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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

okay. Go ahead and ask
Blessing Reply
Industrial microbiology mcq
mohamed
Okay. What's your question?
Blessing
life arises from living matter or live organism.
Swami Reply
yes
sildra
I think live matter arises from non living matter
sildra
I dont think so...can u explain with an example
Manya
living maters made by non living matters
sildra
non living matters like stones? rocks?
Manya
eno
sildra
no
sildra
then?
Manya
cells are made by C N O minerals etc
sildra
I mentioned these as non living maters
sildra
that's all
sildra
cells are made up of those things but they originate from living things..
Manya
ok
sildra
Ok..good chat:-)
Manya
where are you from
sildra
thanks
sildra
India...u?
Manya
Tamil nadu
sildra
I am from Maharashtra
Manya
what about your studies
sildra
completed bsc.. preparing for msc entrance...wbu?
Manya
same
sildra
are you microbiologist
sildra
yes i am
Manya
good
sildra
what s the scope for micro in ur state?
Manya
did you find your college to higher studies
sildra
have to give an entrance exam for every college here...so lets c
Manya
food industries, medical lab, vaccine industries ,etc
sildra
hoping for pune University...wbu?
Manya
great!
Manya
is that centeral University right
sildra
what is your namr
sildra
hello
Udhaya
Hi
Maruf
Family kindly help me with this question? 1) Shortlist the configurative measurements of the following human anatomical ranges of÷ - Blood ( haemeglobin) in both male and female - Haematocytes in both male and female - Hepatocytes in both male and female - Lymphocyte / T. Lymphocytes in both male
Gifted
My names are Gift Mwale and am a Zambian. Kindly help me with this research which goes like this... 1) Shortlist the configurative measurements of the following human anatomical ranges of ÷ - Blood ( haemeglobin) in both male and female - Hepatocytes in both male and female - Haematocytes in both
Gifted
please what is the full meaning for TCDS
UDEME
from a single cell
Freedom
tcds means transcranial direct current stimulation...in this small electric currents are given to brain( specific parts) to help increase brain performance or to help with depression.. current should be in range 0.5-2.0mA
Manya
please can anybody talk about brain tumour and its cure.
BELLO Reply
enlargement of the thyroid gland resulting in over production of hormone.
Kamal Reply
What can u say on Thyroid Cancer?
Abdulkareem
Please, talk about the thyroid cancer.
BELLO
explain the Grave's disease
John Reply
what is cell
Avi Reply
is unit of life
Kamaluddeen
Ok
mohamed
who is an industrial microbiologist
Cynthia Reply
I want to know the biochemical composition of bacteria
Josh Reply
It contains peptidoglcon, DNA nd RNA
Asiya
bacteriophage disadvantage
Momina Reply
disease due to __________ abnormalities are termed primary immunodeficiencies
Tayee Reply
Some primary immunodeficiencies are due to a defect of a single cellular or humoral component of the immune system.
Prince
Examples of primary immunodeficiencies include: chronic granulomatous disease, X-linked agammaglobulinemia, selective IgA deficiency etc
Prince
thank you
Nana
explain microbial mutation
Emerald
what is mutation
Cynthia Reply
alteration in genetic makeup
UDEME
Hi, I'm new here. I'm Bello Abdul Hakeem from Nigeria.
BELLO Reply
welcome on board
Kamaluddeen
Thanks brother I'm an undergraduate. I hope to study for MBBS.
BELLO
pls guys help me out
Linda
what is limitation of plate
Linda
limitation of plate load test . there are some that should be considered while performing load test which are given below, this test is usually performed on relatively similar plate ,usually 1 or 2 square foot area the reason is that the plate of greater are the economically not feasible
yemi
iam new here my name shafiu umar from Nigeria
Shafiu
thanks shafiu
gambo
how to differentiate Gram positive from Gram negative bacteria?
Faheem
by the cell membrane
Tim
with gram staining which has 4 steps
Freedom
Mechanism of bacterial pathogenicity
rashida Reply
Toxicity
Ibrahim
write a short note on Algea
najaatu Reply
green minutes plants organisms that are produced in turf.
Prince
Algae is a kind of a photosynthetic organism, which is usually grown in the moist areas. These are usually the simple plants that grow near to the water bodies. It contains a kind of chlorophyll pigments that act as a primary coloring agent.
Avi
they are eukaryotic and most lived in fresh water. they are photosynthetic that's, they contain chlorophyll and store starch in discrete chloroplast.
Prince
are bacteria important to man
just Reply
yes, depending on the type of bacteria .eg the normal florals, the latic acid batteries etc are important to man
Lois
I mean latic acid bacterial
Lois

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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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