Infectious Diseases in the Returning Traveler

Key Features

• Most infections are common and self-limited

• Identify patients with transmissible diseases that require isolation

• The incubation period may be helpful in diagnosis

• Less than 3 weeks following exposure may suggest dengue, leptospirosis and yellow fever; > 3 weeks suggests typhoid fever, malaria, and tuberculosis

• Travel history should include directed questions regarding

  • Geography (rural versus urban, specific country and region visited)

  • Time of year

  • Animal or arthropod contact

  • Unprotected sexual intercourse

  • Ingestion of untreated water or raw foods

  • Historical or pretravel immunizations

  • Adherence to malaria prophylaxis

Clinical Findings & Differential Diagnosis

• Fever and rash may indicate

  • Dengue

  • Chikungunya

  • Zika virus

  • Viral hemorrhagic fever

  • Leptospirosis

  • Meningococcemia

  • Yellow fever

  • Typhus

  • Salmonella typhi

  • Acute HIV infection

• Pulmonary infiltrates may be caused by

  • Tuberculosis

  • Ascaris

  • Paragonimus

  • Strongyloides

• Meningoencephalitis may be caused by

  • N meningitides

  • Leptospirosis

  • Arboviruses

  • Rabies

  • Cerebral malaria

• Jaundice may be indicative of

  • Hepatitis A

  • Yellow fever

  • Hemorrhagic fever

  • Leptospirosis

  • Malaria

• Fever without localizing symptoms or signs may be caused by

  • Malaria

  • Typhoid fever

  • Acute HIV infection

  • Rickettsial illness

  • Visceral leishmaniasis

  • Trypanosomiasis

  • Dengue

  • COVID-19 (SARS-CoV-2)

• Traveler's diarrhea (see Diarrhea, Traveler's)

Diagnosis

• Laboratory tests and imaging studies are based on clinical suspicion and may include

  • Complete blood count with differential, electrolytes, blood cultures, serologic tests

  • Thick/thin smears of peripheral blood

  • Urinalysis

  • Liver biochemical tests

  • Chest radiograph

  • Placement of a PPD (purified protein derivative)

  • Examination of sputum for acid-fast bacilli and possibly for ova and parasites

  • Lumbar puncture

  • Nape biopsy (if rabies is suspected)

  • Bone marrow biopsy

• Next-generation sequencing (NGS) of plasma or body fluids such as cerebrospinal fluid is used increasingly as an adjunctive diagnostic modality when traditional methods have not yielded a diagnosis

• See also Diarrhea, Traveler's

Treatment

• See individual infection for Treatment recommendations