Travel Related Infections Flashcards
(40 cards)
Why is it so important to always take a travel history?
There is increased global travel
What is the difference between calendar and relative time?
Calendar time- duration of symptoms
Relative time- how long ago did they go away
*think about incubation periods
Why is a travel history important?
- Recognise important disease (that may be rare or unknown in the UK)
- Different strains of pathogen may be found elsewhere in the world. (Antigenically different, impacts on protection/detection, antibiotic resistance)
- Infection prevention ( on the ward and in the lab- samples may nee to be handled differently )
What do you need to consider when looking at someone who may have a travel infection?
Where (have they been)
When (did symptoms begin)
What (are the symptoms/signs)
How (did they acquire it)
List some regions that are known to harbour travel infections?
Sub-Saharan Africa
S.E asia
S/C america
List some methods by which someone may acquire an infection abroad?
Food/water Insect/tick bite Swimming Sexual contact Animal contact (bite/safari) Beach/recreational activities
What are the key aspects of travel history that we need to know?
- any unwell travel companions/ contact?
- pre-travel vaccinations/ preventative measures?
- recreational activities?
- healthcare exposure?
What is the most important foreign infection you need to consider?
Malaria
What are the vectors for malaria?
Female anopheles mosquitos
What are the 3 most common species of malaria virus?
Plasmodium falciparum (africa) Plasmodium vivax (india) Plasmodium ovale (india)
What is the incubation period of malaria?
Minimum 6 days
P.falciparum: up to 6/12
P.vivax/ovale: up to 1 year +
What is the common history taken from someone with malaria?
Fever chills and sweats- cycle every 3rd or 4th day
What are the signs seen with someone with malaria. Upon examination?
Often few signs except fever
+/- splenomegaly
What organism causes typhoid/enteric fever?
Salmonella typhi
What are the features of severe malaria in adults?
- Impaired consciousness or seizures
- Renal impairment
- Acidosis
- Hypoglycaemia
- Pulmonary oedema or acute respiratory distress syndrome (ARDS)
- Hb <80 g/L
- Spontaneous bleeding/disseminated intravenous coagulation
- Haemoglobinuria (without G6PD deficiency)
- Parasitaemia >10%
- Tachycardia
- Hypotension
- Arrhythmias
- GIT-diarrhoea, abnormal LFTs, bilirubin raised
Where would you go to look up information on travel related infections?
WHO
Public health England
What investigations would you ask for when dealing with someone who you suspect of having malaria?
Blood smears (need 3 negatives to rule out malaria)
FBC, U&Es, LFTs, glucose, coagulation
Head CT if CNS symptoms (are they slipping in and out of consciousness)
CXR (if there are respiratory complications)
*malaria should be managed by an ID physician
What treatment should be given for malaria (plasmodium falciparum)?
- 1st line is IV artesunate for 7 days, switch to oral when improving
- if not available, can give IV quinine plus PO doxycycline; monitor blood glucose on treatment
What treatment should be given for malaria? (Plasmodium vivax/ovale)
Chloroquine + primaquine
And hypnozoites to combat the dormant liver stage
*the problem with this form of malaria is that is can lay dormant in the liver for some time and then recurs months later, the drugs given are designed to stop this happening
How would you prevent someone catching malaria?
ABC
A: assess risk- have a knowledge of the risk areas
B: bite prevention- repellant, adequate clothing, nets.
C: chemoprophylaxis- specific to region, start before and continue after return (generally 4 weeks)
What is another word for typhoid and paratyphoid?
Enteric fever
Mainly in asia, but also Africa and s america
What is the mechanism of infection for enteric fever?
-faecal oral from contaminated food/water
What causes salmonella?
Salmonella enterica serovar typhi
Salmonella enterica serovar paratyphi
What type of bacteria is salmonella enterica?
Gram-negative bacilli
