of 17 /17
Cryptosporidium parvum Benjamin Harris

Cryptosporidium parvum Benjamin Harris. Cousins, Grandpa, Sisters

Embed Size (px)

Text of Cryptosporidium parvum Benjamin Harris. Cousins, Grandpa, Sisters


Cryptosporidium parvumBenjamin Harris1Cousins, Grandpa, Sisters


EpidemiologyFound on all six continents.

Distributed through fecal-oral route from infected hosts.

Most commonly transmitted through contaminated water.HostsDefinitive Host: non-specific (terrestrial mammals)

Intermediate Host: None

Infects:HumansLivestockPetsAlmost any domesticated mammal.First confirmed human case was 3-year-old girl from rural Tennessee in 1976LifecycleSporulated oocyst (containing four sporozoites) are ingested or inhaled by infected host.Excystation occurs and sporozoites are released attaching to intestinal or respiratory walls.Undergo asexual multiplication (schizogony or merogony) or sexual multiplication (gametogony).

Lifecycle ContinuedSexual multiplication yields:Microgamonts (male)Macrogamonts (female)

Upon fertilization of zygote, two types of oocysts can be produced.Thick-walled (typically excreated)Thin-walled (primarily for autoinfection)

TransmissionFecally contaminated food and waterSwimming pools, public drinking water, lakes, rivers.Animal-person (zoonotic)Approximately 50% of calves discrete oocysts.Person-PersonHigh frequency in day-care centers, bathrooms, urban.Fecal-oral route.Small contamination required:Infective dose (132 oocysts for healthy persons)

SymptomsNauseaVomitingAbdominal CrampsLow-grade feverFrequent watery diarrhea

Much more severe in all respects for immunocompromised persons (HIV/AIDS). CD4