Concerns about data sharing and transparency during epidemiological emergencies are not new. Dye and colleagues have announced an initiative called Zika Open through which the manuscripts and respective data submitted to Bulletin of the World Health Organization would be publlished as open access from the date of submission onwards, under a Creative Commons License. This is an important initiative. Here we report challenges faced, particularly in Brazil, for timely, lawful access to governmental collected disease-notification data that are essential to understand the current Zika virus epidemic, and any future public health emergency.