Session 9 - Travel Related Infections Flashcards Preview

Phase 1 - S2 Infection (M) > Session 9 - Travel Related Infections > Flashcards

Flashcards in Session 9 - Travel Related Infections Deck (35)
Loading flashcards...
1

What is the most important piece of knowledge to have when you suspect someone has a travel related infection?

  • How long they have had symptoms for
  • What their recent travel history is
  • Where they have recently travelled to

2

What is a bacterium that is commonly seen in travel related infections?

Rickettsia

3

What is special about Rickettsia as compared to other bacteria?

  • Can only live within other cells
  • Doesn't have the same gram staining capabilities as normal bacteria
  • Needs a vector 

4

What are some other travel related infections?

  • Malaria
  • Dengue
  • Enteric fever

5

Why is a patient's travel history so important?

  • Recognise imported diseases
  • May be a different strain of a pthogen
  • Can prevent infection from spreading

6

How can people acquire travel related infections?

  • Contaminated food and water
  • Insect or tick bite
  • Swimming in contaminated water
  • Sexual contact
  • Animal contact
  • Beach or recreational activities

7

What is the organism that causes malaria?

Plasmodium (a parasite)

8

What are the four main species of malaria?

  • Plasmodium flaciparum (msot common)
  • Plasmodium vivax
  • Plasmodium ovale
  • Plasmodium malariae 

9

What is the vector that trasmits malaria?

Female anopheles mosquitos 

(night biter mosquitos)

10

What is malaria's incubation period?

  • A minimum of 6 days
  • P. falciparum: up to 6 months
  • P. vivax/ovale: up to a year

11

What are the common symptoms of malaria?

  • Headache
  • Fever
  • Chills and sweating
  • Dry cough
  • Spleen enlargement 
  • Nausea and vomitting
  • Muscle fatigue and pain

12

How would you classify severe falciparum malaria?

This is when the parasites occupy more than 2% of red blood cells.

13

What are the risks with severe malaria?

Cardiovascular:

  • tachycardia
  • hypotension
  • arrhythmias

Respiratory:

  • acute respiratory distress syndrome (ARDS)

Gastrointestinal:

  • bilirubin (haemolysis)

Renal:

  • acute kidney injury

Blood:

  • thrombocytopenia

Metabolic:

  • metabolic acidosis
  • hypoglycaemia

Also susceptible to secondary infections.

14

How does the malaria parasite infect the body?

  • Parasite enters the blood stream
  • Enters the liver
  • Multiplies in the liver
  • Re enters the bloodstream and red blood cells
  • Leads to red blood cells bursting
  • Some parasites become gametocytes that can be picked up by mosquitos 

15

How do you test for malaria?

Blood smear

  • Done three times and to be cleared of infection, must receive 3 negatives

FBC, Urea and Electrolytes, Liver Function Tests

Chest X ray

16

How do you treat P. falciparum malaria?

  • Artesunate
  • Quinine and Doxycycline

17

How do you treat the other three forms of malaria?

  • Chloroquinine and primaquine
  • Hypnozoites (liver stage)

Can recur months-year later

18

How can malaria be prevented?

  • Know the risk areas
  • Prevent bites (insect repellant, clothing etc.)
  • Chemoprophylaxis 
    • specific to the region
    • start before and continue after return (normal course is 4 weeks)

19

Where can someone get enteric fever?

  • Found in mainly asian countries
  • Due to poor sanitation

20

What is the mechanism of infection for enteric fever?

Faecal-oral transmission from contaminated food and water.

Source comes from cases or carriers (human pathogen only).

21

What is the name of the bacteria that causes enteric fever?

Salmonella typhi

22

What kind of bacteria is Salmonella typhi?

  • Aerobic
  • Gram-negative rod bacteria

23

What are some of the virulence factors for enteric fever?

  • Gram negative endotoxin
  • Invasin - allows intracellular growth
  • Fimbriae that can adhere to epithelium over the ileal lymphoid tissue

24

What are the common symptoms of enteric fever?

  • Fever
  • Headache
  • Abdominal discomfort
  • Constipation
  • Dry cough
  • Bradycardia

25

What is the incubation period of enteric fever?

7-14 days.

26

What are some complications that can arise from enteric fever?

  • Intestinal haemorrhage and perforation
  • Has a 10% ortality if left untreated

27

How do you test for enteric fever?

  • Blood culture should be taken (main one)
  • Faeces test
  • Serology not reliable in these cases

28

How do you treat enteric fever?

Enteric fever has increasing ability to resist drugs (highly drug resistant).

Therefore is normally treated with IV ceftriaxone.

Can also be treated with azithromycin for 7-14 days.

29

How can enteric fever be prevented?

  • Food and water hygiene precautions
  • Typhoid vaccine can be given if going to areas of high risk
    • this is either an antigen or a live attenuated (less dangerous) version of the bacteria

30

What is the microorganism that causes dengue fever?

Dengue fever is caused by the arbovirus.

It has 4 different serotypes.