On June 19, Singapore authorities confirmed two cases of Zika virus infection in Woodlands Street 11 and Street 32. According to the National Environment Agency (NEA), enhanced environmental surveillance detected persistent Zika virus signals in both wastewater and mosquito samples, suggesting ongoing transmission in the area.
As of June 18, there were no officially designated Zika clusters listed on the NEA website, indicating these findings are under close monitoring.
What Is Zika Virus and How Does It Spread?
Zika is a viral infection primarily spread through the bite of an infected Aedes mosquito, the same species that transmits dengue and chikungunya. However, the virus can also be transmitted through sexual contact, blood transfusions, and from a pregnant woman to her unborn child.
Unlike dengue, Zika infections don’t follow a specific seasonal trend in Singapore. The virus remains a concern year-round due to its serious health implications, particularly for pregnant women.
Symptoms and Diagnosis
Most people infected with Zika experience mild or no symptoms. Only about 20% of infected individuals show signs of illness. The most common symptoms include:
- Fever
- Rash
- Headache
- Muscle and joint pain
- Red eyes (conjunctivitis)
- Nausea and vomiting
Symptoms typically appear between 3 and 12 days after being bitten by an infected mosquito and usually last 4 to 7 days.
To confirm a Zika infection, doctors use a reverse transcriptase-polymerase chain reaction (RT-PCR) test, which can detect the virus in blood within the first 5 to 7 days and in urine up to 14 days after symptom onset.
Why Pregnant Women Need to Be Extra Cautious
Zika poses the greatest risk to unborn babies. Studies show that between 1% and 10% of women infected during pregnancy may deliver babies with birth defects. The most common is microcephaly, where the baby is born with an abnormally small head and underdeveloped brain.
Other complications include:
- Hearing and vision problems
- Swallowing difficulties
- Seizures
- Developmental delays
These issues may not be apparent at birth but can emerge as the child grows.
Prevention and Control
Currently, there is no vaccine or specific antiviral treatment for Zika. The focus remains on prevention and symptom management.
NEA recommends the following preventive measures:
- Use mosquito repellent regularly
- Wear long-sleeved clothing
- Sleep under mosquito nets or in rooms with mesh screens
- Remove stagnant water in and around your home
- Empty plant pot trays and containers that collect rainwater
Singapore’s NEA has deployed around 72,000 Gravitraps to monitor mosquito populations across the island.
A Look Back at Zika in Singapore
Zika was first identified in monkeys in Uganda in 1947, with the first major human outbreak recorded in 1952. The virus gained global attention in 2016 when the World Health Organization declared it a public health emergency.
In Singapore, the first imported case was reported in May 2016. By August that year, a local outbreak occurred in Aljunied, resulting in 298 confirmed cases. That outbreak was contained within four weeks.
As of June 12, 2025, Singapore has recorded seven lab-confirmed cases. There were 13 cases in all of 2024.
What Should Pregnant Women Do?
Pregnant women are not more susceptible to infection but face higher risks if infected. The first and second trimesters are considered the most dangerous periods for fetal complications.
If a pregnant woman has visited or resides in a Zika-affected area and is symptom-free, there is no immediate cause for concern. However, if symptoms arise, she should seek prompt medical attention and consult her obstetrician.
Pregnant women showing symptoms can undergo the RT-PCR test. If positive or inconclusive, they will be referred to a maternal-fetal medicine specialist for close monitoring, including regular ultrasounds and possibly amniotic fluid testing.
Final Thoughts
With Zika making a reappearance in Woodlands, public vigilance is key. Residents should take mosquito control seriously, especially those living near identified hotspots. Pregnant women should adopt extra precautions and seek medical advice if symptoms occur.
For the latest updates, refer to the official NEA website and consult healthcare professionals if you have any concerns about Zika virus transmission.
