SINGAPORE - The Ministry of Health (MOH) announced on Sunday (Jan 24) that it is monitoring the Zika virus situation closely, although no cases of the virus have been detected in Singapore.

"MOH is actively considering precautionary measures against the virus," a ministry spokesman said in a statement to The Straits Times.

The Zika virus is spread by the Aedes mosquito, which is also responsible for transmitting dengue. While symptoms associated with the virus are usually mild - ranging from a slight fever to rash and joint pains - it has been linked to thousands of cases of a birth defect known as microcephaly in Brazil.

The defect causes babies to be born with abnormally small heads, which cause brain damage.

"Currently, South America is seeing a large outbreak, particularly in Brazil," the spokesman added.

"It has also been detected previously in small numbers in several countries in South-east Asia, including Cambodia, Indonesia, Philippines, East Malaysia and Thailand."

The National Environment Agency (NEA) has an ongoing surveillance programme for the virus, according to MOH.

"While we have not detected any case of Zika virus infection in Singapore thus far, we cannot rule out the possibility that there are undetected cases as most infected persons may display mild or no symptoms," it said.

"We have stepped up the programme given the current situation."

On Friday, US health authorities expanded its travel warning for pregnant women to avoid 22 places in Latin America and the Caribbean due to the virus.

MOH has advised travellers to countries with local transmission of the virus to protect themselves from mosquito bites by wearing clothing that cover the body, arms and legs.

They should also use insect repellent and sleep under mosquito nets or in rooms with wire mesh screen to keep out mosquitoes.

Pregnant travellers should undertake strict precautions against mosquito bites.