Airlines and cruise companies across the world are offering refunds or travel credits to pregnant women who are scheduled to visit countries struck by the devastating Zika virus.

So far, 11 airlines and three cruise ship companies have changed their policies as the mosquito-born virus continues to spread.

ZIka is particularly dangerous for pregnant women and is suspected of being the cause of a rise in cases of microcephaly, a condition where babies are born with abnormally small heads.

Qantas does not fly directly to any of the affected countries but its partner, American Airlines, is offering refunds to pregnant women.

Direct carriers including Southwest Airlines, Gol, Brazil, Lufthansa, British Airways and JetBlue Airways are either offering refunds, travel credits or the choice to reschedule flights to any of the affected destinations.

The federal government's Smart Traveller website has warned pregnant women or those planning to conceive to reconsider plans to visit any of the affected countries.

More than a dozen countries across South and Central America and the Caribbean have been impacted by the virus, including Brazil, Colombia, El Salvador, Paraguay, Barbados, plus Samoa in the South Pacific.

Experts warn that the fast-moving virus is spreading at an "explosive" rate and has already been detected in 23 countries. There is currently no vaccine or treatment available

Some countries have even taken the drastic measure of discouraging women from becoming pregnant for the next few years.