First Case of Locally Transmitted Zika Virus Infection in Singapore
The Ministry of Health (MOH) and National Environment Agency (NEA) have been informed of a case of Zika virus infection. The patient is a 47-year-old female Malaysian who resides at Block 102 Aljunied Crescent and works in Singapore. As she had not travelled to Zika-affected areas recently, she was likely to have been infected in Singapore.
The patient had developed fever, rash and conjunctivitis from 25 August. She visited a general practitioner (GP) on 26 August and was referred to the Communicable Diseases Centre (CDC) at Tan Tock Seng Hospital, where she was tested positive for Zika on 27 August. She has since been hospitalised for observation at the CDC. The patient is currently well and recovering.
With the presence of Zika in our region and the volume of travel by Singaporeans as well as tourists, it is inevitable that there will be imported cases of Zika into Singapore. There is also risk of subsequent local transmission, as the Aedes mosquito vector is present here. While MOH and NEA have stepped up precautionary measures, we expect that there may be further cases, as most infected persons may display mild or no symptoms.
Areas in the Vicinity of the First Local Case of Zika
Screening of Contacts
MOH is screening the patient’s close contacts, including household members. MOH is also carrying out Zika testing on others living and working in the area who have symptoms of fever and rash. At this point, three other suspect cases – two in a family who live in the area and an individual who works in the area – had preliminarily tested positive based on their urine samples. They are pending further confirmation tests.
MOH has alerted all GPs around the patient’s home and workplace to be extra vigilant and to immediately report patients with symptoms associated with Zika virus infection to MOH. MOH and NEA will also actively alert residents in the vicinity to seek medical attention should they develop symptoms.
Minister for Health, Mr Gan Kim Yong, said, “MOH and NEA are working together to carry out vector control and testing of residents in that area with fever and rashes so as to reduce the risk of further spread. I encourage those who are unwell and with these symptoms to visit their doctors for medical attention. We have also alerted our clinics in the area to look out for suspect cases and refer them to the CDC for testing."
For now, as an added precaution, all suspect cases of Zika virus infection will be isolated while awaiting confirmation of the blood test results.
NEA has intensified vector control operations to control the Aedes mosquito population in the vicinity of Aljunied Crescent by immediately deploying about 100 officers to inspect the area. NEA is also conducting outreach efforts and distributing Zika information leaflets and insect repellents to residents living in the area. NEA’s intensified vector control operations include:
- Inspecting all premises, ground and congregation areas
- Conducting mandatory treatment such as ultra-low volume (ULV) misting of premises and thermal fogging of outdoor areas to kill adult mosquitoes
- Increasing frequency of drain flushing and oiling to prevent breeding
- Public education outreach and distribution of insect repellents
NEA will also be activating partner agencies of the Inter-Agency Dengue Task Force to step up localised search and destroy efforts in their respective areas to help reduce the risk of the virus spreading further.
The patient’s residence at Aljunied Crescent is not located in an active dengue cluster. However there are two active dengue clusters nearby, each with two cases. Prior to the Zika case being notified, NEA had been inspecting the premises in nearby dengue clusters to detect and destroy mosquito breeding.
As the majority of people infected with the virus do not show symptoms, it is possible that some transmission may already have taken place before this case of Zika was notified. Hence, even as NEA conducts operations to contain the transmission of the Zika virus, residents are urged to cooperate fully with NEA and allow its officers to inspect their premises for mosquito breeding and to spray insecticide to kill any mosquitoes. NEA may need to gain entry into inaccessible premises by force after serving of requisite Notices, to ensure any breeding habitats are destroyed quickly.
To minimise the risk of any spread of Zika in Singapore, it is critical that all of us as a community take immediate steps to prevent mosquito breeding in our homes by doing the 5-step Mozzie Wipeout every alternate day, and protect ourselves from mosquito bites by applying insect repellent regularly.
Zika is generally a mild disease. It may cause a viral fever similar to dengue or chikungunya, with fever, skin rashes, body aches, and headache. But many people infected with the Zika virus infection do not even develop symptoms.
Zika virus infection can however cause microcephaly in the unborn foetuses of pregnant women. We advise residents, especially pregnant women, in the Aljunied Crescent area to monitor their health. They should seek medical attention if they are unwell, especially with symptoms such as fever and rash. They should also inform their doctors of the location of their residence and workplace. Those without these symptoms but who are concerned that they have been infected with the Zika virus should consult and follow the advice of their doctors regarding the monitoring of their pregnancy.
MOH will provide updates on any further developments and our latest public health risk assessments. Singaporeans should refer to MOH’s webpage on Zika (www.moh.gov.sg/zika) for the latest health advisory.