29. Epidemiology and prevention of enteric helminth and protozoon infections
Enteric helminth and protozoa infections
- Pinworms
- Giardia
- Amebiasis
- Ascariasis
- Tapeworms
- Whipworm
Pinworms
- Parasite: Enterobius Vermicularis
- Epidemiology
- Outbreaks common in schools
- Transmission
- Faecal-oral
- Clinical features
- Key symptom: itching at the rectum
- Parasites leaves the anus at night, leaves eggs around the anus
- Diagnosis
- Put tape at the anus, look for eggs in the morning
- Treatment:
- Vermox
- Antiminth
Giardiasis
- Parasite: Giardia lamblia
- Epidemiology
- Very common water-borne infection
- Transmission
- Faecal-oral transmission
- Lives in the upper GI tract
- Clinical feaatures
- Diarrhoea
- Abdominal pain
- Flatus
- Steatorrhea
- Diagnosis
- Microscopy of stool to look for cysts
Amebiasis
- Protozoa: Entamoeba histolytica
- Epidemiology
- Found in 4% of the population
- Transmission
- Faecal-oral
- Invades the mucosa of coecum and ascending colon
- Clinical features
- Can be asymptomatic
- Diarrhoea
- Abdominal pain
- Flatus
- Can travel to liver, causing hepatitis
Ascariasis
- Helminth: Ascaris lumbricoides (the large intestine round worm)
- Epidemiology
- The most common helminth infection worldwide
- Mostly affects children in developing and tropical countries
- Transmission
- Transmitted by contaminated food
- Penetrate the intestine, invades liver, lung, heart
- Symptoms
- Can be asymptomatic
- Invasion of lungs -> causes Loeffler syndrome
Tapeworms
- Helminth: Taenia solium
- In raw or undercooked pork or beef
- Can be 25 meters in length
- Cysticercosis -> cysts of larvae in any organ, especially in the brain
Whipworm
- Helminth: Trichuris trichiura
- Epidemiology
- Very common parasitic infection in the US
- Transmission
- Faecal-oral transmission
- Worm lives in coecum and appendix
- Female produces thousands of eggs every day
- Clinical features
- Often asymptomatic
- Allergic reactions
- Anaemia
- Diarrhoea