Everything You Need to Know About Dengue Tests Before Getting Tested

Overview of Dengue:

Dengue fever is a major public health concern that affects millions of people worldwide in tropical and subtropical areas. It tends to increase in the rainy season and peaks around October-November in India. Dengue is a mosquito-borne viral disease caused by Aedes aegypti with any of four DENV serotypes (DENV-1 to DENV-4) in humans. It can cause no symptoms, from mild symptoms like fever and cold to serious health conditions such as bleeding inside the body and organ failure. Pregnant women and young children have a greater risk of developing severe dengue. Hence the detection of the virus early is critical for better patient management and recovery.

Things to consider before Dengue Testing:

In clinical care efficient and correct diagnosis of dengue amid other infections is of primary importance. Dengue viruses cause a broad range of symptoms, many of which are not specific. Symptoms usually tend to show after 2-4 days of infected mosquito bites with high fever accompanied by bone or muscle pain and if you are in an area where the virus is common then testing is essential. Some of the symptoms to consider before dengue testing:

• Rashes, such as small red patches or spots that may be accompanied by itching

• Unusual bleeding from the nose or gums and easy bruising are other signs of dengue fever.

• Unexplained and intense abdominal pain & vomiting 

• Eye pain, typically behind the eyes, and Severe headache

• Nausea and vomiting with Loose Motions

• Decreased appetite 

• Weaknesses

• Swollen glands

In most cases, symptoms lose intensity within the end of the week. If symptoms persist with fatigue and weakness that could suggest the starting phase of the critical phase which can result in a rapid decrease of platelet count and bleeding internally. The symptoms of dengue are like COVID-19 and other flu infections. It’s always best not to ignore any symptoms as in a few cases people may not develop any symptoms even after getting the virus. Hence, it’s advisable to carefully analyze your symptoms or contact a doctor immediately.

Types of dengue testing:

 The testing of Dengue depends on when symptoms appear and the time of infection. Broadly dengue tests are classified into the following categories:

• Antibody Testing:

These tests majorly help in diagnosing current or recent infections. Primarily they detect two classes of antibodies (IgG and IgM) which are produced by the body in case of dengue infection. As the body immune system produces mixed levels of antibodies over the course of infection, combining multiple tests will aid in better diagnosis

• Dengue NS1 test (NS1 antigen test) 
• IgM ELISA test for dengue 
• IgG ELISA test for dengue 
• IgM/IgG ratio
• IgA ELISA test for dengue
• Hemagglutination-inhibition test

• Molecular Testing: 

Molecular tests detect the genetic material (DNA) of the 4 serotypes dengue virus causing the infection in the blood during the acute phase of dengue infection after symptoms appear. A major advantage of PCR-based techniques is that viral RNA can be detected from the onset of illness and is specific, sensitive, fast, less complicated, and cheaper than virus isolation methods.

• RT-PCR (Real-Time PCR)
• Isothermal Amplification Based Tests (LAMP)
• Complete blood count (For checking platelet and WBC count)

Positive results in the above tests indicate dengue virus infection. But in case of negative results, it can be due to low viral load in the blood or if the test is done more than seven days after your symptoms began. If molecular tests come back negative, doctors can recommend testing antibodies to confirm the presence of dengue virus.

Steps to avoid dengue Fever:

When an infected mosquito bites it causes dengue. The mosquitoes can bite both day and night, so safety is important the whole day. A few ways to protect ourselves from dengue bites are:

• Wear long-sleeved shirts and pants.
• Use mosquito repellents on the skin.
• Keep the surroundings clean and check for stagnation to avoid the breeding of mosquitoes.

Conclusion:

Dengue infects nearly 400 million individuals per year around the globe. Early and accurate laboratory diagnosis of DENV infection is critical for effective patient management. Dengue infection is mild and mostly can be treated at home with rest and extra fluids. Few severe cases may require hospital requirements. Therefore, before you consider a blood test for dengue, you must know about the different types of blood tests available, and testing should be done accordingly.