spreader. a Aedes aegypti mosquitoes, a major carrier of the virus of dengue fever.
Centers for Disease Prevention and Control
Bangkok- scientists have discovered a new type of virus that causes secular pestilence, dengue. The surprising discovery, announced at a major dengue conference here today, is bound to complicate efforts to develop a vaccine against the tropical disease becomes more widespread global threat. But it could shed light on where the pathogen came and if it is becoming a greater threat. The discovery "may change the way we think about dengue virus evolution and emergence," said Duane Gubler, a dengue expert at the Graduate Medical School Duke-NUS in Singapore.
This no vaccine or drug against dengue, which is transmitted by mosquitoes and causes fever and joint and muscle pain, sometimes excruciating pain. patients usually heal on their own, although cases serious need of medical support. sometimes, the disease progresses to the hemorrhagic dengue, a potentially fatal complication in which blood leaks through the vessel walls. a dengue infection confers lifelong immunity to this particular type. But subsequent infection with a second type increases the probability of a serious illness. in this spirit, vaccine developers have sought to protect against four types simultaneously.
this may have gotten more difficult. Fortunately, dengue virus samples screening researchers found a virus collected during an epidemic in the state of Sarawak in Malaysia in 07 they suspected was different from the original four serotypes. They sequenced the virus and found that it is phylogenetically distinct from the other four. Experiments have found that the monkey antibodies produced against the new type differ significantly from those arising from dengue virus already known. "We have discovered and characterized a new dengue serotype," said Nikos Vassilakis, a virologist at the University of Texas Medical Branch in Galveston, today at the Third International Conference on Dengue and dengue haemorrhagic fever.
"They did a great job in the characterization of the virus, and it is convincing that it is distinct from the other four," said Scott Thomas, an expert dengue at the University of California, Davis.
What this may mean for controlling dengue is uncertain. So far, dengue 5 was linked to a single epidemic in humans. Vasilakis suspect it circulates, perhaps among macaques in Sarawak forests. If it spreads, it could make the development more difficult human vaccines. "We do not need another complication in dengue control," says Scott.
Current efforts to control the disease are below. In the discussions here today, researchers from Malaysia, the Philippines and Thailand stated that despite the control programs initiated in the 00s, dengue cases are increasing, although the number of deaths is decreasing thanks to better management of severe cases. "dengue is spreading from urban to rural areas and countries, such as Nepal, where he has not been seen before, "said Samlee Plianbangchang, Regional Director World health Organization in South Asia. the global annual incidence near 30 million cases, is about three times the previously estimated load, the researchers reported in April in Nature .
despite a recent setback in the development of vaccines, Plianbangchang said that projects in the pipeline have researchers "forward to a vaccine in the near future." But he adds that a vaccine will complement, not replace, efforts to contain the dengue mosquito control and public awareness . "Dengue will be with us for many years and could get worse," he said.
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