National Institute of Virology, Pune, Maharashtra.
Abstracts of the papers presented at the 16th Annual Convention and International Symposium of Indian Virological Society on “Management of Vector-Borne Viruses” at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru-502324, Hyderabad, India, February 7–10, 2006.
Vector-borne viral diseases of humans are popularly called as Arthropod-borne viruses or arboviruses. Arboviruses are the viruses maintained in nature principally, or to an important extent, through biological transmission between susceptible vertebrate hosts by haematophagus arthropods or through transovarian and possibly venereal transmission in arthropods. These viruses belong to 4 families: (i) Togaviruses e.g. Eastern Equine Encephalitis (EEE), Western Equine Encephalitis (WEE), and Venezuela Equine Encephalitis (WEE); (ii) Bunyaviruses e.g. Sand fly Fever, Rift Valley Fever, Crimean-Congo Haemorrhagic Fever (CCHF); (iii) 3. Flaviviruses e.g. Yellow Fever, dengue, Japanese Encephalitis (JE); and (iv) Rhabdoviruses e.g. Chandipura Encephalitis. Natural cycle may involve ?man - arthropod -man e.g. dengue, urban yellow fever; reservoir may be in either man or arthropod vector; in the latter transovarian transmission may take place; animal - arthropod vector - man e.g. JE, EEE, WEE, jungle yellow fever, Kyasanur Forest Disease (KFD); the reservoir is in an animal and the virus is maintained in nature in a transmission cycle involving the arthropod vector and animal; man becomes infected incidentally; or both cycles may be seen with some arboviruses such as yellow fever. The main arthropod vectors are mosquitoes (JE, dengue, yellow fever, St. Louis encephalitis (SLE), EEE, WEE, VEE, etc); Ticks (CCHF, various tick-borne encephalitides etc.) or sand flies (Sicilian sand fly fever, Chandipura etc.). In many cases, the actual reservoir is not known. Some implicated reservoirs are birds (JE, SLE, EEE, WEE), pigs (JE), monkeys (Yellow Fever) and rodents (KFD, VEE, Russian Spring-Summer encephalitis). The diseases caused may be mild like low fever to flue like sickness, or acute encephalitis, hemorrhage etc. Many of these diseases are categorized as emerging and reemerging infections. Understanding of the factors (viral, host or environmental) that cause such emergence and reemergence is a major challenge. In spite of discovery of many important tools detection of etiology for unknown but suspected arboviruses, development of reliable and sensitive diagnosis for patient management and for the management of outbreaks in community remains matter of concern. Newer tools for control and management of arthropod vectors, better and new generation vaccines are very much needed to meet the dream goal - health for all.
