Ebola virus

A 40-year-old man presents to the clinic with complaints of low-grade fever, malaise, headache, vomiting, and diarrhea for the past two days. The patient is a healthcare worker and recently traveled to Sierra Leone to assist with an outbreak of an illness in the region. Temperature is 38.9°C (102.1°F), pulse is 115/min, respirations are 24/min, and blood pressure is 115/70 mmHg. Physical examination shows a diffuse erythematous maculopapular rash involving the face, trunk, and arms. Further evaluation confirms the diagnosis of infection with a Filovirus. Which of the following measures could have prevented the development of the disease in this individual?