Dengue vaccine

Pediatric Dengue Vaccine Initiative http //www.pdvi.org Program for Appropriate Technology in Health http //www.path.org... 

A large and rapidly growing number of clinical trials (phase I and phase II) evaluating the potential of DNA vaccines to treat and prevent a variety of human diseases are currently being performed ( http // clinicaltrials.gov) however, there is yet no licensed DNA vaccine product available for use in humans. The clinical trials include the treatment of various types of cancers (e.g., melanoma, breast, renal, lymphoma, prostate, and pancreas) and also the prevention and therapy of infectious diseases (e.g., HIV/ABDS, malaria, Hepatitis B vims, Influenza vims, and Dengue vims). So far, no principally adverse effects have been reported from these trials. The main challenge for the development of DNA vaccines for use in humans is to improve the rather weak potency. DNA vaccines are already commercially available for veterinary medicine for prevention of West Nile Vims infections in horses and Infectious Hematopoetic Necrosis Vims in Salmon. 

Viral vaccines less generally available than those listed in die table include Congo Crimean haemorrhagic fever vaccine, dengue fever vaccine, Japanese encephalitis B vaccine, smallpox vaccine, tick borne encephalitis vaccine, and Venezuelan encephalitis vaccine. 

At present, there is no vaccine to protect against dengue. The most effective method of prevention is to eliminate the mosquito that causes the disease. This requires removal of the mosquito breeding sites, a process known as source reduction. Proper disposal of solid waste helps to reduce the collection of water in discarded articles. Other control measures include preventing mosquito bites with screens, protective clothing, and insect repellents in epidemic risk areas, application of insecticide is practiced through an application method known as fogging to decrease the mosquito population. 

Papillomavirus antigen HPV16 LI protein delivery Dendritic cells or muscle, HIV gpl60 protein delivery Dendritic cells, siRNA delivery for dengue virus vaccine Vector expressing leptin Vetor expressing leptin receptor Vector expressing adiponectin... 

Zhang W, Singam R, HeUermann G, Kong X, Juan HS, Lockey RF, Wu SJ, Porter K, Mohapatra SS. Attenuation of dengue virus infection by adeno-associated virus-mediated siRNA delivery. Genet Vaccines Ther 2004 2 8. 

Viral infections are yellow and dengue fevers, caused by flaviviruses transmitted by Aedes aegypti, and Japanese encephalitis, also caused by a flavivirus, which is spread by Culex tritaeniorhynchus All these are controlled by vaccine administration. 

The virus was not, however, isolated until 1928, and a vaccine was first developed by the South African Max Theiler in 1939. Early attempts to eradicate the mosquito by physical means, and later through the use of insecticides like DDT, were only partially successful, and the disease is still endemic in much of West Africa and in South America, but not, surpisingly, in Asia. It has been suggested that this may be due to the fact that it closely resembles the virus that causes dengue fever, which is endemic in all of Asia. They are both arboviruses, which stands for arthropod-borne viruses, are both transmitted via the bite of a mosquito and cause a haemorrhagic illness. Survivors of dengue fever would be expected to have partial immunity (at least) to yellow fever. 

A reduction of the vector population through elimination of larval breeding sites and use of larvicides may be one of keys for the prevention of dengue fever and West Nile fever outbreaks. An increase in the number of WNV-infected patients on the west coast of the USA caused the first domestically imported case in Japan in 2005. Establishment of national countermeasures, such as strengthening of quarantine organizations and vector surveillance around the international air and seaports, is needed in the absence of an effective vaccine. Extensive source-reduction countermeasures of mosquito larvae by local government and individuals must be developed at a community level. 

Ribavirin is an antiviral drug with efficacy for treatment of the arenaviruses and bunyaviruses. Passively administered antibody is also effective in therapy of some viral hemorrhagic fevers. The only licensed vaccine available for VHF agents is for yellow fever. Experimental vaccines exist for Junin, RVF, hantaan, and dengue viruses, but these will not be licensed in the near future. 

No dengue fever vaccine is currently available. However, research is being conducted to develop an effective vaccine for public use, although this is unlikely to be available for another 5-10 years. 

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