This specimen is a tissue imprint from a liver biopsy performed on a 35 year old female patient recently migrated from India. She suffers from recurrent fever and feelings of lethargy. Small pale patches of skin are apparent on parts of her body. Blood smears have revealed no evidence of malaria.

1) Identify the parasite indicated on the field (genus and species)

Leishmania donovani
(2 marks)
2) Name the stage of the parasite shown on the field

amastigote
(1 mark)
3) What is the name of the clinical disease caused by this infection ?

Kala azar
(1 mark)
4) What is the vector of this parasite (genus only)

Phlebotomus sp.
(1 mark)

The specimen provided is a thin film of blood taken from a 75 year-old war veteran who served time during the second world war in New Guinea and Borneo. He now lives in a small town just west of Mackay, where he enjoys a reasonably independent life. He reports having periods of feeling "a bit crook every now and then" (fevers and chills) and remembers being treated for malaria when he returned home from service, but was not followed up for treatment. He normally does not seek medical advice during these ill periods. He has not left Australia since the war.

1) Identify the parasite indicated (genus only)

Plasmodium sp.
(1 mark)
2) Identify the stage of the parasite shown on the field

Trophozoite
(1 mark)
3) What is the definitive host of this parasite

Mosquito (Anopheles sp.)
(1 mark)
4) Is it likely that he contracted the infection in Australia? Discuss.

Although outbreaks have occurred, malaria is not considered to be endemic to Australia. It is more likely that he contracted the disease whilst overseas.

(2 marks)

The specimen provided is a faecal sample from a community health nurse, stricken with acute diarrhoea. The patient had recently returned from a trip to a station in far north Queensland. He described conditions at the station as "squalid" and made a report to his supervisors, detailing the lack of proper sanitation.

1) Identify the parasite indicated (genus, species and stage)

Entamoeba histolytica cyst
(3 marks)
2) Describe how this parasite is transmitted

Faecal-oral route
(1 mark)
3) Detail which criteria you used to make your diagnosis

>= 10µm, <=4 nuclei
(1 mark)

The specimen provided is of a bronchial aspirate taken from a patient suffering from a debilitating pneumonia. The patient was diagnosed as HIV positive some three years ago and is starting to show signs of AIDS related syndromes, such as Kaposi's sarcoma, and a chronic infection of Cryptosporidium.

1) Identify the parasite indicated (genus, species and stage)

Pneumocystis carinii "cysts"
(3 marks)
2) Could the appearance of this organism be related to the patient's HIV status ?

Yes, as it may cause disease in immunocompromised hosts
(1 marks)
3) Does this parasite pose a risk to health workers handling the specimen ?

Not really, as long as adequate safety procedures are followed. This organism is usually only a danger to the immunocompromised.
(1 mark)