Parasitic Infections

Front 1

Protozoa

Back 1

- Multicellular non-photosynthetic organisms.
- Live off other bacteria and show characteristic features (i.e. flagella, cilia etc)
- Asexually reproduce
- May live inside cells
- Partial immunity develops, but rarely excluded fully.

Front 2

Helminth

Back 2

- Worms
- Unicellular Organisms
- Do not replicate
- Build up in the body

Front 3

Schistosomiasis

Back 3

- Schistosoma Species
- Africa, S.America and China
- Lays eggs in messenteric veins
- Eggs ppt inflammation
- Burst vessel
- Travel to portal vein
- Enter liver
- Cause granuloma
- Fibrous tissue formation
- Occlusion of HPV leads to...
- Hepatosplenomegaly

Transmission: Water Snails

Front 4

Filariasis

Back 4

Two forms: Onchocerciasis and Lymphatic Filariasis

Onchocerciasis
- Lesions under skin
- Female lays eggs
- Eggs travel in the blood
- Reach the eye
- causes destruction
- River blindness

Transmission: Black Fly
Found: West Africa and S. America

Lymphatic Filariasis:
- Elephantiasis
- Adult worms live in the afferent lymph nodes
- lay eggs (microfilarae) which spread in the blood stream
- Acute: lymphadenitis
- Chronic: recurrent infection. Leads to lymphodoema of breast, scrotum, limbs since worms block the afferent lymph nodes.

Transmission: Mosquitoes
Found: West Africa, S. America

Front 5

Malaria

Back 5

Two forms: Tertian, Quartan

- Infection of erythrocytes
- Leads to abnormal cell cycle
- Bursting RBCs release TNF-A
- This damages tissues and causes symptoms
- Releases more eggs and microbes
- Taken up by the mosquito.

Symptoms:
- Headache
- Nausea and Vomiting
- Hypoglycaemia
- Feverish Convulsions (48 in tertian/72 in quartan)

Cerebral Malaria:
- Caused by P.Falciparum
- Adheres to microcapillaries
- Localised inflammation, hypoxia
- Comatosed (rarely brain damage)

Protection is conferred by certain Haematological conditions (Sickle Cell, thalassaemia)

Found: Africa
Transmission: Biting Female Mosquitoes

Front 6

Toxoplasmosis

Back 6

- Causes largely unnoticed symptoms: Sore throat, headache, lymphadenitis (in cervical lymph nodes mainly)

Transmission: Cysts in Cat faeces, uncooked meat and across the placenta

- Cysts remain inactive
- Preferentially muscle and neural tissue infection.
- May be re-activated in immune compromised individuals (i.e. those with HIV infection)
Accounts for around 30% of deaths of AIDS patients.
- Recurrent retinochoroiditis can lead to severe blindness
- Transmission across the placenta leads to congenital birth defects.
Organism: Toxoplasma Gondii