There could already be 40,000 people carrying Zika in the US
New Scientist - 08/03/2016
As many as 40,000 people in the US could already be carrying the Zika virus, having caught it while travelling abroad, a team analysing the epidemic has warned.
This figure was calculated by extrapolating from the numbers of pregnant women who have been confirmed to be carrying the virus after visiting countries where it is established, like Brazil and Colombia. In most people, Zika has no symptoms or causes only mild illness, but babies born to women infected during pregnancy can havemicrocephaly, which can cause brain damage.
Infected pregnant women who have travelled are the best proxies for the total number of travel-related cases, saysAlessandro Vespignani at Northeastern University in Boston, Massachusetts. This is because pregnant women see medical professionals more regularly, so any infections they have are more likely to be detected.