Malaria

Question 1

What is malaria?

Answer 1

Malaria is a parasitic infection caused by protozoa of the genus Plasmodium.

Question 2

What are different species of malaria?

Answer 2

Plasmodium falciparum (or P. falciparum) - this is the most life threatening

Plasmodium malariae

Plasmodium vivax

Plasmodium ovale

Plasmodium knowlesi

Question 3

How is malaria transmitted to humans

Answer 3

Bite from infected female Anopheles mosquito

Blood transfusion

Organ transplantation

Question 4

What are risk factors for malaria?

Answer 4

• Travel to endemic area
  
  • No chemoprophylaxis
  • No bed net
  • Immunocompromised
  • Pregnancy
  • <5 years
  • Increasing age

Question 5

What are Sx of malaria?

Answer 5

• Cyclical fever, headache, and massive splenomegaly are key symptoms

Myalgia, diarrhoea

* Arthralgia 
* Anorexia 
* Renal impairment
* Jaundice if falciparum infection 
* Pallor 

Always consider malaria in returning traveller

Question 6

What are features of severe malaria>

Answer 6

• Cerebral malaria
  
  • Severe anaemia
  • Renal failure
  • Shock
  • DIC
  • Acidosis
  • Pulmonary oedema

Parasitaemia > 2%

Question 7

What Ix in malaria?

Answer 7

Thick and thin blood smears: detect parasties, %, type

Rapid diagnostic test: detects in 15 minutes, but can’t tell active and recently treated apart

PCR: good if parasitaemia can’t be detected on films

Bloods: haemolytic anaemia and deranged LFTs

Urinalysis: protein, bilirubin

Cultures likely done if fever

HIV test

Question 8

What is Rx of malaria?

Answer 8

Will depend on the strain.

If chloroquinine sensitive areas, you can use artemisinin-based combination therapy (ACT) or chloroquine

If resistant, use ACT

Quinine and doxycycline can be used if ACT not available

Question 9

How can malaria be prevented?

Answer 9

Bite avoidance

Chemoprophylaxis e.g. malarone, doxycycline, mefloquine