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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

is it better to study microbiology and then medicine it makes no difference to go directly to medicine?
Jessee Reply
Dray's mathdme cell wall konse color k hote he
Jinal Reply
what is dray's mathdme cell wall
Prabhat
I confused. please help me
Karen
just confused
Raj
l don't understand it please explain it for me.
Karen Reply
epitopes are present on the surface of
Rohit Reply
at the tip of variable region on the antibody...where antigen and antibody binding sites combine...
Fiza
The term that is used refer to moving microbes under a microscope are referred to as?
Lee Reply
Members of the genus Neisseria cause which of the folowing human diseases?
Farah Reply
genital infections
Kamaluddeen
gonorrhoea
sandip
gonorrhoea
Jessee
4. Which of the following specimens should not be refrigerated? a. Urine b. Urogenital swab
Zahraa Reply
urine
Muuse
urine
Agatha
Urine
Tean
urine
Yasser
Urine
Ebtehal
urine
anamika
urine
Puja
urine
Inemesit
urine
Samuel
Urine
Muhammad
Details about McConkey agar
Muhammad
urine
SK
urine
what is bacteria
anamika Reply
a member of large number of unicellular microorganism which have cell wall but lack of cell organelles an oranised nucleus including somewhat can cause disease
Sukhdeep
Bacteria are usually composed of one cell onl to that are neither plants nor animals, microscopic, that may cause diseases or may be beneficial(in gut)... it depends upon their weapons. Nearly all animal life is dependent on Bacteria for their survival
Fiza
thanks
anamika
what factor make bacteria colony large and how could we sterlise it in large scale
fatty
nutrient concentration temp gaseous conc ph ion or salt concentration mositure condition factors contribute to make large colony. by autoclaving we will sterilize bactetia
Sukhdeep
Colony is actually visible growth of Bacteria that is as a result of suitable environment for growth i.e optimal conditions for growth, temperature, moisture etc. there're many methods to get rid of bacteria. If We stop giving them optimal conditions for living Bacteria will die soon .
Fiza
what's the difference between an antigen and a pathogen?
Pathogens are organisms that cause disease in other organisms whereas Antigen is a part of a pathogen that triggers the immune response..
Rajat
so it is the antigen that dendritic cells present to the T cells and not the pathogen itself?
no no antigen are the west product or part of the pathogen. in such case bacteria it self fight with over immune response & in another case bacteria release antigens
vasava
& other antigen like pollan grain, dust particles etc.....
vasava
pathogen are microbes that can infect the body and causw illness....antigens are the part of pathogens that alert the body to an infection
Sukhdeep
antigen is a part of blood and pathogen is foreign particle which causes diseases
Yogyata
antigen could be non microorganism.... where as pathogen is mixroorganism
tadesse
Thanks
Karen
a pathogen is a disease causing organism while an antigen is a protein in the white blood cells which combats pathogens.
Jessee
what type of widal test
sobhit Reply
this test determine for typhoid in this test if H,O antigen are present that indicate the positive test bac. are salmonella typhy
vasava
what h.o denotes
Iqra
o: body of bacteria, h: flagellate
Explain Mould
Chinenye Reply
Explain mycoses and it's classification
Chinenye
why do we have hiccups?
Manisha Reply
shakey diaphragm
Curlisse
The antibody binding site is formed primarily by:
Asalla Reply
How many types of MICROORGANISMS do we have?
Hope Reply
Hello friends
Hope
microorganisms are divided into seven type Bacteria archaea protozoa algae fungi virus and multicellular animal parasites
Raj
What's pathogenesity
Usman Reply
something that causes disease
Anietie
who is the father of microbiology?
Hope
antonie van leeuwenhoek
vasava
it is the severity of the effects caused by a pathogen
Jessee

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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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