Dengue is transmitted to humans by Aedes Aegypti mosquito, which bites during the day. The virus is contracted from the bite of a striped Aedes Aegypti mosquito that has previously bitten an infected person.

Dengue fever and dengue hemorrhagic fever are acute febrile diseases. It is similar to malaria. But there are some certain differences between dengue and malaria.

Dengue is usually found in only urban areas of developed or developing tropical nations. In its initial stage, it was found in the Tropics. The disease was identified and named in 1779.

A global pandemic began in South-East Asia in the 1950s. Dengue had become a leading cause of death among children in many countries in that region. Epidemic dengue has become more common since the 1980s. By the late 1990s dengue was the most important disease affecting humans after malaria. There being around 40 million cases of dengue fever and several hundred thousand cases of dengue hemorrhagic fever each year.

Spread of dengue cases have also been reported through tourists coming from areas with widespread dengue, such as Tahiti, Pacific, South-East Asia, the West Indies, India and Middle East.

Symptoms

• After being bitten by a mosquito carrying a virus, the incubation period ranges from three to fifteen days. Usually dengue signs and symptoms appear between five to eight days.
• Dengue starts with chills, headache, pain upon moving the eyes and low backache. Painful aching in the legs and joints occurs during the first hours of illness.
• The temperature rises quickly as high as 104 degree F with relative low heart rate and low blood pressure.
• The eyes become reddened. A flushing or pale pink rash comes over the face and then disappears. The glands in the neck and groin are often swollen.
• The palms and soles may be bright red and swollen.
• In more critical condition, there is bleeding with easy bruising, blood spots on the skin, spitting up blood, blood in stool, bleeding gums and nose bleeds. Platelet of blood comes down rapidly.
• Dengue hemorrhagic fever is a specific syndrome that tends to affect children under 10.

Treatment

There is no commercially available vaccine for the dengue or specific medicine or antibiotic to treat it. Patients of dengue must be monitored closely for the first few days. The mainstay of treatment is supportive therapy.

• Oral fluid intake is recommended to prevent dehydration. Supplementation with intravenous fluids may be necessary to prevent dehydration and significant concentration of the blood if the patient is unable to maintain oral intake. Cyanotic patients are given oxygen.
• Vascular collapse requires immediate fluid replacement.
• A platelet transfusion is indicated in rare cases if platelet level drops significantly below 20,000 or if there is significant bleeding. Clinically, the platelet count will drop until the patient's temperature is normal. It is very important to avoid aspirin and non-steroidal anti-inflammatory drugs. These drugs may aggravate the bleeding tendency associated with some of these infections.
• Patients should receive instead acetaminophen preparations to deal with these symptoms if dengue is suspected.

Prevention:

• Primary prevention of dengue mainly resides in mosquito control, i.e. eliminating or reducing the mosquito vector for dengue.
• Public awareness is the most important fact. The most effective step to control mosquitoes is, not to allow water to stand for a long time because it's a fact that Aedes mosquito thrives in clean water.
• Initiatives to remove and dry out standing water have proven useful in controlling mosquito-borne diseases.
• The mosquito breeds in water-filled flower pots, plastic bags, coolers, open water storage tanks and cans round the year. One or two spoon of kerosene or petrol oil can be mixed in cooler water if it is not possible to drain water from the cooler within a week.
• Besides this, personal prevention consists of the use of mosquito nets, repellents, covering exposed skin and avoiding endemic areas. Wear long pants and long sleeves, staying indoors two hours before sunrise and sunset can also help from mosquito bite.
• Government initiatives to decrease mosquitoes also help to keep the disease in check.