By Joachim Ng
Is Malaysia experiencing the start of a dengue epidemic that will kill hundreds, or worse a dengue pandemic that will kill thousands around the world? The Aedes aegypti mosquito that carries the virus is experiencing a massive population boom with an ever-worsening heatwave that is a manifestation of climate change.
Dengue fever has claimed six lives in Perak up to June 22, with five from the Kinta district and one from Manjung district. Nationwide, 48 have died this year up to June 10.
“This number of deaths shows a significant increase compared to zero deaths reported for the same period in 2023,” Chairman of the Perak Committee on Human Resources, Health, Indian Community Affairs, and National Integration, A. Sivanesan, said in a statement received by Ipoh Echo the same day.
Dengue cases have risen to 4,410 cases — a 161.8 percent jump compared to 2,726 cases last year, Sivanesan disclosed. Last year too, dengue cases soared by 174.7 percent between January and October compared to the same period in 2022.
Nationwide up to June 10, a total of 67,775 cases were recorded whereas last year it was 51,331 and in 2022 the total was 20,194. This is a 32% jump over last year and a 236% jump over 2022. The Health Ministry also disclosed that there were 48 dengue deaths for this year’s period compared with 37 deaths for the same period last year.
In just one week early this year, Kuala Lumpur saw dengue cases soar by 72.8 percent over the same period in 2023. In the first five months of 2024, Selangor registered 33,754 cases — a 38% jump over the same period last year, a 209% jump over the same period in 2022, and a 462% jump over 2021. Johor recorded 214 cases in just one week from April 29 to May 5.
Are we nearing a crossover point where a pandemic begins? The dengue virus has exploded across South America, with 3.8 million people in Brazil catching it in the first four months of last year. Argentina saw 129 deaths out of 180,500 cases during its recent summer. In the first eight weeks of this year, Peru saw total cases climb to 31,300 — double the figure in the same period last year.
The World Health Organisation had last year warned of a looming dengue threat to southern United States, southern Europe, and more parts of Africa with the human-loving Aedes aegypti mosquito vastly expanding its numbers and reaching new places beyond its traditional strongholds in Asia as it keeps pace with the human population boom over recent decades.
Daytime urban temperatures in Malaysia are now hitting 35C and in this heat the dengue virus incubates and replicates faster in the mosquito.
This means it can transmit the virus earlier in its life. Higher temperatures require the mosquito to feed more often, and dense urban populations are a great source of human blood. So, they come out to bite you earlier and stay around longer.
Mayor Datuk Rumaizi Baharin has explained that the “alternating and persistent hot, dry, and rainy weather patterns have led to a heightened risk of Aedes mosquito density, contributing to the spread of dengue cases.”
Although nature has also provided a natural birth control mechanism in the Wolbachia virus-blocking bacterium that interrupts transmission of dengue, over-reliance on it poses a severe risk.
Malaysia has been releasing Wolbachia-infected Aedes mosquitoes into dozens of dengue hotspots since 2019 and this population control technique has proven to be highly successful. When a female Wolbachia-infected mosquito breeds, it passes the bacterium to its offspring ensuring further interruption of the dengue virus transmission.
As billions of Wolbachia mosquitoes need to be released to overwhelm the non-infected mosquitoes, overuse may result in the Aedes mosquito mutating and becoming resistant to the Wolbachia bacterium.
In a few Southeast Asian countries such as Cambodia, more than 90% of the Aedes aegypti mosquitoes have a combination of mutations that make them super-resistant to insecticides. Insecticide levels that previously would kill almost 100% of mosquitoes can now kill only 7%.
A radical solution is to exterminate the Aedes mosquito by genocidal killing methods. This bypasses the need to eliminate breeding places but may result in the growth of a new threat: the animal-loving anopheles gambiae mosquito that carries malaria. As humans keep encroaching into the natural habitats of malarial mosquitoes through logging, agriculture, and new settlements, the anopheles takes a stronger liking to human blood and may eventually start breeding in cities.
Kelantan recorded 215 cases last year, an increase of 84% over the previous year. There were no human malaria infections nationwide from 2018 to 2021.
There are two types of malarial transmissions: indigenous transmission in a geographic area populated by anopheles gambiae, and the human victims are usually foresters and hunter-gatherers; zoonotic transmission of the malaria-causing Plasmodium Knowlesi parasite from monkeys to humans occurring with deforestation, and the consequent spread of logging, agriculture, and settlements.
The best advice has always been: Don’t let Aedes breed in your house and your neighbourhood. And this advice has always been ignored. What is missing is the education and public relations effort.
As discussed in many of this column’s previous articles, city councils have a large scope of responsibilities and cannot micromanage neighbourhoods. The new Indian state of Telangana (ten years old last June) bears testimony to the advantages of decentrallsed governance. Neglected when it was part of Andhra Pradesh, Telangana saw improved governance with autonomy and its GDP rose from 4.1% to 4.8%.
Malaysia can replicate Telangana’s success by taking it one step further: devolving power from local councils to neighbourhoods. The job of tackling Aedes is best handled by legally empowered neighbourhood committees. They can be given a budget for printing of A3 dengue prevention flyers. Volunteers can then be asked to put a flyer into every mailbox for every household and business premise.
Why this old-fashioned method of education that everyone looks down on today? That’s because a printed flyer is more likely to be read than anything on television or social media where there are myriad products and channels vying for attention. The printed flyer is a standalone, and so it stands out.
Two superhero examples – both set in Johor – demonstrate the hands-on willingness of dedicated residents to fight dengue. Panjang as usual goes about patching road potholes but eight years ago he started picking up garbage from the clogged drains of back lanes in city housing estates. He has pulled out mattresses, bricks and used clothes.
Another superhero is Salmiah, who turned over a new leaf after her two sons fell victim to dengue. Ever since then, she has been diligently helping to keep her neighbourhood drains free of rubbish that blocks water flow.
More residents will come out to lend a hand if only neighbourhood committees can be formed through law. These committees should be empowered to oversee the work of cleaning contractors so that all drains are well maintained, grasses are trimmed and free of lallang, and walking paths are kept litter-free.
What is the role of city councils? Enforce dengue prevention by regular inspections of neighbourhoods and issuing summonses to offenders.
Malaysian households are generally unaware how smart the Aedes mosquito has become. If you keep a big pail of stored water in the bathroom without covering it, a superficial check will mislead you into thinking that it’s all clear. But larvae no longer appear on the water surface as that makes them easily detectable: they now reside at the bottom of the pail, and you can only see them with a powerful torch.
Remember that any drop of stagnant water that fails to dry up within three days is enough for an Aedes mother-to-be.
Top neighbourhood breeding locations that city councils must crack down on include construction sites; unfinished house renovations; abandoned houses; vacant land; disused carpark buildings; roadsides, road dividers; derelict cars left by roadsides.
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Disclaimer: The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of Ipoh Echo
