Response to the current Zika virus epidemic

Scientific American has an article that briefly summarizes the link between Zika virus infection during pregnancy and fetal microcephaly. While the circumstantial evidence is strong for a causal link, the article discusses the fact that conclusive evidence will likely only come from retrospective analysis of the current epidemic. Wired magazine has a more speculative article that has some additional interesting facts about the outbreak and the response to it."Most of Brazil's microcephaly cases are in the northeast, and it's unclear why Zika would cause more birth defects there than in other places." Multiple Zika strains or perhaps lagging microcephaly diagnosis may account for this observation. Unfortunately, these types of issues complicate efficient analysis of the current situation. Recent responses to the epidemic reflect serious concern. El Salvador has recommended that pregnancy should entirely be avoided until 2018, and the WHO has declared Zika a public health emergency of international concern allowing it to make decisions that are international law. Do these responses and the responses to the 2014 Ebola outbreak inspire any confidence in our ability to contain these and future frightening viral epidemics? The fact that the vaccine development is already underway, without many confirmed numbers and a lack of conclusive causal evidence, is amazing to me.