2010 54a Malaria Prevention

Question 1

Which mosquito type spreads malaria?

Answer 1

Anopheles (female)

Question 2

What proportions of UK malaria infections are from each of the plasmodium species?

Answer 2

1. Falciparum: 79%
2. Vivax : 13%
3. Ovale: 6%
4. Malariae: 2%

Question 3

What are the main consequences of malaria in pregnancy?

Answer 3

1. Infective illness
2. Severe anaemia
3. Cerebral malaria
4. Maternal & fetal mortality
5. Reduced birth weight
6. Miscarriage, stillbirth
7. Premature birth
8. Placental parasitaemia

Question 4

What advice should pregnant women be given regarding travel to a malaria-endemic area?

Answer 4

Postpone trip unless unavoidable
Awareness of risk
Bite prevention
Chemoprophylaxis
Diagnosis & treatment promptly

Question 5

What is the risk of contracting malaria during a 1-month stay without chemoprophylaxis?

Answer 5

1. Oceania 1:20
2. Africa 1:50
3. Indian subcontinent 1:500
4. Southeast Asia 1:500
5. South America 1:2500
6. Central Am, Carib 1:10,000

Question 6

What factors affect malaria risk?

Answer 6

1. Location level of transmission
2. Time of year
3. Time of day (anopheles at night)
4. Resistant strains
5. Rural vs urban
6. Length of travel
7. Uptake of interventions

Question 7

What mosquito bite prevention measures can be used?

Answer 7

1. Skin repellants with 50% DEET
2. Room spray with permethrin & pyrethroids
3. Nets impregnated with pyrethroid
4. Full-length clothing with repellants
5. Vaporising mats

Question 8

What is the difference between causal & suppressive malaria chemoprophylaxis?

Answer 8

Causal: against liver schizont stage, continue for 7 days after leaving area
eg Malarone
Suppressive: against red blood cell stage, continue for 4 weeks after
eg Mefloquine

Question 9

What malaria chemoprophylaxis can be given in pregnancy?

Answer 9

1. Mefloquine: 250mg once a week
2. Malarone = atovaquone 250mg + proguanil 100mg, OD
3. Chloroquine 150mg + proguanil 100mg, OD, but resistance

Question 10

What are the strict contraindications to mefloquine?

Answer 10

1. Current or previous depression
2. Neuropsychiatric disorders
3. Epilepsy
4. Hypersensitivity inc to quinine

Question 11

Which malaria chemoprophylaxis drugs are contraindicated in pregnancy & why?

Answer 11

1. Doxycycline: disturbs bone growth, discolours teeth, congenital cataracts
2. Primaquine: haemolysis, esp in G6PD deficiency

Question 12

What standby treatment should be started if malaria is suspected?

Answer 12

1. Antipyretics
2. Quinine 600mg TDS 7 days
3. Clindamycin 450mg TDS 7 days
4. Repeat dose if vomited: full dose of within 30 mins, half if 30-60 mins