"Any time there is a disease outbreak in Singapore, it tells us how difficult that disease is to control," said US Centers for Disease Control (CDC) director Dr. Tom Frieden. reporters.
Haiti's geographic location and health infrastructure limitations make it a likely candidate for widespread transmission of Zika.
The research adds to evidence that Zika virus infections may bring associated with Guillain-Barré syndrome.
With a population of five million, Singapore has almost double the number of locally transmitted Zika cases as the US.
The study confirms that vertical transmission of the virus occurs in Aedes aegypti mosquitoes.
The Zika virus is circulating in more than 50 countries.
Singapore has reported 56 infections with the virus.
Researchers will have to test the drugs in animal models to see if results can be replicated.
Although the cases were clustered in one neighborhood the Ministry of Health (MOH) has warned the virus could spread further.
Most people who have Zika do not know that they have the virus.