Fighting dengue in the 21st century
Aresearch and life sciences company’s proposed solution to dengue fever and Zika sounds like something from science fiction.
Verily, which belongs to Google’s parent company Alphabet, has started releasing in California the first batches of robot-bred male mosquitoes that have been made sterile after being infected with the Wolbachia bacteria. The plan, as explained by the MIT Technology Review (www. technologyreview.com) last week, is to let these boys loose in areas at risk of diseases spread by two types of mosquitoes. Specifically, female Aedes aegypti and Aedes albopictus mosquitoes. You see, only the females bite.
When these potentially lethal females mate with the sterilized mosquitoes, their eggs don’t hatch. Result? Dengue fever, Zika, chikungunya, yellow fever, and any other disease carried by infected female mosquitoes will, in theory, die with them. Verily engineer Linus Upson, in the same MIT story, explained that unleashing sterilized mosquitoes will help communities control mosquito populations “at very, very low costs.”
If you’ve ever seen a family lose a loved one to dengue fever, you will want to root for a potentially effective and low-cost solution. I still remember a visit to Mantuyong in Mandaue City during a dengue fever outbreak 10 years ago. Several families had tents jutting out of their houses, for the wakes that gathered in front of small caskets. Children 10 years old or younger made up half of the 1,145 who had fallen ill with dengue fever in Central Visayas in the first six months of that year.
Yet there are also years when the threat of dengue fever seems to abate. From Jan. 1 to June 3 this year, for example, dengue fever is down compared to last year’s figure in all the regions, except Metro Manila. The count in Central Vi- sayas is 5,790 persons diagnosed with dengue fever, 201 fewer than the tally in the same weeks of 2016. During these years of declining case counts, fewer stories about dengue fever are told, and communities may be lulled into thinking that the threat has been contained.
It hasn’t. In 2007, the World Health Organization (WHO) reported that 50 million suffered from dengue fever each year. This year, that estimate has soared to almost 400 million in at least 120 countries. Aedes aegypti, it turns out, is a well-travelled thing, and dengue fever is increasingly being reported in countries that had not seen it in decades or had never seen it before.
Recent years have ushered in some advances. Last year, Brazil, Mexico, and the Philippines authorized the use of Sanofi’s Dengvaxia vaccine, which is given in three doses. Also last year, researchers at Johns Hopkins Bloomberg School of Public Health said they were working on a single-dose vaccine that could protect against all four strains of dengue fever.
While it’s wonderful to learn about such advances, it’s also important to remind ourselves and our communities that there are easy steps we can take to prevent dengue fever. The Department of Health recommends several practices, starting with searching for and destroying places, like uncovered water containers and used tires, where mosquitoes can breed. Make sure children wear protective clothing (long-sleeved shirts, for instance) if they’re outdoors early in the morning and right before dusk, which are the mosquito’s peak biting times. When a high fever lasts for more than two days, consult a health worker. These are nowhere near as cutting-edge as what more developed countries are doing, but these can save lives while we wait for cheaper vaccines and robot-bred mosquitoes to reach these shores.