“TOC” to your patients

Has the patient traveled anywhere in the past month?

Assessment of fever or ARI should always include an evaluation of relevant travel history, taking into account both domestic and international travel. International travel is more likely to be associated with uncommon or emerging febrile illness, as well as childhood vaccine-preventable diseases mostly eradicated in Canada but still common in regions where vaccination coverage is low.² However, even travel within Canada might expose a patient to pathogens not native to their home region, such as vector-borne infections endemic to specific areas of Canada and the United States (eg, Lyme disease, West Nile virus). Any positive identification of a patient with fever or ARI who has traveled within the past month should prompt a more focused history (Box 1).²

It is worth noting that only 10% of Canadians seek pretravel medical advice, and that those traveling to visit friends and family are especially likely to forego pretravel consultations, vaccinations, and chemoprophylaxis, and might not accurately perceive or protect themselves against environmental risks.^5,6

For guidance on how best to prepare patients for travel, we recommend that you review the article by Aw and colleagues on travel medicine published in Canadian Family Physician in 2014.⁷

To assess a patient’s risk of travel-related infection, family physicians should check for travel health advisories issued for destinations on the patient’s itinerary. Family physicians should also establish what diseases are endemic to areas the patient visited (eg, malaria, dengue, or chikungunya) and assess what measures the patient took to reduce his or her risk of exposure and infection. Box 2 presents a few publicly accessible online resources where family physicians can find more information.

Malaria (20% to 30%), gastroenteritis (10% to 20%), and respiratory tract infections (10% to 15%) are the most common causes of febrile illnesses in returning international travelers.⁸ However, family physicians must be wary of “premature closure bias” when evaluating illness after international travel and avoid settling on one of these diagnoses before thoroughly investigating all potential infectious causes.

What is the patient’s occupation?

An individual’s occupation can provide clues about risk exposures and potential causes of fever or ARI. Health care workers; laboratory personnel; international humanitarian workers; individuals involved in construction, demolition, or natural resource extraction; and agricultural workers who present with fever or ARI all warrant further assessment.

Health care workers and laboratory personnel might be exposed to common pathogens as a routine part of their jobs, or to rare or emerging virulent agents during an outbreak. Health care workers accounted for more than 40% of SARS infections during the Toronto outbreak⁹; and in the EVD epidemic, both health care and funeral workers were at increased risk of infection.⁴ International humanitarian workers might contract infections rarely seen in Canada, such as malaria, dengue, or tuberculosis. Chemical or uncommon environmental exposures, for example to spores of Histoplasma capsulatum, might be more likely in occupations that involve construction, demolition, or extraction of natural resources.¹⁰ Finally, agricultural environments can be reservoirs for zoonoses, including avian influenza, Q fever, histoplasmosis, psittacosis, and hantavirus pulmonary syndrome.^10,11

If an ill patient reports a higher-risk occupation, his or her family physician should explore the nature of potential exposures and whether appropriate PPE or chemoprophylaxis (where applicable) were available and properly used.

Has the patient recently come into contact with anyone else who has been sick?

Contact tracing is a critical component of global health security. A contact is defined as anyone who has had physical contact with or spent time at the same place as a confirmed case, presumptive confirmed case, or probable case while the case patient was capable of transmitting disease. In South Korea, one man became a MERS “super spreader” in part because the health care workers at the hospital where he presented failed to recognize that he had come into contact with the country’s first case of MERS a month before during hospitalization at a different health care facility.¹² The “super spreader” patient was diagnosed with pneumonia and spent 3 days in the hospital’s crowded emergency department owing to a shortage of beds; by the time he was finally isolated, hundreds of health care workers, patients, and hospital visitors had been exposed.

If a sick contact is identified, it is important to follow up by soliciting information about the sick contact’s travel history and occupation. The Toronto SARS outbreak began when a patient whose grandmother had sickened and died following a trip to Hong Kong presented to an emergency department in Scarborough, Ont, and waited nearly 20 hours to be assessed.⁹ At the time of intake, no one asked whether the patient had come into contact with anyone else who was sick. The cause of the patient’s illness came into focus only after health officials connected his grandmother’s travel history with a recent outbreak of a mysterious respiratory illness in mainland China.