The spread of the Zika virus has widened to areas in the north and east, after single cases were found in Yishun, Upper Thomson and Simei. The Ministry of Health (MOH) yesterday also revealed that a second pregnant woman has been diagnosed with the virus.
She has been linked to the original cluster in the Aljunied Crescent/Sims Drive area, where the other expectant mother lives.
The 31 new infections detected as of noon yesterday, and another five found through look-back testing, take the total number of locally transmitted Zika cases here to 151 - less than a week after the first case involving a Malaysian woman living in Aljunied was found.
In a Facebook post a few hours before MOH's latest update last night, Prime Minister Lee Hsien Loong said it was only a matter of time before the Aedes mosquito-borne virus reached Singapore.
"The cases so far have been in Aljunied and Bedok, but we must assume that Zika is elsewhere in Singapore too," he wrote, adding that scientists are still learning about Zika "But we know that for most people, it is mild, and in fact often causes no symptoms at all. Pregnant women are at risk, as they are with other viral infections like dengue and chicken pox. Do take precautions and get tested if you show symptoms.
"Our best defence is to eradicate mosquitoes and destroy breeding habitats, all over Singapore. Do the five-step Mozzie Wipeout. Let's all do our part to fight Zika, and dengue as well."
The National Environment Agency said it is determining areas where mosquitoes are more prevalent, and taking action to reduce the population there - even if the area has no known Zika case.
This is aimed at breaking the disease transmission chain, and preventing further spread.
After Aljunied Crescent/Sims Drive, cases have been found in Paya Lebar Way/Kallang Way, Bedok North Avenue 3, Punggol Way and Joo Seng. Yesterday, MOH said it has found that three cases are not linked to any existing cluster. The affected people live in Yishun Street 81, Tagore Avenue and Harvey Crescent.
By the end of today, there should be posters on Zika and how to wipe out mosquitoes in every Nee Soon South lift, said the area's MP Lee Bee Wah. Checks will also be stepped up to find any pools of water which could allow mosquitoes to breed.
Yishun residents took the news in their stride, highlighting that unless one is pregnant, an infection has little impact. The bigger worry for most was how the virus was spreading. Said bank executive Agnes Teo, 36: "When the first case was reported, it was so far away, and now it's in my neighbourhood."
A resident of a landed estate near Harvey Crescent in Simei, Ms Yip Ming Yen, 38, said her family had started to take precautions such as closing the windows and using insect repellent. "It's definitely a concern," said the lawyer.
Meanwhile, the mother-in-law of the first pregnant woman found to have Zika here told The Straits Times yesterday that the family is feeling a bit better now that she is well and returning home from hospital soon. "She just has to go back later for check-ups regularly."
Malaysia yesterday confirmed its first case of Zika linked to the outbreak here. Its Health Ministry said the 58-year-old financial consultant travelled to Singapore on Aug 19 to visit her daughter, who lives in Paya Lebar.
The daughter also tested positive for Zika, and is one of at least six Malaysians living here who have been infected. More than 50 cases involve foreigners, most of whom are from China and India.
•Additional reporting by Yeo Sam Jo and Janice Heng
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