-Vaccine development
There is no commercially available vaccine for the dengue flavivirus. However, one of the many ongoing vaccine development programs is the Pediatric Dengue Vaccine Initiative which was set up in 2003 with the aim of accelerating the development and introduction of dengue vaccine(s) that are affordable and accessible to poor children in endemic countries.Thai researchers are testing a dengue fever vaccine on 3,000–5,000 human volunteers after having successfully conducted tests on animals and a small group of human volunteers. A number of other vaccine candidates are entering phase I or II testing.
- Mosquito control
A field technician looking for larvae in standing water containers during the 1965 Aedes aegypti eradication program in Miami, Florida. In the 1960s, a major effort was made to eradicate the principal urban vector mosquito of dengue and yellow fever viruses, Aedes aegypti, from southeast United States.Primary prevention of dengue mainly resides in mosquito control. There are two primary methods: larval control and adult mosquito control.[citation needed] In urban areas, Aedes mosquitos breed on water collections in artificial containers such as plastic cups, used tires, broken bottles, flower pots, etc. Periodic draining or removal of artificial containers is the most effective way of reducing the breeding grounds for mosquitos.[citation needed] Larvicide treatment is another effective way to control the vector larvae but the larvicide chosen should be long-lasting and preferably have World Health Organization clearance for use in drinking water. There are some very effective insect growth regulators (IGRs) available which are both safe and long-lasting (e.g. pyriproxyfen). For reducing the adult mosquito load, fogging with insecticide is somewhat effective.[citation needed]
Prevention of mosquito bites is another way of preventing disease. This can be achieved by using insect repellent, mosquito traps or mosquito nets.
In 1998, scientists from the Queensland Institute of Medical Research (QIMR) in Australia and Vietnam's Ministry of Health introduced a scheme that encouraged children to place a water bug, the crustacean Mesocyclops, in water tanks and discarded containers where the Aedes aegypti mosquito was known to thrive. This method is viewed as being more cost-effective and more environmentally friendly than pesticides, though not as effective, and requires the continuing participation of the community.
Even though this method of mosquito control was successful in rural provinces, not much is known about how effective it could be if applied to cities and urban areas. The Mesocyclops can survive and breed in large water containers, but would not be able to do so in small containers of which most urban area have within their homes. Also, Mesocyclops are hosts for the guinea worm, a pathogen that causes a parasite infection, and so this method of mosquito control cannot be used in countries that are still susceptible to the guinea worm. The biggest dilemma with Mesocyclops is that its success depends on the participation of the community. This idea of a possible parasite bearing creature in household water containers dissuades people from continuing the process of inoculation, and without the support and work of everyone living in the city, this method would not be successful.
In 2004, scientists from the Federal University of Minas Gerais, Brazil, discovered a fast way to find and count mosquito population inside urban areas. The technology, named Intelligent Monitoring of Dengue (in Portuguese), uses traps with kairomones that capture Aedes gravid females, and upload insect counts with a combination of cell phone, GPS and internet technology. The result is a complete map of the mosquitoes in urban areas, updated in real time and accessible remotely, that can inform control methodologies. The technology was recognized with a Tech Museum Award in 2006.
In 2009, scientists from the School of Integrative Biology at The University of Queensland revealed that by infecting Aedes mosquitos with the bacterium Wolbachia, the adult lifespan was reduced by half. In the study, super-fine needles were used to inject 10,000 mosquito embryos with the bacterium. Once an insect was infected, the bacterium would spread via its eggs to the next generation. A pilot release of infected mosquitoes could begin in Vietnam within three years. If no problems are discovered, a full-scale biological attack against the insects could be launched within five years.
- Potential antiviral approaches
Dengue virus belongs to the family Flaviviridae, which includes the hepatitis C virus, West Nile and Yellow fever viruses among others. Possible laboratory-based modification of the yellow fever vaccine YF-17D to target the dengue virus via chimeric replacement has been discussed extensively in scientific literature. To date, however, no full scale studies have been conducted.
In 2006, a group of Argentine scientists discovered the molecular replication mechanism of the virus, which could be specifically attacked by disrupting the viral RNA polymerase. In cell culture and murine experiments, morpholino antisense oligomers have shown specific activity against Dengue virus.
In 2007 scientists' attenuated virus replication by interfering with activity of the dengue viral protease; subsequently, a project to identify novel protease disruption mechanisms has been launched.
