Fake medicines are a 21st-century scourge, but they've been around for a long time. This advertising trade card for snake oil was printed in New York City around 1880.
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The effects of malaria in the brain are clear: A healthy brain, right, has many grooves and crevices. But when the brain swells up, left, these crevices smooth out.
Courtesy of Michigan State University
Do you know what the deadliest disease is? Hint: It's not Ebola (viral particles seen here in a digitally colorized microscopic image, at top right, along with similar depictions of other contagious diseases)