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Diagnosis of schistosomiasis is made by the microscopic observation of eggs in feces or urine, intestine or bladder tissue specimens, or serologic tests. The drug praziquantel is effective for the treatment of all schistosome infections. Improving wastewater management and educating at-risk populations to limit exposure to contaminated water can help control the spread of the disease.

Cercarial dermatitis

The cercaria of some species of Schistosoma can only transform into adult worms and complete their life cycle in animal hosts such as migratory birds and mammals. The cercaria of these worms are still capable of penetrating human skin, but they are unable to establish a productive infection in human tissue. Still, the presence of the cercaria in small blood vessels triggers an immune response, resulting in itchy raised bumps called cercarial dermatitis (also known as swimmer’s itch or clam digger's itch). Although it is uncomfortable, cercarial dermatitis is typically self-limiting and rarely serious. Antihistamines and antipruritics can be used to limit inflammation and itching, respectively.

  • How do schistosome infections in humans occur?

Common eukaryotic pathogens of the human circulatory system

Protozoan and helminthic infections are prevalent in the developing world. A few of the more important parasitic infections are summarized in [link] .

Table titled: Parasitic Diseases of the Circulatory and Lymphatic Systems. Columns: Disease, Pathogen, Signs and Symptoms, Transmission, Diagnostic Tests, Antimicrobial Drugs, Protozoa. Babesiosis; Babesia spp.; Malaise, chills, fever, headache, myalgia, arthralgia; From animals to humans via Ixodes tick vectors; Blood smear, serology, IFA, and PCR; Atovaquone and azithromycin or clindamycin and quinine. Chagas disease ; Trypanosoma cruzi; Fever, headache, body aches, swollen lymph nodes; potentially fatal; Between humans or from animal reservoirs via triatomine (kissing bug) vector; Blood smear, IFA, EIA, PCR, xenodiagnoses; Nifurtimox, benznidazole. Leishmaniasis Leishmania spp.; Ulcer; enlargement of the lymph nodes, liver, spleen, and other organs; Between humans or from animal reservoirs via sand fly (Phlebotomus spp., Lutzomyia spp.) vectors; Blood smear, culture, PCR, DNA probe, biopsy; Stibogluconate, amphotericin B, miltefosine. Malaria; Plasmodium vivax, P. malariae, P. falciparum, P. ovale, P. knowlesi; Extreme fever, chills, myalgia, nausea, and vomiting, possibly leading to organ failure and death; Between humans via Anopheles mosquito vectors; Blood smear, EIA; Chloroquine, atovaquone, artemether, and lumefantrine. Toxoplasmosis Toxoplasma gondii; Tissue cysts; in pregnant women, birth defects or miscarriage; Contact with feces of infected cat; eating contaminated vegetables or undercooked meat of infected animal; Serological tests, direct detection of pathogen in tissue sections; Sulfadiazine, pyrimethamine, spiramycin; Helminths. Schistosomiasis; Schistosoma spp.; Rash, fever, chills, myalgia; chronic inflammation and scarring of liver, spleen, and other organs where cysts develop; Snail hosts release cercaria into freshwater; cercaria burrow into skin of swimmers and bathers; Eggs in stool or urine, tissue biopsy, serological testing; Praziquantel..

Resolution

Despite continued antibiotic treatment and the removal of the venous catheter, Barbara’s condition further declined. She began to show signs of shock and her blood pressure dropped to 77/50 mmHg. Anti-inflammatory drugs and drotrecogin-α were administered to combat sepsis . However, by the seventh day of hospitalization, Barbara experienced hepatic and renal failure and died.

Staphylococcus aureus most likely formed a biofilm on the surface of Barbara’s catheter. From there, the bacteria were chronically shed into her circulation and produced the initial clinical symptoms. The chemotherapeutic therapies failed in large part because of the drug-resistant MRSA isolate. Virulence factors like leukocidin and hemolysins also interfered with her immune response. Barbara’s ultimate decline may have been a consequence of the production of enterotoxin s and toxic shock syndrome toxin (TSST) , which can initiate toxic shock.

Venous catheters are common life-saving interventions for many patients requiring long-term administration of medication or fluids. However, they are also common sites of bloodstream infections. The World Health Organization estimates that there are up to 80,000 catheter-related bloodstream infection s each year in the US, resulting in about 20,000 deaths. World Health Organization. “Patient Safety, Preventing Bloodstream Infections From Central Line Venous Catheters.” 2016. http://www.who.int/patientsafety/implementation/bsi/en/. Accessed July 29, 2016.

