Dengue dengue old infection

Blood test Dengue IgG (DENGG from serum)

Dengue is a viral disease transmitted by mosquitoes of the genus Aedes, particularly the Aedes aegypti mosquito. The virus can cause symptoms ranging from mild flu-like symptoms to severe and potentially life-threatening conditions.

Why this blood test?

If you get Dengue for the second time, it is dangerous and you cannot travel to Dengue area without vaccination.

Therefore, it is important to test beforehand to see if you have had Dengue before.

These tests can detect the presence of the virus and antibodies in the blood, which helps in making an accurate diagnosis and determining the best treatment options.

In general, IgG antibodies are usually detected in the blood after about 1 to 2 weeks after the onset of symptoms. This means that IgG antibodies develop in the later stages of dengue infection, after the virus has multiplied in the body and the immune system has begun to respond.

The risk of contracting dengue a second time, also known as secondary dengue infection, can be more severe than with the first infection. This phenomenon is known as "antibody-dependent amplification" or "antibody-dependent exacerbation" of dengue (ADE - Antibody-Dependent Enhancement).

Here's how it works:

Initial infection: When a person is first exposed to the dengue virus and recovers, that person develops antibodies against that specific virus serotype (variant). These antibodies provide protection against reinfection by the same serotype.

Second infection: If the same person is later exposed to a different serotype of dengue virus, the antibodies developed in response to the first infection may paradoxically increase the risk of more severe symptoms. This is because the antibodies present do not effectively neutralize the new virus serotype, but rather help bring the virus into cells where it can multiply. This can lead to a more severe form of the disease, such as dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS).

So once you are infected with Dengue, it is advisable to get vaccinated before entering another dengue area.

If you have symptoms, always see your family doctor or tropical doctor.