Mayaro and Chikungunya; two alphaviruses with clinical and epidemiological similarities

In 1780, Philadelphia suffered an unusual outbreak of hemorrhagic fever, which years later was identified as dengue (1). One hundred years later, in Memphis, 1500 people died from yellow fever, which caused residents to abandoned the city (2). Even though these stories may seem anecdotes, they show how dramatic hemorrhagic arbovirus outbreaks can be.