week4 Meera Senthilingam, for CNN
September 2, 2015
A bite from a single mosquito can result in fever, headaches, and pain. Severe cases can experience a multitude of symptoms including bleeding, shock, organ failure -- and potentially death.
There is no treatment or vaccine and no real means of protecting yourself in countries endemic for the disease.
Though affected countries were once few, today more than 100 harbor the risk of infection -- putting more than half the world's population at risk and resulting in 50 million infections each year.
The infection is Dengue -- formerly known as "break-bone fever" because of the severe joint points it causes -- and it's spread by one of nature's toughest, most versatile mosquitoes -- and it's not the one that spreads malaria.
Coexisting with humans
"It lives, eats and breathes humans" says Duane Gubler, professor of Infectious Diseases at Duke University Medical School, Singapore. Gubler has been working on Dengue control for more than 45 years and founded the Dengue Branch of the U.S. Centers for Disease Control (CDC). He has witnessed the epidemic expanding globally -- through the opportunistic mosquitoes harboring the disease.
"Urbanization provided the ideal ecology for these mosquitoes," says Gubler, referring to the increased density of populations as people flock to cities in search of employment, bringing with them endless supplies of blood for pregnant mosquitoes that need to nourish their eggs.
The villain carrying the Dengue virus is the Aedes mosquito and it comes in two forms: Aedes Aegyti and Aedes albopictus, with the former causing the greatest degree of infection. "They've become highly urbanized and highly adapted to humans," says Gubler.
This species can also carry the virus behind other diseases such as Yellow fever, chikungunya and lymphatic filariasis. But Dengue is the disease that has spread most widely. Their success lies in their ability to bite during the day -- unlike the mosquitoes harboring malaria -- meaning they're difficult to avoid.
What can be done?
"Dengue is one of the diseases we haven't been so successful in tackling or curbing," says Dirk Engels, director of the Neglected Tropical Diseases department at the World Health Organization. "We don't have easy tools to curb the spread of Dengue," he says.
Engels hopes collaborations with pesticide producers could enable better designed programs to kill mosquitoes in the field. Another -- more novel -- strategy is the use of sterilized male mosquitoes to prevent future breeding.
"We've got to prevent transmission," warns Gubler. In his eyes, the tools needed are mosquito control, drugs and a vaccine -- the latter of which is now starting to show promise in terms of protection.
Six vaccines against Dengue have reached clinical trial stages to date and Gubler predicts three of the lead candidates will soon be licensed. Leading the way is pharmaceutical company Sanofi, whose vaccine was shown to cut incidence of the virus by 61% in late-stage trials.
This level of protection is enough to make a difference. "Even though it's only partially effective, they'll have public health utility," says Gubler, who describes the search for a drug to treat the disease as a long road, with no trials for their efficacy reached just yet -- but he's hopeful.
"In the next three to five years we'll see one or more antivirals come on as well," he says.
With drugs and vaccines finally in the pipeline, the disease could be tackled head on -- but not stopped completely.
"We'll never eradicate it," says Gubler. "But if we can use these new tools, we can control it as a public health problem."
http://edition.cnn.com/2015/09/01/health/dengue-fever-mosquito/
Dengue used to be a serious disease in Taiwan. It also caused many people passing away. We all know that if you get Dengue, you will become very painful,which may inclusive of fever, headaches, and so on. So we should be careful. Keeping the potted dry is a good and simple way to prevent it.
回覆刪除According to the survey in 2015, over hundreds of people were diagnosed with Dengue fever. It sounds startling, while there was a tragedy happened. It was reported that a number of persons died from the disease, which is exactly caused by mosquitoes. Everyone was responsible for this incident, that was true. People only emphasized on the containers within their houses ; on the other hand, they payed less attention to the outside surroundings, such as pond and brushwood.
回覆刪除Above all, protecting oneself from the disease is one of the most efficient ways.