Health authorities in Singapore are warning the mosquito-borne Zika virus is no longer contained in one part of the city-state, and is likely to spread further.

In a joint statement, the Ministry of Health and the National Environment Agency confirmed 16 new cases of locally-transmitted Zika as of Monday. That brings the total number to two hundred and fifty eight.

The health ministry also said it would no longer isolate patients because of its "limited effect". Singapore has one of the highest standards of healthcare in Asia.  But the tropical state also sees high rainfall and humid weather, ideal for the breeding of mosquitoes.