DENGUE fever has been on the increase in the country. Attributable to the weather, the switch from rainy to hot season has speeded up the carrier’s breeding cycle, which in turn has led to its increased activity. Spread by the mosquito Aedes aegypti, a species especially suited to the urban environment as it feeds during the day, the disease is preventable only through fogging, which kills the adults, but leaves the larva and pupa undisturbed. The only recourse is to deprive these mosquitoes of a breeding ground, and that requires ensuring that no still bodies of water, large or small, are found in the immediate vicinity. Because dengue has been rampant in recent years and public education campaigns have been numerous, few can claim ignorance. Obviously, therefore, the increase in incidence can be attributed to apathy on the part of Malaysians.
So steep is the rise of reported cases in the first six months of this year — almost quadrupling — that the government has set up a task force headed by the deputy prime minister to implement preventive measures nationwide. Challenging the task force is the attitude of Malaysians, be they households or the local authorities. Laws intended to prevent the spread of the disease exists, but experience suggests that enforcement might be wanting. The number of deaths this year as of June 21 is 82, up from 25 in the same period last year. Some hospitals have reportedly run out of beds and are forced to turn away patients. What is of concern to the authorities is the shift in the dominant virus serotype circulating. The possibility of a new strain of the dengue virus is being investigated. Nevertheless, even if a new strain is identified, the preventive method at hand remains traditional and does not eliminate the disease
at source.
Naturally, a more effective method of eliminating the disease, given its very specific vector, has been actively pursued. Spread only by the female of the species that does not cross-fertilise with other species of mosquitoes has provided clues on how best to deal with the problem. The obvious solution is to end the species altogether. In 2011, tests were carried out by Malaysia’s Institute for Medical Research on a technology developed by the company, Oxitec Limited, which commercialises leading-edge technology developed by Oxford University in the United Kingdom. Some 6,000 genetically engineered sterile male Aedes mosquitoes were released into a restricted uninhabited area of Sabah to mate with the wild females. This should, if at all, produce larva that are too weak to survive and in this way will ultimately end the species. Of course, environmentalists are wary of upsetting the balance of the ecosystem, but a similar study carried out in the Grand Cayman in 2010 showed that a reduction rate of as high as 80 per cent can be achieved.