A virus with no treatment or vaccine is now likely to spread throughout the Americas.
The World Health Organization says the mosquito-borne Zika virus is expected to spread to all countries
in North and South America except for Canada and Chile.
The virus has been linked with rising cases of microcephaly, a disorder in which infants
are born with smaller craniums and brains.
One-and-a-half million people in Brazil are thought to have been infected by the virus.
The situation is so serious that Brazil, Colombia and El Salvador have warned women to avoid
becoming pregnant for two years.
The WHO says any women planning to travel to affected areas should see a doctor before
travelling and on return.