
what is biosensor in microbiology
Raja Reply
What are biosensor
Raja
what's are biosensor
Raja
what is microbiology defination
Rinku Reply
microbiology is the study of small or manuit organisms which cannot be seen with our nacked eyes unless with the aid of the microscope
Brandina
is the study of living organisms which are not directly visible to a direct eye but can only be seen under a microscope
Ipa
ok
Ipa
microbiology is the study of living organisms of microscopic size it is also the study of micro organisms with their form structure reproduction psychology metabolism and classification
Priyanka
ok
Aminu
Microbiology are the study of microorganisms either microscopic or sub microscopic creaters mainly unicellulars, multicellulars and subcellulars. Such as protozoa,bacteria and viruses.
Rana
it is the biological study of viruses, fungi, protozoa, bacteria which in collective name are called micro organisms, unlike microscopic organisms being invisible, that requires a magnifications with the help of a microscope.
Mohamed
is the branch of science that deals with the study of micro and microorganism and there life cicle
GALI
right...
Latif
what are the importances of Microbiology?
Erick Reply
don't know
SINGLE
we obtained the insulin from the bacteria. and some microorganisms are decomposer in ecosystems.
Zubair
nitrogen in the air is fixed into the soil by microbes example is nitrobactor
Matilda
yes
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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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