There is no commercially available vaccine for the dengue flavivirus. However, one of the many ongoing vaccine development programs is the Pediatric Dengue Vaccine Initiative which was set up in 2003 with the aim of accelerating the development and introduction of dengue vaccine(s) that are affordable and accessible to poor children in endemic countries.Thai researchers are testing a dengue fever vaccine on 3,000–5,000 human volunteers after having successfully conducted tests on animals and a small group of human volunteers. A number of other vaccine candidates are entering phase I or II testing.
- Mosquito control
A field technician looking for larvae in standing water containers during the 1965 Aedes aegypti eradication program in Miami, Florida. In the 1960s, a major effort was made to eradicate the principal urban vector mosquito of dengue and yellow fever viruses, Aedes aegypti, from southeast United States.Primary prevention of dengue mainly resides in mosquito control. There are two primary methods: larval control and adult mosquito control.[citation needed] In urban areas, Aedes mosquitos breed on water collections in artificial containers such as plastic cups, used tires, broken bottles, flower pots, etc. Periodic draining or removal of artificial containers is the most effective way of reducing the breeding grounds for mosquitos.[citation needed] Larvicide treatment is another effective way to control the vector larvae but the larvicide chosen should be long-lasting and preferably have World Health Organization clearance for use in drinking water. There are some very effective insect growth regulators (IGRs) available which are both safe and long-lasting (e.g. pyriproxyfen). For reducing the adult mosquito load, fogging with insecticide is somewhat effective.[citation needed]
Prevention of mosquito bites is another way of preventing disease. This can be achieved by using insect repellent, mosquito traps or mosquito nets.
In 1998, scientists from the Queensland Institute of Medical Research (QIMR) in Australia and Vietnam's Ministry of Health introduced a scheme that encouraged children to place a water bug, the crustacean Mesocyclops, in water tanks and discarded containers where the Aedes aegypti mosquito was known to thrive. This method is viewed as being more cost-effective and more environmentally friendly than pesticides, though not as effective, and requires the continuing participation of the community.
Even though this method of mosquito control was successful in rural provinces, not much is known about how effective it could be if applied to cities and urban areas. The Mesocyclops can survive and breed in large water containers, but would not be able to do so in small containers of which most urban area have within their homes. Also, Mesocyclops are hosts for the guinea worm, a pathogen that causes a parasite infection, and so this method of mosquito control cannot be used in countries that are still susceptible to the guinea worm. The biggest dilemma with Mesocyclops is that its success depends on the participation of the community. This idea of a possible parasite bearing creature in household water containers dissuades people from continuing the process of inoculation, and without the support and work of everyone living in the city, this method would not be successful.
In 2004, scientists from the Federal University of Minas Gerais, Brazil, discovered a fast way to find and count mosquito population inside urban areas. The technology, named Intelligent Monitoring of Dengue (in Portuguese), uses traps with kairomones that capture Aedes gravid females, and upload insect counts with a combination of cell phone, GPS and internet technology. The result is a complete map of the mosquitoes in urban areas, updated in real time and accessible remotely, that can inform control methodologies. The technology was recognized with a Tech Museum Award in 2006.
In 2009, scientists from the School of Integrative Biology at The University of Queensland revealed that by infecting Aedes mosquitos with the bacterium Wolbachia, the adult lifespan was reduced by half. In the study, super-fine needles were used to inject 10,000 mosquito embryos with the bacterium. Once an insect was infected, the bacterium would spread via its eggs to the next generation. A pilot release of infected mosquitoes could begin in Vietnam within three years. If no problems are discovered, a full-scale biological attack against the insects could be launched within five years.
- Potential antiviral approaches
Dengue virus belongs to the family Flaviviridae, which includes the hepatitis C virus, West Nile and Yellow fever viruses among others. Possible laboratory-based modification of the yellow fever vaccine YF-17D to target the dengue virus via chimeric replacement has been discussed extensively in scientific literature. To date, however, no full scale studies have been conducted.
In 2006, a group of Argentine scientists discovered the molecular replication mechanism of the virus, which could be specifically attacked by disrupting the viral RNA polymerase. In cell culture and murine experiments, morpholino antisense oligomers have shown specific activity against Dengue virus.
In 2007 scientists' attenuated virus replication by interfering with activity of the dengue viral protease; subsequently, a project to identify novel protease disruption mechanisms has been launched.
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