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Dengue fever is an infectious tropical disease caused by the dengue virus transmitted by Aedes mosquitoes. It can progress to more a deadly form of the disease known as dengue haemorrhagic fever and cause death, and they infect 50 million people a year.
An estimated 500,000 people with severe dengue require hospitalization each year, and with an estimated 2.5% case fatality, annually (source: WHO).
Thailand’s rainy season, running from May through September, is also the high risk period for dengue fever, a potentially serious condition most prevalent in tropical countries, but particularly in Northeastern of Thailand.
Thailand has reported large numbers of Dengue cases nationally. Cases have been reported in Bangkok, Nakhonratchasima, Ubonratchathani, Nakhonsrithammarat, Chonburi, Srisaket, Songkhla, Burirum and Nakhonpathom.
Division of Vector-Borne Diseases, Ministry of Public Health, Dengue Fever Situation in Thailand from 1 January - 15 August 2025, there were 36,439 dengue fever patients and 33 deaths (see updated dengue fever situation report here).
Sudden onset of continuous high fever
Red rashes on skin
Acute pain at the bones, muscles, joints, eye-balls and head
Loss of appetite
Vomiting and nausea
Bleeding from nose, gums and skin
Vaccine tests are still carried out and there is no specific treatment for dengue, but appropriate medical care frequently saves the lives of patients with the more serious dengue haemorrhagic fever. See a doctor immediately for diagnosis and treatment if you experience symptoms of dengue fever.
High Fever: Persistent high fever (38-40°C or 100.4-104°F) lasting 2-7 days, often without a runny nose or cough, distinguishing it from common colds.
It is important for caregivers and health professionals to recognize these symptoms and seek medical attention promptly if dengue fever is suspected, as early diagnosis and appropriate treatment can significantly improve outcomes.
The severity of dengue fever in children refers to the range of symptoms and complications that can occur as a result of the infection. Children are at a higher risk of severe dengue compared to adults because their immune systems are not yet fully developed, and young children may not be able to clearly communicate their symptoms, making it harder for parents to detect the disease early.
The World Health Organization (WHO) classifies dengue fever severity into three levels:
Risk factors for severe dengue include:
Possible complications in children can include bleeding (e.g., gastrointestinal bleeding, bleeding in the brain), shock due to plasma leakage, liver failure, brain inflammation, and kidney failure.
Prevention is crucial, including measures such as eliminating mosquito breeding sites, using mosquito repellents, sleeping under mosquito nets, and considering dengue vaccination when eligible.
Parents should be vigilant for warning signs in young children, such as excessive crying, high-pitched crying, extreme lethargy, not playing, difficulty drinking milk, or frequent vomiting after feeding. If a child shows these symptoms, it’s important to seek medical attention immediately to prevent the disease from worsening, which could be life-threatening.
The goal of managing dengue fever symptoms in children is to provide supportive care, reduce the severity of symptoms, and prevent complications. This can be done both at home and in the hospital, depending on the severity of the condition.
If the child’s symptoms worsen or if any alarming signs such as increased irritability, persistent vomiting, or bleeding are observed, it is crucial to consult a healthcare professional promptly to prevent complications and ensure appropriate treatment.
Pregnancy is a crucial time for expecting mothers to take extra care of their health. However, during the rainy season, a silent threat like dengue fever can lurk, transmitted by mosquitoes such as the Aedes mosquito, posing risks to both mother and baby. Dengue fever in pregnant women is more dangerous than in the general population, as it can lead to severe complications like premature birth or low birth weight for the baby.
The impact on the fetus is one of the significant risks for pregnant women with dengue fever. If a mother contracts dengue fever, the dengue virus can cross the placenta to the fetus. This can result in various complications such as:
The most severe outcomes could be fetal death if dengue fever is severe enough, and conditions like low platelet count and abnormal bleeding could occur, increasing risks such as brain hemorrhage.
The risk of fetal complications is higher if a mother contracts dengue fever in the third trimester of pregnancy (28 weeks onwards), as this is a critical period for fetal growth and nearing the time of birth.
Managing dengue fever in pregnant women requires special precautions to ensure the safety of both the mother and the baby. The treatment is similar to the general population but with added considerations.
It's crucial for expecting mothers to remain vigilant and take preventive measures to reduce the risk of contracting dengue fever and to seek medical advice promptly if symptoms appear.
While Aedes mosquitoes can bite anyone regardless of age or gender, not everyone is equally affected by dengue fever. Some individuals may experience mild symptoms, while others may suffer severe complications that could be life-threatening.
Elderly individuals are a high-risk group for dengue fever, as they are more likely to experience severe symptoms and complications. Aging reduces the immune system's efficiency, making it harder for the body to combat infections, including dengue fever. Additionally, older adults often have pre-existing health conditions like diabetes, hypertension, and heart disease, which can further weaken their immune system and increase the risk of severe complications such as bleeding, organ failure, and even death.
People with pre-existing medical conditions are at higher risk for severe dengue fever complications. Some of these conditions include:
Several other groups are also at an elevated risk for severe dengue fever:
Having a high fever, headache, and body aches doesn't necessarily mean someone has dengue fever. These symptoms can be indicative of other illnesses as well. Therefore, accurate diagnosis is crucial to ensure appropriate treatment and to prevent complications that could be dangerous.
Accurate diagnosis of dengue fever is essential to ensure that patients receive proper, timely treatment and to prevent complications that could be life-threatening. Physicians use several methods to diagnose dengue fever:
An accurate and timely diagnosis of dengue fever is critical because:
Dengue fever is a close-to-home threat carried by the Aedes aegypti mosquito. Although there is no 100% vaccine to prevent it, we can reduce the risk of infection and protect ourselves through simple, proactive measures.
Mosquitoes, particularly Aedes mosquitoes, are carriers of harmful diseases like dengue fever, Zika, and chikungunya—health threats that are especially concerning during rainy seasons when mosquito populations increase. The 3 Clean-Up Policy is an effective strategy to prevent these diseases:
While eliminating mosquitoes is crucial in dengue fever prevention, there is now a dengue fever vaccine available to enhance immunity. This vaccine works by incorporating all four dengue virus strains in a weakened form, which stimulates the body to produce antibodies. These antibodies help prevent the disease or lessen its severity, thereby reducing the risk of complications like bleeding or shock that can be life-threatening and shortening hospital stays.
The vaccine is recommended for individuals aged 9-45 years who:
Before deciding to get vaccinated, it’s advisable to consult a doctor to assess the risks and benefits.
Note: Although the dengue fever vaccine is an important tool, it’s not the only solution. It’s essential to maintain health, control mosquito breeding grounds, and use preventive measures against mosquito bites alongside vaccination.