Name: Fever in the returning traveler — bulletproof documentation — ER Toolkit
Creator: Kim Trinh, MD

In a febrile traveler back from an endemic region, it's malaria until proven otherwise — and the single act that prevents the miss is taking the travel history. The defensible chart records where and when they traveled, the malaria smears (and the plan to repeat them), and the isolation/public-health decisions.

01What's at stake

Falciparum malaria is a medical emergency that can deteriorate within 24 hours, and failure to take a travel history is a leading reason it's missed — contributing to roughly a third of US malaria deaths. More than 10% of malaria patients are afebrile at presentation, and serious tropical infections often mimic an ordinary viral illness — so clinical features alone can't exclude them.

02Can't-miss diagnoses

Malaria (P. falciparum) — the dominant can't-miss; presume it in any febrile traveler from an endemic region within ~30 days.
Dengue / severe dengue — unpredictable critical phase (capillary leak); careful fluids.
Enteric fever (typhoid) — South Asia; adults often constipated, not diarrheal.
Leptospirosis (freshwater/animal exposure), meningococcemia, and the viral hemorrhagic fevers (isolation/public health).
And the "cosmopolitan" causes (influenza, COVID-19, UTI, pneumonia) — but don't anchor on them; co-infection occurs.

03History — the travel history is the test

Where and when — itinerary and timing narrow the differential by endemicity and incubation period. → ask everyone with fever
Incubation: malaria typically 7–14 days (up to 30+); dengue <14 days; typhoid ~1–3 weeks.
Exposures: mosquito, food/water, freshwater, animal, sexual; prophylaxis/vaccination (prophylaxis isn't 100%).
VFR (visiting friends/relatives) and recent-immigrant status — higher malaria risk, possibly fewer symptoms.

Skip the typing

Work the case in the Fever in the Returning Traveler Workup — it records the malaria testing, VHF screen, cultures, and public-health notification, and assembles an MDM that documents the travel history and the can't-miss tropical infections considered.

04Workup & management

Malaria: Giemsa thick AND thin smears (± rapid antigen test) — initial sensitivity is only ~86–90%, so a negative smear is followed by repeat smears at 12–24h. Thrombocytopenia and hyperbilirubinemia raise the suspicion; monitor glucose.
Dengue: NS1 antigen/PCR early, serology later; watch for warning signs; cautious fluids (capillary leak then resorption).
Enteric fever: blood cultures before antibiotics; empiric ceftriaxone/azithromycin (carbapenem for XDR regions).
Severe malaria → IV artesunate + ICU (obtain from health department/CDC; start oral interim therapy while awaiting it). Parasitemia ≥2–5% = severe.
Isolation & public health — airborne/contact precautions and notification when VHF or other high-consequence pathogens are possible; mosquito-bite precautions for dengue in Aedes regions.

05What to document

▼ weak

"Fever and body aches, looks like a viral illness. Discharged with fluids."

▲ defensible

"Fever after return from Ghana 9 days ago (no/partial prophylaxis) — malaria presumed until excluded. Thick and thin smears and rapid antigen sent; given ~86–90% initial sensitivity, repeat smears at 12–24h arranged and patient NOT discharged before initial result. CBC/LFTs (platelets, bilirubin) sent; glucose monitored. Dengue and enteric fever considered; VHF risk assessed (no isolation criteria). If severe (parasitemia ≥2–5% or end-organ): IV artesunate and ICU."

06Where charts fail

Not taking (or documenting) a travel history — the leading cause of missed malaria.
Attributing fever to a "viral illness" without malaria testing in an endemic-region traveler.
Using a single negative smear (or absence of fever) to exclude malaria.
Discharging before the initial malaria result, or without arranged serial smears and follow-up.
Missing severe-malaria criteria (parasitemia, end-organ), or not isolating possible VHF.

07Sources

Wyler B, Avrith N. Emergency department evaluation and management of serious and high-risk infections in the febrile returning traveler. Emergency Medicine Practice (EB Medicine). 2026;28(5).
Jensenius M, Han PV, Schlagenhauf P, et al. Acute and potentially life-threatening tropical diseases in Western travelers (GeoSentinel, 1996-2011). Am J Trop Med Hyg. 2013;88(2):397-404.
Taylor SM, Molyneux ME, Simel DL, et al. Does this patient have malaria? JAMA. 2010;304(18):2048-2056.
Bottieau E, Clerinx J, Van den Enden E, et al. Fever after a stay in the tropics: diagnostic predictors of the leading tropical conditions. Medicine (Baltimore). 2007;86(1):18-25.

Fever in the returning traveler: documentation that holds up