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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 ?


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

how psychrophiles live at such a low temperature that their proteins dont get denatured
Harsh Reply
anti freeze proteins are synthesized to prevent such denaturations..
okay thank u
can you suggest me a book for food microbiology
and for industrial microbiology
food microbiology by M.R Adam and M.O.Moss
Industrial microbiology by L.E.casida.
maam can you suggest a best book that have applied microbiology concepts
mem can you suggest a best book of microscopy
for applied microbiology K.R.Aneja and other book by Allen Laskin
for microscopy Kirsteen Roger.
Define sterilization
Pramod Reply
Sterilization refers to any process that removes, kills, or deactivates all forms of life and other biological agents like prions present in a specific surface, object or fluid, for example food or biological culture media.
sterilization is the process of making an aseptic condition or microbe free environment to keep the objects from any kind of contamination.
Cool. I work for a Sterilisation company in India. We do Gamma Radiation, Steam Sterilisation and Ethylene Oxide Sterilisation
Explain the polymerization reaction of DNA polymerase enzyme?
Swetha Reply
I think in my opinion polymerization means monomers connects and produce large molecular chain
DNA polymerase I catalyzes the polymerization of dNTPs into DNA. This occurs by the addition of a dNTP (as dNMP) to the 3' end of a DNA chain, hence chain growth occurs in a 5' to 3' direction.Thus in this reaction, a phosphoanhydride bond in the dNTP is broken, and a phosphodiester is formed.
Thank you
ok..Thank you
Nicely explained
Welcome 🙏
write a note of microbiology with definition
Lucky Reply
Microbiology is the study of all living organisms that are too small to be visible with the naked eye. This includes bacteria, archaea, viruses, fungi, prions, protozoa and algae, collectively known as 'microbes'.
write down the difference branches of microbiology
Baccteriolog: the study of bactera. Immunology: the study of the immune system. It looks at the relationships between pathogens such as bacteria and viruses and their hosts. Mycology: the study of fungi, such as yeasts and molds. Nematology:the study of nematodes (roundworms).
Bacteriology: the study of bacteria. Immunology: the study of the immune system. It looks at the relationships between pathogens such as bacteria and viruses and their hosts. Mycology: the study of fungi, such as yeasts and molds. Nematology: the study of nematodes (roundworms).
Parasitology :the study of parasites. Phycology: the study of algae. Protozoology : the study of protozoa, single-celled organisms like amoebae. Virology:the study of viruses.
Parasitology: the study of parasites. Not all parasites are microorganisms, but many are. Protozoa and bacteria can be parasitic; the study of bacterial parasites is usually categorized as part of bacteriology. Phycology: the study of algae. Protozoology: the study of protozoa, single-celled organis
Virology: the study of viruses.
difference between gram negative and gram positive bacteria.
the difference between gram negative and gram positive bacteria is the colour which is obtained after staining techniques.. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with.
Father of paleobotany?
The father of paleobotany is Birbal Sahni...
It is the study and recovery of ancient plants and geological contents
Father of immunology
Louis pasture was really father of immunology,despite Edward jenner poineering by introducing the vaccine against smallpox.
thank you anna
define a cell?
thank you Kaviya
Cells have many parts, each with a different function. Some of these parts, called organelles, are specialized structures that perform certain tasks within the cell.
cell is the basic structural and functional unit of life.
In biology, a cell ([sɛl], ”plural: cells”) is defined as the structural, functional, and biological unit of all organisms. It is an autonomous self-replicating unit that may exist as a functional independent unit of life (as in the case of a unicellular organism), or as a sub-unit in a multicellula
thank you
all bacterial cells have
Millie Reply
refamycin kills bacterial cell by acting on ...?
Yogesh Reply
monensin kills bacterial cell by acting on
genetic linkage cross over ratio ?
what is microbiology?
onuoha Reply
Hi!!! wants to know the meaning of microbiology
Christian Reply
Microbiology, study of microorganisms, or microbes, a diverse group of generally minute, simple life-forms that include bacteria, archaea, algae, fungi, protozoa, and viruses. The field is concerned with the structure, function, and classification of such organisms .
to study the life of microorganisms or microbes by knowing their characteristics types and relative species in lab
Microbiology is simply the study of microbial world.
Microbiology is the branch of biology in which we study microorganisms those which cannot be seen with naked eye these are bacteria,fungi,viruses Protozoa etc.
thanks for that information
microbiology, is a study of microorganisms adiversegroup of generally, simple life,
Thanks ever so much for the discussion.
Can anyone help with Organic Chemistry, and types?
which topic in organic chemistry
Introduction to organic chemistry.
Organic chemistry is the chemistry of carbon, an element that forms strong chemical bonds to other carbon atoms as well as to many other elements like hydrogen, oxygen, nitrogen, and the halogens. ... Many are composed of only carbon and hydrogen, collectively called hydrocarbons.
microbiology is the study of microorganisms like (bacteria ,viruses,fungi,protozoa and algae) their relationship to environment and their impact on environment .
can one tell me what are reservoirs and their types with explanation.
structure of protists
Rayyanu Reply
what is enzyme engineering
swati Reply
what is the difference between prokaryotes and eukaryotes?
Guirlaine Reply
Prokaryotes lack nucleus in their cells while eukaryotes have well defined nucleus in their cells
Prokaryotes are organisms that consist of a single prokaryotic cell. Eukaryotic cells are found in plants, animals, fungi, and protists. They range from 10–100 μm in diameter, and their DNA is contained within a membrane-bound nucleus. Eukaryotes are organisms containing eukaryotic cells.
The Day Jimmy"s Boa Ate the Wash by TRINKA HAKES NOBLE pictures by STEVEN KELLOGG
Alexia Reply
cytoplasmic membrane system in eukaryotes is called
Myerlyn Reply
I study in French,but I guess it's the same: we call it as the procaryotes "cytoplasme" but it's structure "cytosquelette" hope I helped.
hi bennini , I studied in English but I want to pursue in French .could u plz help me with French .thanks in advance
hi Si Yo, yes,of course how can I help you?
here can I download it where I could study it with relax dear
meaning of contagium vivum?
Royce Reply
explain transglutaminase cycle ?
Dilsath Reply

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