SAROBON CHAUDAKSHETRIN, M.D., MSc.
Specialist in infectious disease Clinical Microbiologist
Dengue fever has an increased or decreased incidence compared to the past (after Thailand's 20 years of efforts to combat mosquitoes). In the year of a major outbreak, dengue fever has reached its highest level in 5 years, with over 54,000 cases reported. The number of cases has increased by 7,000 per week, with 44 deaths, which is three times higher than last year (2022).
Dengue hemorrhagic fever (DHF) has three levels: the mildest level resembles the flu, called 'Dengue Fever,' with clear skin rashes and bleeding spots. Dengue shock occurs when excessive bleeding leads to shock.
The patient will have a high fever almost all the time. Some children may have seizures due to high fever, loss of appetite, nausea, vomiting, abdominal pain, flushed face, and possible rashes or bleeding spots on the body, arms, and legs. This stage lasts around 2-7 days.
During this phase, the fever begins to drop. The patient may become lethargic, sweat, and have cold hands and feet, with a weak but fast pulse. They may experience abdominal pain, especially under the right rib cage, reduced urine output, and easy bleeding, such as nosebleeds, vomiting blood, or black stools. In severe cases, low blood pressure, shock, and even death may occur. This stage lasts 24-48 hours.
Symptoms begin to improve, and the patient may feel hungry again. Blood pressure rises, the pulse becomes stronger and slower, and urine output increases. Some patients may experience a rash and small bleeding spots on the body.
The dengue virus has 4 strains. A person who has been infected with one strain will develop immunity to that specific strain, but if infected with a different strain, they can get dengue fever again. Generally, the symptoms of the second infection are more severe.
After a second infection, the patient will develop a high level of immunity and may be protected against other strains. The chances of getting infected for a third or fourth time are much lower. Immunity may last for a long time or even for life.
Dengue fever symptoms include:
In contrast, the flu typically involves a high fever lasting for several days, chills, cough, nasal congestion, fatigue, muscle aches, and loss of appetite.
Seek medical attention immediately if you experience abdominal pain, reduced urine output, restlessness or lethargy, cold hands and feet as the fever decreases, dizziness, or fainting. These symptoms can indicate a severe form of the disease. However, even less severe cases should consult a doctor since the condition can worsen without proper treatment.
Qdenga Vaccine is effective in protecting against all four strains of the dengue virus, with an effectiveness rate of 80.2%. It can be given to those who have or have not had dengue fever before, without the need for prior immunity testing, as it is a live-attenuated vaccine. However, this vaccine is not suitable for certain groups.
Dengue fever can be contracted multiple times because the dengue virus has 4 strains. If you are infected with one strain, your body will only develop immunity to that strain and temporary immunity to others. A second infection may increase the risk of severe disease. The vaccine helps reduce the chance of infection and also lessens the severity of the disease.
Dengue fever can affect individuals of all ages and genders. However, certain groups with fragile health should take extra precautions, such as:
Dengue fever can affect anyone, regardless of age, and both children and adults are at risk of severe dengue. Anyone living in a country where dengue is endemic, like Thailand, should consider getting vaccinated to protect themselves from the disease.
Specialist in infectious disease Clinical Microbiologist
