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Injection of bacteria could stop dengue fever

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Australian scientists have discovered a cheap and effective method of preventing the transmission of dengue fever, which kills more than 12000 people a year. The researchers showed how female mosquitoes infected with the Wolbachia bacteria passed the bug easily to their offspring, making them all dengue-free. They believe that such infected mosquitoes should be released into the wild, so that the spread of dengue to people may be reduced. In their experiment, the scientists injected the bacteria into more than 2,500 embryos of Aedes aegypti mosquitoes that can spread dengue fever. After they hatched, they were treated to blood meals laced with the dengue virus, and none picked up the virus. The scientists have given two theories as to why the Wolbachia bacteria were able to block the uptake of dengue.  One was that the Wolbachia boosts the mosquito's immune system and protects it from viruses such as dengue. The second was that the Wolbachia competes with dengue for food inside the mosquito, making it harder for the dengue virus to replicate. It should be noted that more than 50 million people in more than 100 countries fall sick and 20,000 die each year from dengue fever. There is no vaccine or specific treatment for the disease. The only method of prevention is to control mosquito populations through eliminating breeding sites and using insecticides.

About Dengue Fever: Dengue fever is caused by one of four different but related viruses. It is spread by the bite of mosquitoes, most commonly the mosquito Aedes aegypti, which is found in tropic and subtropical regions. This includes parts of:

  1. (a) Indonesian archipelago into north-eastern Australia.
  2. (b) South and Central America.
  3. (c) Southeast Asia.
  4. (d) Sub-Saharan Africa. Dengue fever should not be confused with Dengue hemorrhagic fever, which is a separate disease that is caused by the same type of virus but has much more severe symptoms.

Symptoms: Dengue fever begins with a sudden high fever, often as high as 104 - 105 degrees Fahrenheit. A flat, red rash may appear over most of the body 2 - 5 days after the fever starts. A second rash, which looks like the measles, appears later in the disease. Infected people may have increased skin sensitivity and are very uncomfortable.