A young woman returns from a 4 week trip with a febrile illness. Her family doctor orders a blood film as part of the initial workup, and the following was seen.
What disease does she have and what treatment does she require?
This blood film shows a ring form trophozoite of the unicellular protozoan infection – from a plasmodium species. In other words, this patient has malaria!
A wise infectious disease physician once told me “Fever in a returned traveller is malaria until proven otherwise”.
Differential Diagnosis for Fever in a Returned Traveller:
Infections related to travel (i.e. Tropical Diseases)
-
Malaria
-
Dengue (South america and caribbean)
-
Typhoid (South Asia)
-
Influenza
-
Hepatitis A
-
Zika
-
Chikungunya
Infections unrelated to Travel Location:
(whatever is in your differential diagnosis for local infectious processes e.g. pneumonia, UTI, cellulitis, viral infections)
Non-infectious Etiologies:
Malignancy and DVT always have to be considered in your differential.
Remember to ask returning travellers the following
- Pre-Travel History:
- Did they seek pre-travel advice
-
Immunizations received
-
Routine
-
Recommended
-
Required – Yellow fever, meningococcus
-
-
Malaria prophylaxis
-
Travel itinerary
-
Exact dates
-
transfer points
-
long plane rides – DVT
-
Crowded busses
-
accommodations
-
Time of year
-
-
Exposure History:
-
What did you do while travelling?
-
Animal contact (humans, non-human mammals (brucella, Q fever, Rabies), arthropods, birds, reptiles)
- Food and water (schistosomiasis, leptospirosis)
- Specific Activities (especially sexual)
-
Caves – histoplasmosis, ebola
-
Safari – Malaria, rikettsiosis
-
-
-
CBC and Diferential, Lytes, LFTs, Cr, Albumin
-
Malaria thick and thin film – need three blood films separated in time to rule out, or 2 rapid malaria tests negative
-
Blood cultures
-
Urinalysis and urine cultures
-
Depending on syndrome:
-
NP swab for influenza/RT viruses
-
CXR
-
Dengue serology/chikungunya serology/rickettsial and leptospirosis serology
-
Stool cultures, C Dif +/- ova and parasite
-
“Serology” – Extra red top tube that lab will hold
-
-
Empirically treat for severe malaria if sick (CNS, respiratory involvement)
-
Artesunate 2.4 mg/kg – 5 doses
-
IV quinidine if artesunate not available, administered with doxy or clindamycin
-
-
Non-severe malaria:
-
Atovaquone + Proguanil (malarone – 4 tabs daily x3)
-
Admit everyone with falciparum malaria – ensure they defervesce, keep pills down etc
-
-
Malaria ruled out:
-
Azithromycin +/- Doxy – South and southeast asia
-
Cipro 500 po BID x 7 days +/- Doxy – All other areas
-