Malaria

Question 1

malaria is the

Answer 1

commonest imported infection to the UK (1500/ year)

Question 2

disease vector

Answer 2

female Anopheles mosquito

Question 3

how many species of plasmodium

Answer 3

5

Question 4

which are the main malaria causing plasmodium

Answer 4

Plasmodium falciparum (most common) and Plasmodium vivax

Question 5

patient risk factors

Answer 5

Risks of more severe disease:
• Young children and infants
• Older adults
• Pregnant women

Question 6

most cases outside Africa

Answer 6

occurs in travellers and immigrants returning from countries where malaria transmission occurs (sub-Saharan Africa and South Asia)

Question 7

resident of a malaria region may be exposed to the disease so frequently that they acquire

Answer 7

partial immunity- lesson severity of malaria symptoms

Question 8

malaria infections affect which system

Answer 8

CVD
Resp
Renal
CNS
Blood
Metabolic

Question 9

symptoms and signs of Severe falciparum malaria: CVS

Answer 9

• Tachycardia
• Hypotension
• Arrhythmias

Question 10

symptoms and signs of Severe falciparum malaria: Resp

Answer 10

• ARDS

Question 11

symptoms and signs of Severe falciparum malaria: GI

Answer 11

• Diarrhoea
• Deranged LFTs
• Bilirubin

Question 12

symptoms and signs of Severe falciparum malaria: Renal

Answer 12

acute kidney injury

Question 13

symptoms and signs of Severe falciparum malaria: Blood

Answer 13

• Low/ normal WCC
• Thrombocytopenia
• DIC
• Low Hb
• Anaemia

Question 14

symptoms and signs of Severe falciparum malaria: metabolic

Answer 14

• Metabolic acidosis

* Hypoglycaemia

Question 15

patient symptoms

Answer 15

• Fever (cycle every 3rd or 4th day)
• Chills
• Flu-like illness
• Nausea and vomiting
• Muscle pain and fatigue
• Sweating
• Chest or abdominal pain
• Dry Cough
• Enlarged spleen

Question 16

modes of transmission of malaria

Answer 16

• Mosquito vector
• From mother to unborn child
• Blood transfusions
• Sharing needles used to inject drugs

Question 17

lifecycle of plasmodium

Answer 17

1) Mosquito feed on human, simultaneously injecting malaria sporozoites into the bloodstream
2) Sporozoites make way to liver where they infect hepatocytes
3) Within heptocytes sporozoite develops into mature schizont creating many merozites
4) Merozites burst out of the hepatocyte and journey back to the bloodstream and infected healthy blood cells
5) Merozites reproduce and rupture the RBC, liberating more merozites
6) Merozoites develop into gametocytes which can remain in the bloodstream for several days to be injected by other mosquitos
7) The blood stage parasites are those that cause the symptoms of malaria.
8) When certain forms of blood stage parasites (gametocytes, which occur in male and female forms) are ingested during blood feeding by a female Anopheles mosquito, they mate in the gut of the mosquito and begin a cycle of growth and multiplication in the mosquito.
9) After 10-18 days, a form of the parasite called a sporozoite migrates to the mosquito’s salivary glands.
10) When the Anopheles mosquito takes a blood meal on another human, anticoagulant saliva is injected together with the sporozoites, which migrate to the liver, thereby beginning a new cycle.

Question 18

management: prevention

Answer 18

ABC

Question 19

A

Answer 19

assess risk

• Knowledge of at risk areas
• Regular/returning travellers

Question 20

B

Answer 20

bite prevention

• Repellent, adequate clothing, nets
• Chemoprophylaxis before travel
• Must include regular/returning travellers

Question 21

C

Answer 21

chemoprophylaxis

• Specific to region
• Start before & Continue after return (generally 4 weeks)

Question 22

diagnosis

Answer 22

• Serology (blood film x3)
• PCR
• Drug-resistance testing

Question 23

gold standard

Answer 23

microscopic examination

Question 24

rapid diagnostic test

Answer 24

detects specific malaria antigen sin the blood

Question 25

preferably treatment for malaria should no be imitated unti

Answer 25

diagnosis

Question 26

treatment should be guided by

Answer 26

* The infecting plasmodium species * Clinical status of the patient * Expected drug susceptibility of the infecting parasite * Previous use of antimalarials including those taken from malaria and chemoprophylaxis

Question 27

treatment for P. falciparum (malignant)

Answer 27

* Artesunate | * Quinine and doxycycline

Question 28

treatment for P. viva, vale, malariae (benign)

Answer 28

• Chloroquine • Dormant hypnozoites (liver)  Can recur months-years later  Give additional primaquine

Question 29

if left untreated the pt will

Answer 29

develop severe complications and die

Question 30

complications

Answer 30

``` cerebral malaria breathing problems organ failure anaemia low blood sugar ```

Question 31

Cerebral malaria.

Answer 31

If parasite-filled blood cells block small blood vessels to your brain (cerebral malaria), swelling of your brain or brain damage may occur. Cerebral malaria may cause seizures and coma.

Question 32

Breathing problems.

Answer 32

Accumulated fluid in your lungs (pulmonary edema) can make it difficult to breathe.

Question 33

Organ failure

Answer 33

Malaria can cause your kidneys or liver to fail, or your spleen to rupture. Any of these conditions can be life-threatening. - due to destruction of RBC- splenomegaly

Question 34

anaemia

Answer 34

Malaria damages red blood cells, which can result in anemia.

Question 35

low blood sugar

Answer 35

Severe forms of malaria itself can cause low blood sugar (hypoglycemia), as can quinine — one of the most common medications used to combat malaria. Very low blood sugar can result in coma or death.