The first outbreak of the disease outside of Africa and Asia was in April 2007, on the island of Yap in the Federated States of Micronesia (see figure 2). The condition was characterized by rash, conjunctivitis, and arthralgia, and was initially thought to be dengue. The Chikungunya and Ross River viruses were also suspected. However, serum samples from patients in the acute phase of illness contained RNA of Zika virus. The Zika fever disease process was relatively mild: there were 49 confirmed cases, 59 unconfirmed cases, no deaths and no hospitalizations.