Diagnostic Approach for Fever and Rash in Returning Travelers

Initial Assessment and Investigations

The workup for a patient with fever and rash all over the body with travel history should prioritize ruling out potentially life-threatening tropical infections, particularly malaria, dengue fever, rickettsial infections, and viral hemorrhagic fevers, according to the Centers for Disease Control and Prevention (CDC) 1, 2
Obtain specific information about countries visited, exact dates of travel, activities undertaken, accommodations, and any known exposures to insects, animals, or ill individuals to guide the diagnostic approach 3
Determine the onset of fever in relation to travel and progression of rash to understand the timeline of symptoms 3
Note the presence of headache, myalgia, arthralgia, gastrointestinal symptoms, respiratory symptoms, or neurological manifestations as associated symptoms 4

Perform malaria testing with three thick and thin blood films over 72 hours and/or rapid diagnostic test (RDT) for any patient who has visited a tropical country within the past year, as recommended by the World Health Organization (WHO) 3
Conduct a complete blood count to look for thrombocytopenia, lymphopenia, or eosinophilia, which can indicate various infections 3
Obtain blood cultures, at least two sets, before initiating antibiotics, which is essential for diagnosing enteric fever 3
Assess liver function tests and renal function to evaluate for organ involvement 3
Perform urinalysis to check for proteinuria, hematuria, or hemoglobinuria, which can be indicative of certain infections 3
Consider a chest X-ray if respiratory symptoms are present 3

For patients with fever and rash, consider dengue testing with PCR or NS1 antigen test, and IgM serology if more than 5 days have passed since symptom onset, as suggested by the CDC 1
Consider HIV testing if acute seroconversion illness is suspected, especially with a maculopapular rash 1
For patients with exposure to ticks, consider rickettsial testing with acute phase serum and convalescent serum, and empiric doxycycline treatment 1, 4
If travel to endemic areas is reported, consider chikungunya testing with PCR or IgM 1, 4
Assess the risk of viral hemorrhagic fever (VHF) and contact regional infectious disease centers for guidance on appropriate testing if travel to endemic areas is suspected 1

Treat malaria empirically if there is high suspicion and the patient appears ill, even with initial negative tests, as recommended by the WHO 3
Consider empiric doxycycline for rickettsial infections if exposure to ticks in game parks with fever, headache, and rash/eschar is suspected 1, 4
For enteric fever, consider empiric ceftriaxone while awaiting culture results if the patient is clinically unstable with an appropriate travel history 1
For dengue, provide supportive care with close monitoring of platelet count and hematocrit, and avoid aspirin due to bleeding risk, as advised by the CDC 1

Implement appropriate isolation precautions for suspected cases of viral hemorrhagic fevers, measles, enteric fever, or other contagious diseases, as recommended by the CDC 5
Alert laboratory staff when suspecting infections that pose occupational hazards, such as brucellosis, viral hemorrhagic fevers, or Q fever 5
Report notifiable diseases to local health protection units, as required by the WHO 5