Dengue Specialist Doctor In Mumbai The Dengue virus ( DENV ) complex comprises of four distinct types, designated as DENV types 1 through 4. The transmission of the DENVs are maintained through a human – mosquito – human cycle involving mosquitoes of the genus Aedes. The principal vector for the transmission of the DENVs are Aedes aegypti. An uninfected Aedes mosquito may acquire the virus after feeding on an infected individual. Once infected, mosquitoes carry the virus for their lifespan and remain infective for humans. They are an ideal vector for dissemination of the virus. They typically breed in or close to houses, laying eggs in both man - made and natural water containers. They are preferentially daytime feeders, and their feeding episodes often go unnoticed. They are easily interrupted in their feeding and often move to another host, frequently taking multiple blood meals in a single breeding cycle. Thus, an infected Ae. aegypti mosquito may transmit a DENV to several individuals within the household. Ae. albopictus mosquitoes are also a competent vector for the transmission of the DENVs, however they do not feed on humans as frequently as Ae. aegypti. Both of these vectors are also competent vectors for transmission of zika and chikungunya viruses. The infections in human may be asymptomatic or present with a broad range of clinical manifestations including a mild febrile illness to a life threatening shock syndrome. The symptoms typically develop between 4 and 7 days after the bite of an infected mosquito. There are three phases that can be seen in the setting of DENV infection, a febrile phase, a critical phase, and a recovery phase; however the critical phase is not seen in all categories of infection. In 2009, the World Health Organization introduced a revised classification scheme consisting of the following categories: dengue without warning signs, dengue with warning signs, and severe dengue. The common presentations include fever, nausea / vomiting, rash, headache, eye pain, muscle ache or joint pain. The warning signs include abdominal pain, persistent vomiting, bleeding, lethargy or restlessness. The severe dengue presents with shock, severe bleeding and severe involvement of organs like liver, kidney or brain. This progression to severe dengue can be many times prevented with timely intervention and guidance of a specialist. Between days 3 and 7 of the illness, the complications or worsening generally happen. The complications include low blood pressure, very low platelets and severe involvement of liver, kidney, heart or brain. The patients should seek advice of a specialist at the earliest symptoms of the infection, rather than wait for the things to turn for worse. During the first week of illness, the diagnosis of DENV infection may be established via detection of viral antigen nonstructural protein1(NS1). Immunoglobulin (Ig) M antibody can be detected as early as four days or more commonly after a week after the onset of illness. The counselling from a specialist is must, so that appropriate investigations can be done by the patients. There is no direct antiviral therapy available against the DENVs. The treatment is supportive, which largely consists of maintaining adequate hydration. The early recognition of progression to severe disease and patients at increased risk for severe disease is essential, hence the opinion from a specialist matters. These subset of patients require more aggressive therapy. The unnecessary platelet transfusions should be avoided at all costs. The approaches for the prevention of DENV infection and disease include mosquito control, personal protective measures, and vaccination. It has been found that insecticide spraying in response to dengue outbreaks is not highly effective, since A. aegypti mosquitoes frequently breed inside houses. The measures to reduce breeding sites of the mosquitoes like discarded tires and other containers, have shown some promise. The control of mosquito larvae is also one of the strategy that has been tried in some places. When a person is outside during the day, individuals should wear clothing that reduces the amount of exposed skin and should use an effective mosquito repellent. The vaccine against DENV is currently unavailable in India, as follow – up analyses of the vaccine trials, done in countries where the vaccine is available, found significant limitations of the vaccine.