Malaysia plans to adopt an innovative approach to tackling the spread of dengue fever that could save hundreds of lives and cut massive losses to the economy caused by the mosquito-borne virus. However, some fear the proposed cure may be more harmful than the illness itself.
There has been a 60% surge in the number of fatalities in Malaysia from dengue fever so far this year, with 117 deaths up to the beginning of October and more than 37,000 cases reported. The number of cases worldwide has more than doubled in the past decade, according to the World Health Organisation (WHO).
Dengue fever is becoming the fastest-growing mosquito-born disease in the world, with up to 2.5bn people – 70% of them in Asia – now at risk of contracting the virus, according to the WHO. Carried by the Aedes aegypti mosquito, the virus is now found in some 100 countries, many of which are well outside tropical zones.
The impact of dengue fever on the Malaysian economy is large and growing. Apart from the direct cost of combating the virus and treating those who have become infected, there is the loss of productivity resulting from those suffering from the illness. Estimates put the number of working days lost due to dengue fever at more than 940,000 a year, a significant drain on the economy.
A study by the Indian Institute of Management (IIMA) conducted in 2009 on the comparative costs to economies in the region put the financial burden of the virus on Malaysia at $5.30 per person. With the country’s population now approaching 29m, this would mean more than $153m lost every year, though with the steep rise in the number of dengue fever cases being reported in 2010, this figure could be much higher.
Added to these direct costs is the potential impact that the virus could have on one of Malaysia’s main revenue earners, tourism. Should dengue fever become more prevalent and more cases of foreign visitors contracting the illness be recorded, travelers may think twice about booking a Malaysian holiday.
Those fears may be laid to rest if a project being developed by a joint team of Malaysian and British scientists proves successful. The team has developed genetically modified (GM) male mosquitoes that they want to release into the wild.
According to the plan, the genetically modified mosquitoes will mate with female Aedes aegypti mosquitoes with the resulting larvae weakened due to the genetic modifications bred into them. Few would survive or live long enough to breed.
Though experts involved in the programme acknowledge that it will not eradicate dengue fever, they are confident it will greatly reduce the mosquito pool and make managing the virus easier and less costly.
On October 10, Health Minister Liow Tiong Lai said that laboratory tests were complete and that 2000 to 3000 genetically modified mosquitoes would be released into the wild in two separate states.
“Barring any unforeseen circumstances, the GM anti-dengue mosquito trial will take place by the end of this year,” he said. “On my side everything is clear. Now it’s under the Ministry of Natural Resources and Environment, which will submit the plan to the cabinet for final approval.”
Just one day later though, Prime Minister Najib Razak told an international health conference in Putrajaya that the cabinet would only approve the genetically modified mosquito plan after assessing the outcome and effectiveness of the pilot project.
The government’s increased caution regarding the project is due to concerns within both the scientific community and society at large over any potential risks releasing the modified mosquitoes might entail.
Gurmit Singh, head of the Centre for Environment, Technology and Development believes there are some major downside risks to this ingenious plan.
“Once you release these genetically modified mosquitoes into the environment, you have no control and it can create more problems than solving them,” he said in an interview with Agence France Presse at the end of September. “We don’t know how the genetic flow will be affected. The non-targeted species might be adversely affected and increase the risk of ecological harm. We shouldn't take the risk, it is better to play safe.”
A proposal late last year that a trial release of genetically modified mosquitoes take place on the island of Pulau Ketam, some 30 km south of Kuala Lumpur, prompted strong opposition from locals.
However, the government says that ground-breaking techniques such as the GM mosquitoes need to be explored as expensive attempts to raise public awareness campaigns and spray high-risk areas with insecticide have all failed.