What is Dengue fever (DH)?
Dengue fever is a painful, weakening viral infection transmitted by a bite of an infected female Aedes aegypti mosquito, the main mosquito that spreads dengue fever during the monsoons.
Person-to-person transmission does not occur. Mosquitoes turn out to be infected with dengue fever by biting an infected person. The dengue fever is then transmitted to someone else when an infected mosquito bites that person. The virus is active in the blood of the infected person from day one to seven of the fever phase. Therefore, anyone who might be in contact with infected patient’s blood such as a doctor or other heath care worker can be exposed.
Dengue fever may spread from an infected pregnant mother to her fetus. So, extra care should be taken by pregnant women in areas where the virus may be present.
Some patients suffering from dengue may develop bleeding. The frequent sites for bleeding are:
From time to time, patients may have coffee ground vomiting or black stools. This indicates bleeding in the gastrointestinal tracts and is considered serious.
Dengue fever is a flu-like illness that affects infants, young children, and adults; it may not cause any noticeable symptoms especially in mild cases.
The Center for Disease Control and Prevention estimates that at least 400 million cases of dengue fever occur across the globe every year. Tropical regions are heavily affected.
This is a disease of poverty in urban and semi-urban regions. If you live in or travel to a tropical or subtropical region often, you are at a higher risk of contracting dengue fever. You are also at greater risk of contracting dengue fever if you have been infected before. In addition to that, the symptoms might be more severe.
Areas that have the greatest risk of infection comprise:
- Sub-Saharan Africa
- Central America
- Indian Subcontinent
- The Caribbean
- Pacific Islands
- South America (except Argentina, Chile, and Paraguay
- Southeast Asia (especially Thailand, Singapore)
- Southern China
- Northern parts of Australia
Here in the Philippines, especially when it’s the rainy season, dengue is just around the corner.
Symptoms of Dengue fever
There are four distinct serotypes of the dengue virus: DEN1, DEN2, DEN3 and DEN4
Sometimes, the symptoms are mild and are mistaken of the flu and other viral infection. If you contract dengue fever, symptoms usually begin about four to seven days after the initial infection. Younger children and people who have never experienced infection before may have a milder illness than older children and adults.
However, serious problems can develop. These include:
Dengue haemorrhagic fever (DHF)
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.
Dengue shock syndrome (DSS)
Not so often, there are patients suffering from dengue that may progress to massive bleeding, shock, and d***h.
Signs and symptoms normally last for about 10 days and can include several sicknesses:
- Sudden, high fever (up to 106 degrees Fahrenheit or 41 degrees Celsius)
- Severe headache
- Severe muscle, bone and joint pain
- Pain behind your eyes
- Widespread skin rash (appearing between two and five days after the initial fever)
- Mild to severe nausea
- Mild to severe vomiting
Watch for signs if temperature drops 3 to 7 days after the symptoms began. While there are some people who recover within a week or so, there are also instances wherein symptoms aggravate and turn out to be life-threatening. In this case, the number of clot-forming cells or the platelets in your bloodstream goes down; in which may cause:
- Rarely, mild bleeding from the nose or gums
- Severe abdominal pain
- Persistent vomiting
- Black, tarry stools
- Swollen lymph glands
- Mild bruising on the skin
- Drowsiness or irritability
- Febrile convulsions
- Difficulty of breathing
- Problems with lungs, liver, and heart.
People with weakened immune systems – as well as those with a second or subsequent dengue infection – are believed to be at greater risk for developing dengue hemorrhagic fever.
Diagnosing Dengue Fever
Dengue fever testing is used to determine whether a person with signs and symptoms has been infected with the virus. The infection is difficult to diagnose without laboratory tests because symptoms may initially resemble to those other diseases.
Molecular testing (polymerase chain reaction or PCR)
This type of test detects the genetic material of the dengue virus in the blood within the first week after symptoms like fever appear and can be used to determine which of the 4 serotypes is causing the infection. Only certain public health laboratories are able to provide the test after verifying that they can successfully perform the test. Results can take from four days to two weeks.
Molecular tests of blood are not likely to detect the virus after 7 days of illness. If the result of a PCR test is negative, an antibody test can be used to help establish a diagnosis.
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.
Doctors use blood tests to check for viral antibodies or the presence of infection. Moreover, diagnosis of acute or on-going, or recent dengue infection can be established by testing serum samples during the first 5 days of symptoms and / or early convalescent phase which is more than five days of symptoms.
Treating Dengue Fever
There is no specific medication or treatment specifically for dengue infection. You should use over-the-counter pain relievers with acetaminophen to reduce your fever, headache, and joint pain and although antibiotics do not help, you can try and attack it with water. However, you need to avoid medicines with aspirin and ibuprofen. Why? Because it can worsen the bleeding.
Your doctor should perform a medical exam, and they should be very careful in prescribing medicines. Medicine that decrease the platelets should be avoided. Infected patients should also rest and eat nutritious diet.
Dengue fever can cause diarrhea and vomiting which can cause dehydration. It is therefore important for dengue patients to drink plenty of fluids; take Oral Rehydration Salt / ORS.
Adequate fluid intake is very essential and becomes more important in case DF progresses into DHF or DSS where loss of body fluid / blood is the most important element.
If you feel worse after the first 24 hours of illness or after your fever goes down, you should go to the hospital as soon as possible to check for complications.
How to Prevent Dengue Fever
There is no vaccine available to prevent dengue fever and there are no specific medications to treat dengue infection. The best method of protection and prevention is to avoid mosquito bites and to reduce the mosquito population.
Things to do when living or travelling in an endemic area:
- Avoid heavily populated residential areas
- Turn over empty pails or buckets so they won’t collect excess water or if not cover it well
- Clean out empty flower pots and do not over water potted plants
- Use mosquito repellent on all exposed areas indoors and outdoors, during the day as well as at night
- Wear long-sleeved shirts and pants tucked into socks; in addition,
- Use air conditioning instead of opening windows
- Use mosquito nets if sleeping areas are not screened
- Always cover the trashcan or dustbin when not in use.
- One natural method is to plant tulsi, plant that do not allow mosquitoes to breed, near the window.
- Light camphor as repellant in a room and close all the doors and windows.
Reducing the mosquito population involves getting rid of mosquito breeding areas. These areas include any places where mosquitoes lay her eggs such as:
- Artificial containers that hold water in and around the home
- Pet dishes
- Empty flower planters
- Flower vases inside the house
- Watering containers
- Water storage barrels
- Any empty vessel
Always check, empty, and clean these areas to avoid accumulation of mosquitoes.
Mosquitoes that spread dengue bite during the day and night; with that said, you should sleep under a mosquito bed net, and wear repellent.
Now that it is the rainy season, mosquitoes are abundant. They like to stay in places where water is stagnant. Avoid these places and be sure to watch yourself!