The parents of babies who have been to countries infected by Zika are being monitored, as are the potential effects on their babies.

While no cases have yet been reported of an affected baby in New Zealand, The Paediatric Surveillance Unit is watching for it.

Microbiologist Siouxsie Wiles told Andrew Dickens they've been quite specific about the parents they're monitoring.

"It is looking at the impact of people who might have had infections when they were overseas, so this is in case those people weren't tested during pregnancy - this will pick up any of those cases."

Epidemiologist with the New Zealand Paediatric Surveillance Unit Associate Professor Nigel Dickson said it's important the appropriate advice is given to people who have visited, or are considering visiting, the Pacific while pregnant.

"We've got some women I believe who are being monitored who are known to have been infected with Zika during the pregnancy, and they'll be being monitored closely, but we haven't as yet known of any babies who have been born with microcephaly due to Zika in New Zealand."

Nigel Dickson said it would be surprising if there are children with microcephaly or other brain abnormalities who hadn't been picked up during the pregnancy.