A month has passed since news of the first-locally transmitted Zika cases in Singapore. Since then, commendable efforts have been taken by mall and facilities managers, restaurants, hotels, offices, and individuals, who have increased mosquito management services at their premises to protect their employees, colleagues, and loved ones. How successful have these efforts been? What is the current status of the Zika spread and control?
The Zika Situation Locally
As of 30th September, there has been a total of 398 local Zika cases, 16 of whom were pregnant women (1). Although the numbers spiked sharply in the first week of discovery of local transmission, the situation now has improved. 2 Zika clusters have been closed - the Bishan cluster on 19 September, and the Bedok North cluster on 30th September, after not reporting new cases for two consecutive weeks (2). Senior Minister-of-State Amy Khor praised this, saying it was ‘only possible because the community played its part in staying vigilant and took care to prevent mosquito breeding at their premises’ (Channel NewsAsia, 29 September 2016). Out of the 7 Zika clusters, only 1, Aljunied Cluster, has reported new cases in the past 2 weeks.
The number of new Zika cases in Singapore has been decreasing. Graph retrieved from http://graphics.straitstimes.com/
Overall, the situation seems to be substantially improving, though this is no reason to slacken our efforts inefficient mosquito control, and rigorous removal of breeding spots, so as to mold the number of Zika cases into a decreasing trend.
What’s going on in Southeast Asia
The first case of Zika-linked microcephaly in Southeast Asia was confirmed in Thailand on 30th September. Thailand has had one of the highest Zika infections in Southeast Asia, with 300 cases since January, 25 of whom were pregnant women (3). Amid rising fears, Thai health officials are assuring the public that this is yet to be an epidemic, and are stepping up efforts in mosquito eradication.
On the same day, the U.S. Centers for Disease Control and Prevention issued a travel advisory, encouraging pregnant women to postpone travel plans to 11 Southeast Asian countries: Brunei, Myanmar, Cambodia, Indonesia, Laos, Malaysia, Maldives, Philippines, Thailand, Timor-Leste and Vietnam (4). Thankfully, Singapore did not make the list. Nevertheless, caution should be taken when traveling to these countries.
Travel Advisory issued by US Centre for Diseases Control and Prevention. Image retrieved from http://www.huffingtonpost.com
Global Status of Zika
The latest update by the World Health Organisation on 22 September stated that there are now 61 countries affected by Zika. In the past week, Saint Kitts and Nevis (Caribbean islands) had Zika cases for the first time, and Guatemala reported its first Zika-linked microcephaly case. The number of Zika cases worldwide thus seems to be increasing. However, one good news is that since the Paralympic Games ended in Rio on 18 September, there has been no notification of Zika spread through this event as yet (there was no reported spread due to the Olympics, either) (5, 6). Nevertheless, WHO still advises those who have been to Rio to consider sexual abstinence for at least 6 months upon return.
In sum, despite new locations still being hit by Zika globally, Singapore is handling the situation quite well. Efforts should remain conscientious, and premises that do not have a comprehensive mosquito management programme should not take the improving situation for granted. Ideally, misting should be conducted weekly at external areas (as a mosquito takes about 3 - 8 days from larva to adult), especially if there is thick vegetation or widely landscaped areas (that provides many potential breeding spots). Besides misting, Zone Treatment can also serve as a physical barrier, preventing mosquitoes from entering indoors.
In ORIGIN Mozzie Free Zone Treatment, external walls are coated with an adulticide, to deter mosquitoes from entering indoors. It cannot be emphasised enough that all stakeholders - health agencies, facilities managers, and pest management vendors, and individuals - work hand-in-hand to continue bringing our local Zika numbers down.