KUALA LUMPUR, March 10 — Twenty years have gone by since Chris Low, 40, got dengue fever.
What scares him is he can still “feel” and remember the symptoms today.
“I remember having a very high fever one day, my head was pounding, it felt as if it was about to explode.
“By the time I went for a check-up, the doctor didn’t say much, I wasn’t even asked if I wanted to be admitted into the hospital… instead I got a drip needle stuck to the back of my hand immediately.
“All I heard was, ‘yes it’s dengue’,” Low said.
While Low was in the hospital, he was told that there was a dengue outbreak.
“It wasn’t a pleasant experience. I remember my nose bled very frequently, and one day it didn’t stop bleeding for almost an hour.
“I couldn’t eat, and I can still recall the nurse coaxing me to at least eat a piece of bread. My body was in a very confused state — I felt like vomiting all the time, I was hungry but I couldn’t eat, my gums hurt and my joints hurt too.
“I also had body shivers while my fever was running,” Low said.
When he was finally discharged, he said he could barely read a text message on his mobile phone because it gave him a severe headache, on top of which he could barely walk a straight line.
“I still recall that feeling until today, and that is my warning to my friends… that if ever they feel this way, they should get themselves checked for dengue immediately,” he added.
Low may have recovered from dengue fever, but he received a lifelong “souvenir” from the whole episode — a gastrointestinal condition.
Since that first time he came down with dengue, he caught it twice more — thankfully a milder strain.
Because of his medical history, Low is extremely cautious and tries to keep up with the updates on the Aedes mosquitoes and the development of the dengue virus.
Aedes aegypti mosquito breeding process. — Picture by Hari Anggara
How harmful is the dengue virus?
The idea of a mosquito bite causing a fatality may sound bizarre, but it remains a fact that the dengue virus can lead to death if it is not treated properly especially in children, elderly and people with weak immune systems.
Fever is not the only noticeable symptom. Along with that comes other illnesses or complications including severe headache (migraine-like), joint and muscle pain (this includes gum pain), skin rash (looks similar to heat rash), nausea and vomitting (appetite loss) and pain behind the eyes.
In most cases, a person with dengue fever recovers in one to two weeks, but there are also some who experience severe illnesses that eventually lead to death.
For example, there is the Dengue Hemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS).
Some signs of DHF include blood in the nose, gum, vomit or stool, plasma leakage, leading to organ damage or shock and eventually death.
As for DSS, signs include blood pressure dropping dangerously low, organ failure, leading to death.
There are also long-term effects that can occur such as prolonged fatigue and weakness, liver damage, gastrointestinal infection and increased risk of complications.
So, Aedes mosquitoes are still in Malaysia?
Yes, they are.
In January, Deputy Prime Minister Datuk Seri Ahmad Zahid Hamidi was reported confirming that there was an increase of 17 per cent in deaths from dengue cases — that is from 100 in 2023 to 117 in 2024.
While the number of cases dropped in 2024 by 0.6 per cent, dengue still remains a concern as the number of cases fluctuate due to several factors including the tropical climate and mosquito behaviour.
Since the Aedes mosquitoes are still around (and staying), what has the government been up to with containment efforts?
Ongoing fogging exercise carried out in high-risk areas. — Picture by Farhan Najib
Still fogging regularly
The National Dengue Prevention and Control Programme is ongoing, and that includes regular fogging at high risk areas and conducting awareness programmes such as the 10-minute Aedes search programme to check on mosquito breeding spots weekly.
Households today can even carry out their own prevention exercises and among other measures, they can use chemicals like temephos (brand name Abate which is easily available) in areas where they discover mosquito larvae.
Introduction of Wolbachia mosquitoes
In 2017, Wolbachia-infected mosquitoes were introduced into Malaysia through a pilot project under the Health Ministry through its research arm, Institute of Medical Research (IMR).
The release of Wolbachia-infected mosquitoes in Malaysia was undertaken to render wild mosquito populations unable to transmit not only dengue, but Zika or chikungunya virus.
Wolbachia or Wolbachia pipientis is a type of bacteria that can be found in insects and proven to be harmless towards humans, animals and the environment.
The concept was that the wild female mosquitoes will be unable to have any offspring after mating with male Wolbachia-infected mosquitoes.
Initial trials were conducted in Selangor and later expanded to other high-risk dengue areas including Kuala Lumpur, Melaka and Penang.
Introduction of Wolbachia-infected mosquitoes in Malaysia as part of the Health Ministry’s containment efforts to reduce the spread of dengue virus. — Picture by Hari Anggara
By 2023, the Health Ministry in news reports said the programme had been scaled up significantly and showed effectiveness in suppressing the dengue virus.
The research experiment was also conducted in nine other countries including Singapore, Brazil, India and the United States, but only Malaysia and Australia have carried out operations to reduce the population of mosquitoes carrying lethal viruses.
Fines imposed on mosquito breeders
Local councils were given the authority to issue fines up to RM500 or more to property owners who are found to “allow” mosquito breeding.
Construction sites and factories can face penalties if they do not follow anti-dengue measures.
Advanced surveillance and technology
The eDengue system was introduced in 2009 and made available a surveillance system to track real-time dengue cases enabling more efficient case management, outbreak detection and later upgraded in 2016 to record deaths by the dengue virus.
This system integrates with the iDengue system which provides real-time data on dengue cases hotspots.
These trends are then reported to the Health Ministry on a weekly basis whereby the ministry will monitor changes in the virus in the country.
Is there a vaccine for dengue?
In February 2024, Malaysia’s Drug Control Authority (DCA) approved the Qdenga Dengue vaccine through a conditional registration.
Qdenga works to prevent the dengue disease containing dengue stereotypes 1, 2, 3 and 4.
This vaccine contains attenuated versions of the four virus stereotypes, whereby they cannot cause disease but they “teach” the immune system to defend the body against the virus.
When one receives the vaccine, the immune system identifies the attenuated stereotypes as foreign and makes antibodies against them.
So when a person with the vaccine is later exposed to the virus, the immune system recognises it and makes many more antibodies which then neutralises the virus before it can cause dengue disease.
Although the vaccine is still new, those who are age four and above regardless of whether they were previously infected by the virus can take this vaccine.
Health experts have been calling for higher fines imposed on those who allow mosquito breeding, citing RM500 as too low, especially for commercial properties.. — Istock.com pic via AFP
Calls for better prevention measures
However, despite these efforts the government rolled out throughout the years, there are some calls for further improvement in the prevention of dengue.
Among others, health experts have been calling for higher fines imposed on those who allow mosquito breeding, citing RM500 as too low, especially for commercial properties.
As for the efficacy of the Wolbachia mosquitoes, health experts are suggesting a wider geographical coverage since the programme was only carried out in selected areas.
Although dengue fever is an age-old disease, more than 123,000 cases were recorded in 2022. There was a drop in 2023 but as of August 2024, a total of 92,420 dengue cases were recorded marking an increase from 75,928 cases during the same period in 2023.
This suggests that awareness programmes are still much needed nationwide as symptoms presented have varied throughout the years.
Natalia Aziz, 37, a former dengue patient told Malay Mail that she did not suspect the virus at all as she did not experience any headache or body aches.
In fact, among her peers, dengue fever was not taken seriously but after being infected by it, she agreed that while there was not a outbreak in her housing area, the disease should not be neglected.
“I did have a fever for a few days, followed by vomiting.
“I initially tested negative, but I was told to go back on the fifth day, and that was when we noticed that my platelet count was dropping.
“I tested positive on the sixth day, but I still was not admitted until my vomit had blood flecks on the seventh day… I was admitted via emergency,” she said.
