Hantavirus pulmonary syndrome — DTM&H MCQ

Correct answer: E — Hantavirus pulmonary syndrome

The correct answer is E, Hantavirus pulmonary syndrome. Progressive dyspnoea, bilateral pulmonary infiltrates and hypotension developing 5 days after cleaning a rural barn with rodent dropping exposure in Argentina is the classic prodrome-to-cardiopulmonary phase transition of hantavirus (cardio)pulmonary syndrome caused by Andes virus, the hantavirus endemic to Argentina and Chile. UKHSA guidance confirms that progression to hantavirus cardiopulmonary syndrome can be rapid, with increasing shortness of breath, pulmonary oedema and cardiovascular shock following an incubation period after rodent excreta exposure. Infection follows inhalation of aerosolised excreta from infected rodents disturbed during activities such as barn cleaning, exactly the exposure described. Andes virus is also notable among hantaviruses for documented, albeit rare, person-to-person transmission, which is clinically and epidemiologically relevant in South American case clusters. Why the other options are wrong: D. Leptospirosis with pulmonary haemorrhage: transmitted via contact with water or soil contaminated by infected urine, not primarily dry barn dust, and typically features jaundice, conjunctival suffusion and renal impairment rather than the rapid non-cardiogenic pulmonary oedema and shock seen here. C. Histoplasmosis: acquired by inhaling spores from bird or bat droppings in caves or bird roosts, causes a subacute pulmonary or disseminated illness, and does not produce acute cardiovascular shock within days. B. Community-acquired pneumonia: does not explain the specific rodent dropping exposure history, and typical bacterial pneumonia does not cause this abrupt capillary leak syndrome with hypotension. A. Melioidosis: caused by Burkholderia pseudomallei from contaminated soil or water in endemic regions of Southeast Asia and northern Australia, not South America, and rodent droppings are not the vector. Key point: rodent dropping exposure plus rapidly progressive non-cardiogenic pulmonary oedema and shock in South America points to Andes virus hantavirus pulmonary syndrome, not leptospirosis or histoplasmosis.

Reference: UKHSA, Hantaviruses guidance, GOV.UK, https://www.gov.uk/guidance/hantaviruses