Life cycle Cryptosporidium spp.

Question 1

What species of Cryptosporidium cause human infection?

Answer 1

C. Hominis

C. Parvum

Question 2

What is the classification of Cryptosporidium spp?

Answer 2

Intracellular protozoan in the category sporozoan

Question 3

How is cryptosporidium spp. transmitted?

Answer 3

Thick walled oocysts that are sporulated exit the host through feces that contaminate water and food

Question 4

What are the steps of the cryptosporidium lifecycle outside of the human host?

Answer 4

1. Sporulated oocyst containing 4 sporozoites are excreted by an infected host through the feces. The oocyst is protected by a thick, hardened cell and can remain infectious for 6-8 months in optimal circumstances outside the body. They are resistant to heat, cold and chlorine based disinfectants like pool water
2. Transmission of crypto sporium through injection of by feces contaminated food or water or direct contact with infected animal or human

Question 5

What are the lifecycle steps of cryptosporidium lifecycle in the human host?

Answer 5

1. Ingestion by a suitable host. Most genome types are host specific but humans are not specified by a certain genome. C. parvum can infect humans, kettle, sheep, goats, horses, pigs and mice.
2. Excystation of oocysts happens and sporozoites escape from the cyst and are released into the epithelial cells of the GI tract are attacked.
3. Asexual multiplication takes place by merogony or sysogomy
4. Sexual multiplication takes place and microgamonts (male) and macrogamonts (female) are produced. Both types grow and the microgamonts are released and land on macrogamonts and fertilize them and a zygote is produced.
5. Zygote give rise to 2 different types of oocysts a thick and a thin wall oocyst. The thick walled are excreted into the environment and the thin walled stay and are involved in the internal alto infective cycle.
6. The thick wall is excreted by the host and the cycle starts anew

Question 6

What type of life cycle has cryptosporidium spp?

Answer 6

Direct life cycle where the human is the definitive host

Question 7

What are the symptoms of cryptosporidium spp. infection?

Answer 7

Some are asymptomatic

But common symptoms are Watery diarrhea, stomach cramps or pain, dehydration, nausea, vomiting, fever, weight loss the infection is self-limiting but not to immunocompromised people. These can develop serious chronic and sometimes fatal illness.

Question 8

What is the incubation time for cryptosporidium spp. infection?

Answer 8

2-10 days after infection

Question 9

Where is cryptosporidium spp. endemic?

Answer 9

Worldwide but the highest rates are found in developing countries

Question 10

How is cryptosporidium spp. diagnosed?

Answer 10

PCR on feces samples.

Other possible tests are: examination of stool samples using a modified acid-fast stain using microscopy or enzyme immunoassays for detection of antigens.

Question 11

How is cryptosporidium spp. diagnosed?

Answer 11

PCR on feces samples.

Other possible tests are: examination of stool samples using a modified acid-fast stain using microscopy or enzyme immunoassays for detection of antigens.