Dengue fever is a disease caused by a virus that is transmitted by mosquitoes. It is an acute illness of sudden onset that usually follows a benign course with symptoms such as headache, fever, exhaustion, severe muscle and joint pain, swollen glands and rash.
Dengue strikes people with low levels of immunity. Because it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. However, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed.
Dengue haemorrhagic fever is a more severe form of the viral illness. It is a specific syndrome that tends to affect children under 10 years of age. It causes Manifestations include headache, fever, rash, and evidence of hemorrhage in the body petechiae (small red or purple blisters under the skin), bleeding from nose or gums,black stools , or easy bruising are all possible signs of hemorrhage. This form of dengue fever can be life-threatening and can progress to the most severe form of the illness,dengue shock syndrome.
The virus is contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. The mosquito flourishes during rainy seasons but can breed in water-filled flower pots, plastic bags, and cans year-round. One mosquito bite can inflict the disease.
The virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.
After being bitten by a mosquito carrying the virus, the incubation period ranges from three to 15 (usually five to eight) days before the signs and symptoms of dengue appear.
· Dengue starts with chills, headache, pain upon moving the eyes, and low back ache . Painful aching in the legs and joints occurs during the first hours of illness.
· The temperature rises quickly as high as 104 F (40 C), with relative low heart rate (bradycardia ) and low blood pressure (hypotension). The eyes become reddened.
· A flushing or pale pink rash comes over the face and then disappears. The glands (lymph nodes) in the neck and groin are often swollen.
· Fever and other signs of dengue last for two to four days, followed by a rapid drop in body temperature (defervescence) with profuse sweating. This precedes a period with normal temperature and a sense of well-being that lasts about a day.
· A second rapid rise in temperature follows. A characteristic rash appears along with the fever and spreads from the extremities to cover the entire body except the face. The palms and soles may be bright red and swollen.
Because dengue fever is caused by a virus, there is no specific medicine or antibiotic to treat it. For typical dengue,the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important
Typical dengue is fatal in less than 1% of cases. The acute phase of the illness with fever and muscle aches lasts about one to two weeks. Convalescence is accompanied by a feeling of weakness and full recovery often takes several weeks.
1. The transmission of the virus to mosquitoes must be interrupted to prevent the illness. To this end, patients are kept under mosquito netting until the second bout of fever is over and they are no longer contagious.
2. The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. Empty stagnant water from old tires, trash cans, and flower pots.
3. To prevent mosquito bites, wear long pants and long sleeves. For personal protection, use mosquito repellant sprays when visiting places where dengue is endemic.
4. Limiting exposure to mosquitoes by avoiding stagnation of water and staying indoors two hours after sunrise and before sunset will help. The Aedes aegypti mosquito is a daytime biter with peak periods of biting around sunrise and sunset. It may bite at any time of the day and is often hidden inside homes or other dwellings
5. There is currently no vaccine available for dengue fever.