Singapore on Friday confirmed two cases of locally transmitted infections of the mosquito-borne Zika virus, bringing the total number of reported cases in the city-state this year to eight.
The viral disease carried by mosquitoes has spread to more than 60 countries since an outbreak was identified in Brazil in 2015, raising alarm over its link to microcephaly, a rare birth defect.
The National Environment Agency (NEA) said it had begun inspections and spraying with insecticide in some parts of the city.
“Residents are urged to maintain vigilance and continue to eliminate mosquito breeding habitats, as there could still be asymptomatic or mild, undiagnosed cases which might result in further transmission of the virus,” the agency said in a statement.
Most people who are infected with Zika have mild symptoms but infections in pregnant women have been linked to microcephaly and other brain abnormalities in babies.
In adults, Zika infections have also been linked to a rare neurological syndrome, known as Guillain-Barre, that can cause paralysis.
The NEA has urged citizens to take precautions against mosquitoes in the coming summer months, usually the peak season for another mosquito-borne disease, dengue fever, media reported.
The Aedes aegypti mosquito, the main carrier of dengue, also transmits the Zika virus.
Singapore has now reported eight Zika cases this year, government data shows. Last year, more than 400 people became infected with the virus, following discovery of the first case in August.