Overview
Dengue fever, also known as breakbone fever, is a mosquito-borne disease transmitted to humans through an infected mosquito's bite. In the tropics and sub-tropics, dengue is a leading cause of illness. About 100-400 million dengue cases are reported globally every year.
Dengue Fever Causes
- Dengue fever is a viral infection that spreads to humans through the bite of a female mosquito, Aedes aegypti.
- Dengue virus belongs to the flaviviridae family, and there are four closely related viruses that cause dengue ( Dengue virus 1,2,3,4). For this reason, you can be infected with dengue as many as four times in your lifetime. You may be immune to a specific dengue virus but not the other three virus types.
- The mosquito picks up the virus while biting a person with dengue. Later, when this infected mosquito bites other individuals, the dengue virus enters their bloodstream, resulting in infection.
Dengue Fever Symptoms
The onset of symptoms is usually observed after 4-10 days of infection. However, 80% of dengue cases are asymptomatic or show mild symptoms. Dengue symptoms will depend on the severity of the condition.
Mild Symptoms of Dengue Fever
Dengue fever begins with a sudden fever of around 104°F (40°C) with a few other symptoms that include:
- Headache
- Red eyes
- Nausea and vomiting
- Rashes on the skin
- Pain behind the eyes
- Sore throat
- Aching muscles and joints
Most people recover within 2-7 days after the onset of symptoms. However, sometimes, symptoms worsen and become life-threatening.
Severe Symptoms of Dengue Fever
Although less common, some individuals develop severe dengue, which accounts for about 5% of dengue cases globally. Symptoms include:
- Fatigue
- Severe stomach pain
- Difficulty in breathing
- Rapid fluctuation in body temperatures
- Nose or gum bleeding
- Blood in stool, urine, or vomiting
- Restlessness or irritability
Dengue fever becomes severe when the blood clotting cells (platelets) drop in the bloodstream. This can lead to internal bleeding, plasma leakage, or organ failure. Without proper medical attention, severe dengue has a higher risk of death.
Dengue Fever Diagnosis and Tests
The symptoms of dengue are much similar to other infections, such as influenza and malaria. So, for a proper diagnosis of dengue fever, the doctor's evaluation includes the following:
- Examining the symptoms
- Checking travel and medical history
- Performing blood test
Doctors perform the following tests to confirm whether the person is suffering from dengue fever:
- Complete blood count (CBC)
- NS I Antigen
- Reverse transcriptase - Polymerase chain reaction (RT-PCR) test
- Antibody test IgG & IgM
- Liver function test
Dengue Fever Treatment
There is no specific treatment for dengue fever. Rather, managing the symptoms is the only solution. For patients with mild symptoms, treatment includes:
- Liberal oral fluids to stay well hydrated
- Resting
- Using antipyretic paracetamol to bring down fever & reduce body pains
Using non-steroidal, anti-inflammatory drugs such as ibuprofen and aspirin can increase the risk of internal bleeding, so it is best to avoid these drugs.
In some severe cases, hospitalization is necessary, where patients are treated depending upon the severity of symptoms:
- IV fluid administration
- Platelet transfusion in cases with severe thrombocytopenia (less than 10000/cmm)
- Blood transfusion
Some clinical case reports have been reported to show that papaya leaf extract is an effective treatment for dengue fever, but there are no designed randomised controlled studies to prove it. Timely treatment of severe dengue cases can reduce the risk of death to 1%.
Dengue Fever Risks Factors
The risk of contracting dengue fever is high due to a few reasons that include:
- History of dengue fever: Prior infection may increase your symptoms, if you get infected again.
- Living in or travelling to tropical regions: Travelling to or living around tropical and sub-tropical areas increases the risk of contracting dengue fever. This is more common in areas of northeast Asia, the Pacific islands, Australia, Latin America, and Africa.
Dengue Fever Complications
In persons suffering from dengue fever, blood pressure drops drastically, leading to shock. Sometimes, severe dengue can cause plasma leakage, internal bleeding, organ failure, and even death.
Pregnant women suffering from dengue fever can transmit the infection to the newborn during childbirth. Moreover, babies born to pregnant women with dengue fever have higher chances of low birth weight or pre-term birth.
Dengue Fever Prevention
The main approach to prevent or control the transmission of dengue fever is to tackle the mosquito vectors in the following ways:
- Wearing clothes covering whole body
- Using mosquito repellents
- Using mosquito nets
- Avoiding going out in the early morning and evening
- Removing stagnant water surrounding the home
- Trying to avoid camping near still water
- Checking if drains and plant pots are not collecting water
Mosquitoes that bite the infected person can spread the infection to other people around them. So, be vigilant and take preventive measures to avoid transmission.
Vaccination for Dengue Fever
In USA, dengue vaccine known as Dengvaxia is approved by the Food and Drug Administration (FDA) for individuals aged between 9 and 16 with a history of previous dengue infection. However, for people with no history of dengue, administering the vaccine appears to increase the symptoms of dengue fever, which may lead to hospitalization. Therefore no vaccine is as yet available to prevent individuals from contracting dengue.