IC11 - Infection prevention in travellers

Question 1

Vaccines that could be demanded for certain countries.

Answer 1

Meningococcus, yellow fever and polio

Question 2

List the travel vaccines available for preventing common infections transmitted by different routes.

Answer 2

Respiratory: Influenza, meningococcus, diphtheria, pertussis, MMR

Food & water: Polio, Hep A, typhoid, cholera

Vector-borne: Yellow fever, Japanese encephalitis

Body & Bodily fluid: Hep B

Transcutaneous spread (bites/ cuts): Tetanus, rabies

Question 3

Advice for urgent travel

Answer 3

Advise for accelerated immunization schedules, counselling on risk avoidance, drug prophylaxis if applicable, and referrals to health services at their destinations.

Question 4

How long do vaccines typically take to elicit some protective response?

Answer 4

2 weeks

Question 5

General considerations pertaining to immunization for travelers.

Answer 5

• Ensure routine (age-appropriate) vaccinations are updated before all travel
• Risk of infection often varies within a risk country so that an exact itinerary needs to be ascertained
• Consult Travel Health Resources for specific recommendations.

Question 6

what is malaria

Answer 6

a mosquito-borne disease caused by the protozoan parasite Plasmodium

Question 7

Mode of transmission of malaria

Answer 7

Primarily through bites of infected female Anopheles mosquitoes

Others: transfusion of contaminated blood products, organ transplantation, vertical transmission (mother to fetus)

Question 8

Most prevalent Plasmodium species, and the most dangerous

Answer 8

Prevalent: P. falciparum, P. vivax
Dangerous: P. falciparum

Question 9

Describe malaria disease epidemiology

Answer 9

Highest transmission is found in Africa South of the Sahara and in parts of Oceania such as Papua New Guinea.

Question 10

lifecycle of Plasmodium

Answer 10

1. Human liver (Exo-erythrocytic cycle)
   * Grow and multiple in liver cells
   * P vivax & P ovale - possible dormancy
2. Human blood (Erythrocytic cycle)
   * Grow and multiple in RBCs
   * Differentiation into sexual stages
   (gametocytes)
   * Clinical symptoms
3. Mosquito (Sporogenic cycle)
   * Mate, growth, multiple, release

Question 11

risk factors for malaria

Answer 11

• between dusk and dawn during colder season/region
• in deserts (excluding the oases)
• Large urban areas usually free of transmission, although malaria can be transmitted throughout urban areas of Africa and possibly India
• at high altitudes
• at the end of/ soon after rainy season

Question 12

non-pharmacologic strategies for malaria prevention

Answer 12

1. Barrier precaution: Wear light-coloured clothes that expose as little skin as possible, Stay indoors, sleep under permethrin-impregnated bed net
2. Insect repellant e.g. DEET (20-50%), Picaridin (at least 20%; kiwi smell may attract flies)

Question 13

When should pre-travel consultation take place?

Answer 13

4-6 weeks before departure

Question 14

Drug used for malaria chemoprophylaxis

Answer 14

• Atovaquone + Proguanil (Malarone®)
• Chloroquine
• Doxycycline
• Mefloquine

Question 15

Commonly used malaria chemoprophylaxis (if there is no resistance)

Answer 15

Chloroquine & Mefloquine

Question 16

Which drug should not be used in the presence of risk of P. falciparum malaria?

Answer 16

Chloroquine & mefloquine (for MDR)

Question 17

Which malaria drugs can be prescribed by pharmacists?

Answer 17

Malarone (POM with exemption) & Chloroquine & Mefloquine (P only)

Question 18

Drug to recommend for last minute travellers

Answer 18

Malarone & doxycycline

Question 19

How long should travellers avoid blood donation after return?

Answer 19

4 months

Question 20

Which malaria drug is the least expensive?

Answer 20

Doxycycline