Just a year or two after her son had dengue, she contracted Zika. Both diseases are mosquito-borne.
So the positive Zika diagnosis did not come as a surprise to Ms Hong Hai Cheng, 46, one of two residents with the virus in the second Zika cluster of the year, in Flower Road/Hendry Close.
The Hendry Close resident said mosquitoes are a perennial problem there. She told The Straits Times in Mandarin: "I was likely bitten near my home. There's a drain on the premises of a nearby house, and water always collects there when it rains. I've tried to talk to the owner, but it seems no one is around."
Ms Hong, who manages Korean food stalls here, told ST yesterday she is well and has returned to work after having been discharged from Mount Alvernia Hospital on Sunday.
The other patient in the cluster does not live with her. In the first cluster, in Simon Place, a married couple from the same home had the virus. No one in the two clusters is pregnant. The clusters are near each other and also Kovan. The first was notified on March 28; the second was told on Thursday. Mosquito-control operations are ongoing in both areas.
Ms Hong found rashes all over her body and visited a clinic in Hougang on March 30, thinking it was a skin problem. The doctor suspected she had Zika, which can cause rashes and mimic a mild cold. She was advised to go to a hospital if she had a mild fever the next day. She did, so she went to hospital on March 31.
She stayed calm as her fever did not exceed 38 deg C and she did not have much discomfort. She said: "Friends visited me and found it hard to believe as I didn't look sick. I was more afraid of the doctor taking my blood than of Zika itself."
She has asked her three sons to spray more repellent. Since late last year, she has also installed electronic insect repellent devices.
The area has mainly private housing, with landed properties and condominiums. National Environment Agency officers and grassroots volunteers have distributed insect repellent and Zika information leaflets to raise awareness.
Responses were mixed when residents were asked if they were more concerned after hearing about the latest cluster.
Retired stationery wholesaler Yeo Kwang Sen, 85, said he is worried as Ms Hong lives near his home, but he has been taking precautions. "I try to ensure there is no stagnant water in my home, but there's only so much you can do. The mosquitoes fly everywhere."
Domestic helper Thant Thant Oo, 40, who lives along the same road, is less worried. She said the authorities have been fogging the area and conducting regular checks to spot signs of mosquito breeding.
Hougang resident George Tan, 70, who is unemployed, said he is "not worried at all". "Prevention is done every day as I do not leave stagnant water around, and I always overturn pails and watering cans."