10 Facts About Dengue Fever, The Other Disease That S’pore is Fighting Against

If you were on social media nowadays, you’ll quickly realise it’s all about Dee Kosh


And cats.

But what everyone is forgetting is dengue, the virus that has been with us in Singapore for a long, long time.

Here are 10 facts we have gathered about this disease for a dengue 101.

1. 2020 might be the year with the highest number of dengue cases

In 2013, the number of dengue cases reached a record high of 22,170 cases.

Based on the figures from the National Environment Agency (NEA), the number of dengue cases as of 17 August 2020, has surpassed 25,000.

Image: NEA

This means that 2020’s numbers have already exceeded those seven years ago. If this doesn’t sound the alarm bells in you, something is very wrong.

Image: Giphy

2. There are three colours to indicate the severity level of the dengue clusters at your neighbourhood

NEA launched the Dengue Community Alert System where three colours codes (Red, Yellow and Green) are used to differentiate the status level of the dengue cases’ severity.

You might have seen some of those long and wide banners hanging across the railings near bus stops around your vicinity.

What does each colour represent? Well, if the banner shows green, then you can heave a sigh of relief. It means there are no new dengue cases around your hood and the area will be closely monitored for three weeks.

If it’s code yellow, it means the area you live in has less than 10 cases, and it’s classified as a high-risk area.

Code red will be something to note as it means the area has 10 or more dengue cases.

If you are getting worried and would like to know if your area is classified as a dengue cluster, check out this page from NEA’s site.

3. There are more than 300 dengue clusters right now

Similar to us human beings, Aedes mosquitoes like to congregate. In particular, they love spots with favourable conditions for them to breed and bite.

There are 383 active dengue clusters as of 19 August 2020.

Image: NEA

Some of the large clusters include Aljunied Road and Bukit Panjang Ring Road.

On 17 Aug 2020, it was 396 but 13 clusters were closed after no new cases emerged.

A dengue hot spot is defined as a focused area where there are two or more confirmed dengue cases within two weeks, and of 150 meters from each other.

4. There are four types of dengue strains, with DENV-2 being the main strain for most of the dengue cases in Singapore

There are four types of Dengue Virus (DENV) strains and they are all equally harmful.

Based on the Quarterly Dengue Surveillance Data released by NEA and MOH (Ministry of Health), the majority of the dengue cases here are caused by DENV-2.

However, there’s an increase in the number of dengue cases caused by the DENV-3 strain in recent months.

This virus strain has resurfaced again after being dormant for almost three decades.

As DENV-2 was the more prevalent strain, there are already available treatments to cure patients for this.

However, as DENV-3 is relatively new, the immunity for this strain is relatively lower and we are more susceptible to contracting dengue should we be bitten by the mozzie with DENV-3.

5. There are ways to prevent dengue, with celebrities teaching you how to 

Aedes mosquitoes are not a fussy bunch when it comes to their breeding ground.

A small patch of clean and stagnant water about the size of a 20 cent coin is all they need to reproduce.

There are ways to prevent dengue, and all are pretty simple.

NEA has produced a series of clips to educate us on how to remove stagnant water in our homes.

They term it as the ‘Five-step mozzie wipeout’. Check out these videos from Michelle Chia and Mark Lee which teaches you how to wipe out mozzies.

These pesky mosquitoes also love dark corners. Use a mosquito repellent and give these areas a spray.

Places include: Underneath your sofa, behind your curtains etc.

Image: Giphy

6. Fever is also a symptom for dengue 

Similar to Covid-19, one of dengue’s symptoms is the sudden onset of fever for two to seven days. Aside from that, there are a few other signs to watch out for to determine whether you have contracted dengue:

  • Severe headache
  • Joints and muscle pain
  • Skin rashes
  • Nausea and vomiting
  • Bleeding from the nose or gums
  • Skin bruising

You’ll notice that some of the symptoms are very similar to Covid-19, but no matter which one you have, you still have to go see the doctor immediately.

No harm no foul.

7. Mosquitoes Love You When You’re Exercising

Mozzies are attracted to humans with higher temperature or exhales more carbon dioxide, such as when you’re exercising.

That doesn’t mean you should stop exercising completely though. Before heading out, give those exposed skin areas a spray with your repellent.

That should do the trick.

8. Biological Warfare

NEA spearheaded an initiative called Project Wolbachia to reduce the number of female Aedes mosquitoes buzzing around.

Here’s an example of how it works:

Image: Facebook (NEA)

Male mosquitoes carrying the Wolbachia strain is released into the environment.

Female mosquitoes see the males and decided to mate with them.

After intercourse, the Wolbachia strain is injected into the females’ eggs, which ensures that no mosquitoes will hatch from affected eggs.

This project has proven to be a success at Yishun and Tampines. The NEA is already planning to test this out at other areas.

By the way, in case you’re wondering, male Aedes mosquitoes do not bite humans; they survive on plant juices, which is why you can have thousands of them around and they won’t transmit diseases.

They’ll still be irritating, though.

9. Gravitraps

Okay, we’re done with the high-tech tactic so let’s move on to the low(er)-tech one:

See this?

Image: NEA

Basically, what this nifty little thing does is to attract pregnant female Aedes mosquitoes that are looking for somewhere to lay their eggs.

They’ll settle into the Gravitrap and bam, the stick surface will ensure they’ll never come out again.

It also prevents mosquitoes which are recently hatched from leaving the trap.

So make sure you don’t treat them as ashtrays or a mini-dustbin, yeah?

Image: Facebook (Roads.sg)

10. Aedes mosquitoes bite during the day

If you’re wondering why the dengue cases spiked up so much during circuit breaker compared to pre-Covid-19 periods, it’s because Aedes mosquitoes bite during the day.

So with work from home, we’ve created a buffet for these mosquitoes and the perfect breeding environment for them.

That and also because workers are stuck in their dormitories and there’s no one to cut the grass, which led to Aedes mosquitoes breeding like no tomorrow.

Now that the workers are gradually coming back to keep us safe again, we also have to do our part by doing the mozzie wipeout.