Week 7 Quiz- A Traveller's Tale

What are the four Malaria Parasites? Malaria is a ……… organism (5) Plasmodium falciparum P. vivax P. ovale P. malariae Malaria is an intracellular parasite

Man is the only host for Entamoeba histolytica. This presents as diarrhoea with…… (1) Amoebic dystentery- mucus and blood in the stool Trophozoites also in stool

What are two differential diagnoses for multiple petechial haemorrhages throughout the white matter of the brain, on autopsy? (2) Cerebral Malaria Fat embolism

What is the difference between a definitive and intermediate hosts? (1) Definitive Host- host in which parasite reaches maturity and if applicable reproduces sexually Intermediate host- host in which the parasite only resides for a short period of time, in an immature form

Name four reasons for Malnutrition in underdeveloped countries. (2) War Famine: Crop failure (single staple) Low socioeconomic Absent breastfeeding, or prolonged exclusive breastfeeding Infections that increase requirement: giardia, TB, HIV etc.

Name the BIG 6 diseases, that cause premature death in developing countries (6) Acute Respiratory infection TB- increasing due to drug resistance and HIV Diarrhoeal disease Malaria HIV- some reversal of success achieved through public health Measles

You are working in Africa, and begin to realise the drugs you are giving your Malaria infected patients do not seem to be working. What could be going on? (2) The drug is not genuine- fake/counterfeit The drug is expired The drug was not actually taken by the patient/given by the nurse The drug wasn’t absorbed Drug resistance

A patient comes to see you for some travel advise. What do you need to know before you can give them any advise? (4) Patient factors: pre-existing health conditions, medications, allergies, reasons for travel Mode of travel Destination BUT ALSO planned itinerary: rural vs capital city, camping vs five star, volunteering with animals/refuges vs shopping

What are the 5 components of Disseminated intravascular coagulation (DIC) ? (5) Exposure of blood to procoagulants Formation of fibrin in the circulation Fibrinolysis Depletion of clotting factors End-organ damage

Fever plays an important role in our body’s defences against infection. What are some of the benefits of a fever? (5) Activates T-cell production Increases effectiveness of some IFN Limits the replication of some viruses/ bacteria Increases phagocytosis Increased Ig production

Name four of the organisms responsible for Travellers Diarrhoea? (2) Shigella Campylobacter Ecoli Salmonella

Name 5 of the Diseases, covered by Australia's National Immunisation Schedule (5) Hepatitis B Diphtheria, tetanus and pertussis Rotavirus Haemophilus influenza type b Pneumococcal Poliomyelitis Measles, mumps, rubella Meningococcal C Varicella Human Papillomavirus (HPV) Influenza

Name an Infectious Disease that can increase with urbanisation/urban crowding (2) Dengue Fever – due to water collecting trash  increase mosquito breeding sites Cholera- due to increased water contamination Cutaneous leishmaniasis- proximity to sand fly vectors

The Malaria lifecycle can be broken down into three phases. Describe the three phases. At which stage are symptoms produced? At which stage is it infectious? (15) Mosquito: in mosquito gut (Transmission) –Gamete  zygote  ookinete  oocyst –When the mosquito takes a blood meal, sporozoites are released into the human's blood Hepatic: (pre-erythrocytic) –within minutes sporozoites attach to and invade liver cells by binding to the hepatocyte receptor –Multiple rapidly into merozoites (asexual, haploid forms, eventually causing hepatocyte rupture Blood (erythrocytic) –Once released from the liver, merozoites bind to the surface of red cells –Within the red cells the parasites grow in a membrane-bound digestive vacuole, hydrolyzing haemoglobin through secreted enzymes. –Develops in trophozoite in the red cell (defined by the presence of a single chromatin mass) then to a schizont which has multiple chromatin masses, each of which develops into a merozoite. –Red Blood cell lyse, releasing merozoites that can infect additional red cells. –Some however develop into sexual forms called gametocytes that infect the mosquito when it takes its blood meal (Transmission) No apparent symptoms until the parasite multiplies in the blood. Cannot reinfect mozzie until gametocytes developed ie. after symptoms start