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Key concepts and summary

  • Malaria is a protozoan parasite that remains an important cause of death primarily in the tropics. Several species in the genus Plasmodium are responsible for malaria and all are transmitted by Anopheles mosquitoes. Plasmodium infects and destroys human red blood cells, leading to organ damage, anemia, blood vessel necrosis, and death. Malaria can be treated with various antimalarial drugs and prevented through vector control.
  • Toxoplasmosis is a widespread protozoal infection that can cause serious infections in the immunocompromised and in developing fetuses. Domestic cats are the definitive host.
  • Babesiosis is a generally asymptomatic infection of red blood cells that can causes malaria-like symptoms in elderly, immunocompromised, or asplenic patients.
  • Chagas disease is a tropical disease transmitted by triatomine bugs. The trypanosome infects heart, neural tissues, monocytes, and phagocytes, often remaining latent for many years before causing serious and sometimes fatal damage to the digestive system and heart.
  • Leishmaniasis is caused by the protozoan Leishmania and is transmitted by sand flies. Symptoms are generally mild, but serious cases may cause organ damage, anemia, and loss of immune competence.
  • Schistosomiasis is caused by a fluke transmitted by snails. The fluke moves throughout the body in the blood stream and chronically infects various tissues, leading to organ damage.

Fill in the blank

The ________ mosquito is the biological vector for malaria.

Anopheles

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The kissing bug is the biological vector for ________.

Chagas disease

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Cercarial dermatitis is also known as ________.

swimmer’s itch

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Short answer

Describe main cause of Plasmodium falciparum infection symptoms.

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Why should pregnant women avoid cleaning their cat’s litter box or do so with protective gloves?

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Questions & Answers

what are ways of handling sharps
namugenyi Reply
never recap or bend a sharp objects
benita
describe the process of platelet formation
Joy Reply
what is parasitic helminths
Sadiya Reply
list three categories of symbiotic relationships.
mary Reply
what's the difference between microbial intoxication and infectious diseases
dranimva Reply
microbial intoxication results when a person ingests a toxin or a poisonous substance that has been produced by a microbe while infectious disease results when a pathogen colonize the body and subsequently cause disease.
mary
weighing balance is needed in lab of microbiology for weighing?
amna Reply
It is mainly used for media preparation and product testing purpose.
Nakaweesi
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nuur
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Shamsuddeen Reply
study of living organisms that are too small to be visible with naked eye
Marah
yes
Ahmed
microbiology is the study of microscopic organisms, either unicellular(single cell), multicellular( cell colony), or acellular (lacking cell).
munachimso
is the word Atypical or a typical bacteria. .am confused pliz help
MUWANGUZI Reply
typical bacteria
Zulpha
okay thank you what does that mean
MUWANGUZI
atypical means that it has some characters from bacteria not all characters ...but tybical means that it has all the characters that bacteria have
Reham
thank you Zulpha
MUWANGUZI
some examples please
MUWANGUZI
thank you Reham
MUWANGUZI
1) typical bacteria contain a cell wall whereas atypical bacteria usually do not contain a cell . 2) typical bacteria can be either Gram-positive or Gram-negative while atypical bacteria remain colorless with Gram staining. 3) cells of typical bacteria are large ,while cells of the atypical small
Marah
Example of atypical : Mycoplasma pneumoniae , chlamydophila pneumoniae , legionella
Marah
what is micro biology
Jauharah Reply
is the study of organisms which can't be viewed by our necked eyes
Egumat
Because it preexisting causing secondary infection after collateral damage of normal microbota
Rafaa Reply
combinations of drugs that can't be taken together and why
Grace Reply
Antagonism: the combined action is less than that of the more effective agent when used alone). All these effects may be observed in vitro (particularly in terms of bactericidal rate) and in vivo والله اعلم
Lenovo
....fermentros have 1-15litre capacity
AMAR Reply
which of the following microorganisms are classified as eukaryotic?
Semugab Reply
how do I see the list?
Melissa
what are the choices?
Melissa
dear tell us the choices
MUWANGUZI
mr semugab give us the list please
Nambi
Fungi
munachimso
what are the new discoveries of microorganisms
Ezibon Reply
bacteriology,viriology,micrology
Egumat
understanding of contributed to attempts to treat contain disease
james Reply

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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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