What are the next best steps for assessing fever in a returning traveler from Japan presenting with rhinorrhea (runny nose) and cough, likely indicating viral bronchitis, and what laboratory tests should be conducted?

From the Guidelines

For a returning traveler from Japan with fever, runny nose, and cough likely representing viral bronchitis, I recommend a focused assessment including complete blood count (CBC), basic metabolic panel, and chest X-ray, as supported by the most recent study on the aetiology of fever in returning travelers and migrants 1. The patient's symptoms, such as fever, runny nose, and cough, are consistent with viral bronchitis, but it is essential to consider other potential causes of fever in returning travelers, including tropical and non-tropical infections.

• The study by 1 found that non-tropical infections, such as respiratory tract infections, were a common cause of fever in returning travelers, accounting for 38.6% of cases.
• In contrast, tropical infections, such as malaria and dengue fever, were less common, accounting for 32.7% of cases.
• The study also highlighted the importance of considering the patient's exposure history, such as travel to rural areas, contact with animals, and consumption of raw foods.
• Based on the patient's symptoms and exposure history, testing for specific infections, such as influenza and COVID-19, should be considered, regardless of vaccination status.
• Blood cultures should be obtained if the patient appears toxic or has a high fever (>101°F), and respiratory viral panel testing can help identify specific viral pathogens.
• Treatment can be supportive with rest, hydration, and antipyretics while awaiting test results, but empiric antibiotics should be considered if bacterial infection is suspected based on clinical presentation or initial lab findings.
• It is also crucial to ask about specific exposures, including contact with animals, consumption of raw foods, and activities in freshwater, to guide further testing and treatment.
• The patient's clinical presentation, including persistent high fever, altered mental status, or respiratory distress, should prompt more extensive workup and consideration of other potential causes of fever.

From the Research

Assessing Fever in a Returning Traveler

The patient's symptoms of rhinorrhea and cough, likely indicating viral bronchitis, require a thorough assessment to determine the cause of the fever.

• A complete risk assessment should be undertaken, including a complete travel history, examination, and further investigations, to help narrow the differential diagnosis 2.
• The focus should be on identifying common causes of fever in returning travelers, such as malaria, dengue fever, enteric fever, or rickettsial disease 3.
• A good history is paramount and needs to include destination, time and duration of travel, type of activity, onset of fever in relation to travel, associated comorbidities, and any associated symptoms 4.

Laboratory Tests

The following laboratory tests should be conducted:

• Metagenomic next-generation sequencing (MNGS) can be used to identify viral pathogens in clinical samples from returning travelers, improving the sensitivity of diagnosis of viral infections 5.
• Standard-of-care diagnostic assays, such as plasma samples, can be used to detect viral infections like dengue virus, hepatitis E, Ebola virus, and hepatitis A 5.
• Nasal/throat swabs can be used to detect respiratory infections, which may not be detected by MNGS of plasma 5.
• Laboratory abnormalities, although nonspecific, can offer a clue to diagnosis when corroborated with clinical and epidemiologic data 4.