The measurement of IgM antibodies against the dengue fever virus is used as an aid in the diagnosis of the disease.
Dengue fever is a mosquito-borne viral infection caused by the dengue virus, primarily transmitted to humans through the bite of infected Aedes mosquitoes, particularly Aedes aegypti. It is a significant global health concern, especially in tropical and subtropical regions.
Dengue fever is caused by the dengue virus, a member of the Flaviviridae family. The virus has four distinct serotypes (DEN-1, DEN-2, DEN-3, and DEN-4). Infection with one serotype provides lifelong immunity to that serotype but only temporary immunity to the others. Subsequent infections with different serotypes increase the risk of severe dengue.
Infected Aedes mosquitoes transmit the virus when they bite humans. Once a mosquito is infected, it remains a carrier for life, capable of transmitting the virus to multiple individuals.
Dengue fever can manifest with a range of symptoms, which can vary from mild to severe. Symptoms usually appear 4 to 10 days after being bitten by an infected mosquito. Common symptoms include:
- High Fever: Sudden onset of high fever, often reaching 40°C.
- Severe Headache: Intense pain, particularly behind the eyes.
- Painful Joints and Muscles.
- Rash: A rash that may appear a few days after the fever starts.
- Fatigue and Weakness.
- Nausea and Vomiting: Nausea and vomiting, sometimes accompanied by abdominal pain.
In severe cases, dengue fever can progress to dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), characterized by more severe symptoms, bleeding, and potentially life-threatening complications.
Diagnosing dengue fever involves clinical assessment and laboratory tests. Blood tests, including measurement of IgM and IgG dengue-specific antibodies, are used to confirm the diagnosis.
The presence of IgM-class antibodies to the dengue virus is consistent with acute-phase infection. IgM antibodies become detectable 3 to 7 days following infection and may remain detectable for up to 6 months or longer following disease resolution.
The absence of IgM-class antibodies to the dengue virus is consistent with a lack of infection. However, specimens collected too soon following exposure may be negative for IgM antibodies to the dengue virus. If dengue virus remains suspected, a second specimen collected approximately 10 to 12 days following exposure should be tested.
