Update On Chikungunya Fever Situation(3)

12 Sep 2008

Current overall situation

An additional 22 cases of Chikungunya fever (including 11 imported) have been identified since the last update.  As of 11 September 2008, a total of 200 cases were notified this year. Of these, 97 were imported cases with history of travel to Johor (77 cases) and other states of Malaysia (11 cases), Indonesia (four cases), Sri Lanka (two cases), India (two cases) and the Maldives (one case). The remaining 103 were locally acquired infections which probably occurred at 22 separate locations, including 41 cases in Kranji Way, 17 from Sungei Kadut, 13 from Little India, six from Lim Chu Kang Lane 2, five from Pasir Panjang Wholesale market, three from Mandai Estate and two from Seletar Farmway.

Most of the patients have since recovered except for a few recent cases who are still hospitalised.

New imported cases

Of the 11 imported cases, nine were Singapore residents who had history of travel to Malaysia [Johor(6), Malacca(3) ] prior to their onset of illness. The remaining two imported cases were Malaysians who had travelled back to Malaysia prior to their onset of illness. 

New local cases

Of the 11 local cases, two are part of a new cluster at Seletar Farmway, seven are linked to existing clusters, while the remaining two are isolated cases that occurred in separate locations.

New cluster at Seletar Farmway – Two retirees (males, aged 60 and 69 years), developed symptoms on 6 Sep and one of them was subsequently admitted to hospital. Both of them had been to Seletar Farmway prior to onset of their illness. Investigations are in progress.

Cases linked to existing clusters

Kranji Way - Two more cases who worked and stayed at Kranji Loop had onset of illness on 31 Aug and 3 Sep. This brings the total number of cases in the cluster to 41.

Sungei Kadut - Three more cases had been in the vicinity of Sg Kadut fell ill between 10 Aug and 8 Sep. This brings the total number of cases in the cluster to 17.

Mandai Estate – Two more workers in the area developed symptoms on 5 Sep. This brings the total number of cases in the cluster to three.

Other local cases

Two additional separate cases were identified at Crawford Lane (a 64 year-old male) and Mei Ling Street (56 year-old female) They developed symptoms on 25 Aug and 29 Aug. All their family members were well.

Updates on vector control operations by the National Environment Agency (NEA)

Intensive vector control remains the primary control to prevent spread of Chikungunya. Upon notification by the Ministry of Health (MOH), the NEA has been carrying out vector control operations in and around the cases’ residential premises, including their work places and places that they normally frequent. Mosquito breedings that are detected during NEA’s inspections are destroyed immediately and enforcement actions have been taken against owners/occupiers of premises found with mosquito breedings to ensure that they take the necessary measures to keep their premises free of further mosquito breedings.

Updates on new sporadic cases:

So far, 4 premises in the Mei Ling Street area have been found with mosquito breedings while none has been detected in the premises inspected in the Crawford Lane area. The NEA is continuing with its inspection in the two vicinities.

Updates on existing clusters:

All premise owners are urged to check their premises daily to remove any stagnant water that may breed mosquitoes.  Orders were also served on premises owners to render their premises non-conducive for the breeding of mosquitoes.  Under the law, non-compliance with such orders can result in a maximum fine of $50,000.

Ministry’s Advice to the Public

In the absence of a vaccine, and the presence of the Aedes mosquito vector, Singapore remains vulnerable and receptive to the introduction of Chikungunya outbreaks. It is likely that cases will continue to occur as long as situations in neighbouring countries do not improve. The full support and cooperation of the community and every stakeholder is needed to minimise the likelihood of the disease becoming endemic in Singapore.

The Ministry advises persons who develop symptoms of chikungunya which include fever, joint pain and rashes to consult their doctors immediately.

Chikungunya fever, like dengue fever, is a mosquito-borne disease and the best way to prevent chikungunya fever is to take precautionary measures against mosquitoes and prevent their breeding. Persons infected with chikungunya fever should be isolated from further mosquito bites so as to reduce the risk of further transmission of the virus.

Ministry of Health

National Environment Agency

12 September 2008