Dengue fever: How a mosquito infected millions, and not with malaria

Story highlights

  • Dengue fever is now endemic in more than 100 countries
  • Globally, there are more than 50 million infections each year

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(CNN)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'