Dengue (pronounced DENgee) fever is a painful, debilitating mosquito-borne disease caused by any one of four closely related dengue viruses. These viruses are related to the viruses that cause West Nile infection and yellow fever.
Dengue fever is a disease caused by viruses that are transmitted to people by mosquitoes. Dengue fever usually causes fever (high, about 104 F-105 F), skin rash, and pain (headaches and often severe muscle and joint pains). The disease has also been termed “breakbone fever” or “dandy fever” because the unusually severe muscle and joint pains can make people assume distorted body positions or exaggerated walking movements in an effort to reduce their pain.
Dengue fever is endemic in tropical and subtropical areas. Dengue fever is estimated by the World Health Organization (WHO) to cause about 50-100 million infections per year worldwide.
Unfortunately, the disease incidence seems to be increasing. Researchers suggest the surge in dengue fever may be due to several factors:
- Increased urban crowding with more sites for mosquitoes to develop
- International commerce that contains infected mosquitoes, thus introducing the disease to areas previously free of the disease
- Local and world environmental changes that allow mosquitoes to survive the winter months
- International travellers who carry the disease to areas where mosquitoes have not been previously infected
In 2015, an outbreak of dengue fever occurred in New Delhi, the worst in the previous five years. Over 10,000 people tested positive for dengue fever; there have been at least 32 deaths attributed to this outbreak. State-run hospitals were so overcrowded that patients were sharing beds. An independent group (Brandeis University) suggests the actual numbers of people in India with dengue are vastly under-reported.
Symptoms of Dengue Fever
Symptoms, which usually begin four to six days after infection and last for up to 10 days, may include
- Sudden, high fever
- Severe headaches
- Pain behind the eyes
- Severe joint and muscle pain
- Skin rash, which appears two to five days after the onset of fever
- Mild bleeding (such a nose bleed, bleeding gums, or easy bruising)
Sometimes, symptoms are mild and can be mistaken for those of the flu or another viral infection. Younger children and people who have never had the infection before tend to have milder cases than older children and adults. However, serious problems can develop. These include dengue hemorrhagic fever, a rare complication characterized by high fever, damage to lymph and blood vessels, bleeding from the nose and gums, enlargement of the liver, and failure of the circulatory system. The symptoms may progress to massive bleeding, shock, and death. This is called dengue shock syndrome (DSS).
How Is Dengue Fever Transmitted?
The viruses are transmitted from Aedes aegypti and Aedes albopictus mosquitoes to humans in a viral life cycle that requires both humans and these mosquitoes. There is no human-to-human dengue fever transmission. Once a mosquito is infected, it remains infected for its life span. A human can infect mosquitoes when the human has a high number of viruses in the blood (right before symptoms develop). The viruses belong to the Flaviviridae family and have an RNA strand as its genetic makeup. Virologists term them dengue virus types 1-4 (DENV 1-4). All four serotypes are closely related. However, there are enough antigenic differences between them that if a person becomes immune to one serotype, the person can still be infected by the other three serotypes.
Is Dengue Fever Contagious Or transmittable?
Dengue fever is not contagious or transmittable; it will not spread from person to person. Dengue fever viruses require a vector, a mosquito, that allows the virus to mature within the mosquito before the mosquito can effectively transfer the viruses to humans during a blood meal.
How Long Does Dengue Fever Last?
Symptoms of infection usually start about four to 15 days (the incubation period is typically four to seven days) after a mosquito bite transfers the viruses to the human. In most instances, the disease lasts about three to 10 days, although a few patients’ symptoms may last longer. During the incubation period, large amounts of the virus are present in the person’s blood just before the person becomes symptomatic; this is when a mosquito that may be uninfected can pick up viruses that can be transferred to other humans.
Home Remedies for Dengue Fever?
Papaya leaf extract has been used to help increase platelet levels in some patients with dengue fever, but researchers caution that definitive studies are not yet available that confirm the utility of this treatment. Patients should consult their doctors before using this remedy.
What Are Dengue Fever Complications?
The complications of dengue fever are usually associated with the more severe forms of dengue fever: hemorrhagic and shock syndrome. The most serious complications, although infrequent, are as follows:
- Bleeding (haemorrhage)
- Low platelets
- Low blood pressure (hypotension)
- Slow heart rate (bradycardia)
- Liver damage
- Neurological damage (seizures, encephalitis)
Diagnosing Dengue Fever
Dengue fever testing is used to determine whether a person with symptoms and recent potential exposure to dengue have been infected. The infection is difficult to diagnose without laboratory tests because symptoms may initially resemble other diseases, such as malaria. 3 types of testing are available:
- NS1 antigen tests should be conducted within the first five days of the onset of symptoms and IgM-Elisa test after five days
- Antibody tests: these tests are primarily used to help diagnose a current or recent infection. They detect two different classes of antibodies produced by the body in response to a dengue fever infection,IgG and IgM. Diagnosis may require a combination of these tests because the body’s immune system produces varying levels of antibodies over the course of the illness. IgM antibodies are produced first and tests for these are most effective when performed at least 7-10 days after exposure. Levels in the blood rise for a few weeks, then gradually decrease. After a few months, IgM antibodies fall below detectable levels. IgG antibodies are produced more slowly in response to an infection. Typically, the level rises with an acute infection, stabilizes, and then persists long-term. Individuals who have been exposed to the virus prior to the current infection maintain a level of IgG antibodies in the blood that can affect the interpretation of diagnostic results.
- Molecular testing (polymerase chain reaction, PCR): this type of test detects the genetic material of the dengue virus in blood up to 5 days after symptom onset (fever).
Consult your doctor for diagnosing dengue fever and never start self-medication or home remedies. FAQ
NS1 Antigen Test ₹750.00
Dengue IgG IgM Antibodies Test ₹1500