Malaria & Influenza

Question 1

What is malaria caused by?

Answer 1

Plasmodium protozoa which is spread by the female Anopheles mosquito.

Question 2

There are 4 different species of malaria which cause disease in man.

Which one causes nearly all episodes of severe malaria?

Answer 2

Plasmodium falciparum

Question 3

Clinical features of malaria?

Answer 3

1) Prodrome (non-specific symptoms can precede the onset of fever by several days):
- malaise
- headache
- fatigue
- myalgia
- arthralgia

2) Fever –> often presents as paroxysms (periodic episodes of fever accompanied by chills and rigors)

3) GI symptoms:
- N&V
- abdo pain
- diarrhoea
- may have hepatomegaly

4) Respiratory symptoms –> severe P. falciparum infection can cause pulmonary oedema or ARDS:
- cough
- SOB
- chest pain
- pleural effusion

5) Neurological symptoms (cerebral malaria):
- altered mental status, seizures, ataxia, or coma
- nystagmus, cranial nerve palsies, and focal neurological deficits

6) Anaemia & haemolysis

7) Splenomegaly

8) Renal dysfunction –> AKI

9) Coagulation abnormalities –> DIC

10) Derm manifestations e.g. jaundice

Question 4

What is the gold standard investigation for diagnosis of malaria?

Answer 4

Blood film

Question 5

How can malaria affect platelets?

Answer 5

thrombocythaemia is characteristic

Question 6

How can malaria affect RBCs?

Answer 6

normochromic normocytic anaemia

Question 7

How can malaria affect WCC?

Answer 7

Normal

Question 8

How can malaria affect reticulocytes?

Answer 8

reticulocytosis

Question 9

What is the recommended treatment of uncomplicated P. falciparum malaria?

Answer 9

Artemisinin combination therapy –> Artemether with lumefantrine is the drug of choice

Question 10

Name medications used for malaria prophylaxis

Answer 10

1) Atovaquone + proguanil (Malarone)

2) Chloroquine

3) Doxycycline

4) Mefloquine (Lariam)

5) Proguanil (Paludrine)

6) Proguanil + chloroquine

Question 11

What is a key contraindication of chloroquine?

Answer 11

Epilepsy

Question 12

How long after leaving the malaria-prone area should prophylaxis continue?

Answer 12

Normally 4 weeks

Question 13

What are 2 key side effects of doxycycline?

Answer 13

1) Photosensitivity

2) Oesophagitis

Question 14

What is a key contraindication of Mefloquine (Lariam)?

Answer 14

Epilepsy

Question 15

Why may detecting malaria in pregnant women be difficult?

Answer 15

Diagnosis can be difficult as parasites may not be detectable in the blood film due to placental sequestration.

Question 16

What is 1st line anti-malarial in pregnancy?

Answer 16

Chloroquine

Question 17

Which antimalarial is contraindicated in pregnancy?

Answer 17

Doxycycline

Question 18

What repellent has been shown to repel up to 100% of mosquitoes if used correctly?

Answer 18

diethyltoluamide (DEET) 20-50%

It can be used in children over 2 months of age

Question 19

What is influenza known commonly as?

Answer 19

The flu

Question 20

Clinical features of influenza infection?

Answer 20

• fever greater than 38ºC
• myalgia
• lethargy
• headache
• rhinitis
• sore throat
• cough
• diarrhoea and vomiting

Question 21

When can you consider prescribing antiviral treatment for influenza?

Answer 21

If ALL of the following apply:

1) Patient is in a high risk group or is felt to be at risk of developing a serious complication

2) There is circulating influenza nationally

3) The patient is able to start treatment within 48 hours from the onset of symptoms (36 hours for zanamivir)

Question 22

How soon after onset of symptoms must antivirals be used in influenza?

Answer 22

Within 48 hours

Question 23

What is the 1st line antiviral for influenza?

Answer 23

Oseltamivir

Question 24

Which antiviral for influenza is used for immunocompromised adults and in renal impairment?

Answer 24

zanamivir