URI_Research_Magazine_Momentum_Winter_2015_Melissa-McCarthy

For a small percentage of affected individuals, the period of febrile relief escalates into a deteriorating condition where plasma leakage occurs, a condition known as Dengue Hemorrhagic Fever. A few may worsen and go into shock, developing a condition known as Dengue Shock Syndrome. Dengue is extremely well adapted for transmission in the human population. The Aedes aegypti mosquito preferentially inhabits large crowded urban areas, making for easy transmission in numbers. Couple population growth and poor sanitation conditions—especially those in underdeveloped countries— and the result is a growing public health issue. “The observation has been that the number of cases of dengue worldwide has risen dramatically in the past several decades,” Rothman says. “This combination of a virus that can make people very sick and can cause very large outbreaks due to these population changes has created the scenario where the number of these cases has been increasing tremendously over time. “It’s a huge public health burden in parts of the world that don’t really have the capability of coping very well. It has a big impact on the health care system. A lot of people get hospitalized and a number of them are children.”

Dengue and its Significance Dengue fever is a mosquito-borne virus transmitted by the female Aedes aegypti , a mosquito partial to tropical environments. The World Health Organization estimates that each year there are approximately 50 million to 100 million cases of dengue virus infection—half a million of which escalate into hemorrhagic fever and about 22,000 cases that result in death 1 . The flu-like symptoms of dengue usually manifest about four to seven days after infection and commonly include high fever, body aches and rash. While symptoms usually will subside after a week, those with repeated infection are at a greater risk to develop blood plasma leakage from the capillaries and go into shock. Rothman is now studying the result of what is believed to be triggered by that immunological phenomenon. Although dengue often is referred to as one virus, there are four serotypes in existence. Infection with one type of dengue virus may allow for the development of immunity to that specific type, but future infection with any of the other three serotypes may still occur. People with antibodies from an earlier dengue virus infection appear to experience a unique immunological response.

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