San Juan (AFP) - The US territory of Puerto Rico joined several Latin American countries in recommending Thursday that women avoid getting pregnant for now to protect against the fast-spreading Zika virus.

The virus -- which is "spreading explosively" in the Americas, according to the World Health Organization -- has been blamed for a surge in the number of babies born with abnormally small heads, a condition known as microcephaly.

So far, 19 cases of the mosquito-borne virus have been reported in this US territory in the Caribbean, but none in pregnant women.

In a radio interview, Health Minister Ana Rius recommended that women on the island avoid getting pregnant until more is known about the virus and its effects on children born to infected women.

"It is just a recommendation. It is up to the individual to accept it or not," Rius said.

Colombia, Ecuador, El Salvador and Jamaica have warned women to avoid getting pregnant for the time being.

Microcephaly can cause brain damage in babies or even death.

In Brazil, cases of microcephaly have surged from 163 a year on average to more than 3,718 suspected cases since the outbreak.