Paper short abstract:

This paper assembles narratives about the origins of the Zika virus and microcephaly from a range of new media and ethnographic sources in Brazil in order to ask what evidence is marshaled in circulating rumors, what threat they identify, and how they claim the authority of truth.

Paper long abstract:

What counts as evidence in rumors that circulate online? When the Zika virus was first identified and began receiving news coverage in Brazil in early 2015, the Brazilian Minster of Health responded with what was almost a snicker. The country had bigger concerns, said the government, than an infection so mild most people wouldn't even realize they had it. As babies with microcephaly started showing up in surprising numbers in hospitals in July, however, that very mildness appeared to have been a trick. A link between the virus and the babies was quickly suspected and gradually confirmed by biomedical researchers and doctors, but in stories shared online, forwarded by WhatsApp groups, and illustrated in YouTube videos, alternative explanations proliferated. These ranged from claims that the virus had been brought to Brazil by Cuban doctors or illegal African immigrants; to a secret mass sterilization campaign, spread by genetically modified mosquitos; to suggestions that the real cause of microcephaly was an insecticide. This paper assembles narratives about the origins of the Zika virus and microcephaly from a range of new media and ethnographic sources in order to ask what evidence is marshaled in these rumors, what threat they identify, and how they claim the authority of truth. Put differently, what are their modes of veridiction (Foucault 1998, 2008), and what does this tell us about how evidence works in online spaces in Brazil today?