Have you heard about this Zika virus? I hadn't heard of it until a few weeks ago. It makes unborn babies look like Dobby the hoose elf, with an underdeveloped brain. Central American governments are suggesting that you shouldn't get pregnant until 2018.
The World Health Organization says it's spread by mosquitoes and there is no cure for it. It could reach pandemic scale and come back in 10 years then there might be a vaccine of some sort.