Previous exposure to dengue may make Zika worse, scientists find
By Kate Kelland LONDON (Reuters) – Scientists studying the Zika outbreak in Brazil say previous exposure to another mosquito-borne virus, dengue, may exacerbate the potency of Zika infection. The scientists said their results, published in the journal Nature Immunology, suggested that some dengue antibodies can recognize and bind to Zika due to the similarities between the two viruses, but that these antibodies may also amplify Zika infection in a phenomenon called antibody-dependent enhancement. This effect is already known with dengue, they said, and is thought to explain why, when a person gets dengue fever a second time, the infection is often more serious than the first.