Dengue Fever and Patients with Chronic Diseases

• Diabetes patients infected with dengue fever have a risk of developing severe dengue four times higher than the general population due to weakened immunity. Diabetes may cause an imbalance of inflammation and injury to vascular endothelial cells, increasing vascular leakage, which can lead to dengue shock syndrome.
• In patients with cardiovascular disease, dengue causes plasma leakage and lowered blood pressure, forcing the heart to work harder, increasing the risk of acute heart failure and potentially leading to shock.
• Dengue vaccineAdministered in two doses, three months apart, with no booster required.Reduces infection risk by 80.2%Reduces the chance of severe disease by 85.9% and hospitalization by up to 90.4%

Dengue fever It is not just a common endemic disease everyone has heard about. For people with chronic illnesses such as diabetes, hypertension, heart disease, kidney disease, or obesity, dengue fever can cause severe illness or even death.

Department of Disease ControlThe Ministry of Public Health stated that the highest mortality rate is among those aged 45 and older, especially those with chronic diseases that increase the risk of severe illness, such as diabetes, hypertension, heart disease, kidney disease, chronic lung disease, and obesity.

Why dengue fever is dangerous for people with chronic diseases

Dengue fever is a viral infection caused by the dengue virus, transmitted by Aedes mosquitoes. The virus has four serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. Infection can occur at any age, with symptoms ranging from mild to life-threatening.

In the early stage, patients usually have sudden high fever, headache, muscle and joint pain, or flu-like symptoms. Some patients may develop severe symptoms such as bleeding under the skin or internal organs, low platelet count, dengue shock syndrome, or organ failure, requiring hospital care.

• Dengue fever has no specific treatment. Current care focuses on symptom relief, intravenous fluid administration, circulation management, and monitoring for complications.
• Many patients require hospitalization for 3–7 days, and some may develop complications such as plasma leakage shock, internal organ bleeding, acute kidney failure, or acute heart failure. Patients with chronic diseases often experience these complications more frequently and severely than the general population.

Chronic diseases that increase dengue severity

1. Diabetes mellitus

Diabetes patients infected with dengue fever have a risk of severe dengue four times higher than the general population due to weakened immunity. Diabetes can cause imbalanced inflammation and damage to vascular endothelial cells, increasing vascular leakage and leading to dengue shock syndrome.

Furthermore, poorly controlled diabetes (HbA1C > 7) combined with other comorbidities such as hypertension, chronic kidney disease, stroke, or ischemic heart disease can increase the risk of severe dengue up to 32 times compared to healthy individuals.

2. Cardiovascular diseases

• Dengue causes plasma leakage and lowers blood pressure, forcing the heart to work harder, increasing the risk of acute heart failure and possibly leading to shock.
• Use of thrombolytic or antiplatelet drugs may increase the risk of exacerbating the chronic condition or make it harder to control.
• Moreover, dengue-infected patients have a higher chance of heart failure, acute myocardial infarction, and stroke than the general population. Research confirms that dengue infection is associated with increased risk of severe acute cardiovascular events following infection.

3. Kidney disease

Patients with kidney disease have a fourfold higher risk of severe dengue than the general population. Dengue causes plasma leakage and electrolyte imbalance, placing kidney patients at high risk for acute kidney failure.

4. Obesity

Obese individuals have a 1.5 times higher risk of severe dengue due to chronic inflammation and vascular abnormalities, leading to plasma leakage, bleeding, and organ failure more frequently.

5. Chronic lung disease

Conditions like COPD or asthma are also high-risk groups, with a higher likelihood of severe dengue. The body struggles with oxygen deficiency; plasma leakage and pulmonary edema from dengue can cause severe respiratory distress, increasing hospitalization and mortality rates compared to those without chronic illness.

Patients with chronic diseases who contract dengue fever usually face more severe and complex complications. These include:

• Bleeding Bleeding can occur on the skin, gums, nose, or inside organs such as the gastrointestinal tract, lungs, or brain.
• Shock Shock is a complication that can occur in severe dengue patients, caused by plasma leakage outside blood vessels, leading to reduced circulating blood volume, low blood pressure, and insufficient blood supply to vital organs. Without prompt treatment, this can cause organ failure of the heart, kidneys, or brain, which is life-threatening.
• Acute kidney failure Acute kidney failure is a complication in severe dengue patients, especially those with pre-existing chronic kidney disease. Changes in blood circulation or electrolyte and fluid imbalances can abruptly reduce kidney function, impairing waste removal and water balance, triggering kidney failure.
• Acute heart failure Or myocarditis occurs due to insufficient blood and oxygen supply to the heart muscle, causing reduced heart function or inflammation of heart tissue. This may lead to low blood pressure, shortness of breath, and inadequate blood flow to organs.
• Multi-organ failure Especially in patients with multiple comorbidities combined with shock from circulatory collapse or significant blood loss.

Why dengue vaccination is essential for people with chronic diseases

• Mosquito bite prevention cannot be 100% effective.
• WHO recommends vaccination for patients with comorbidities who are at risk of severe dengue.
• It reduces the chance of infection and symptomatic dengue illness.
• It lowers hospitalization rates and the occurrence of severe dengue.
• It reduces economic and social burdens, including treatment costs and lost workdays or hospital stays.

The dengue vaccine is given in two doses, three months apart, with no booster needed.

• It reduces infection risk by 80.2%.
• It decreases the chance of severe disease by 85.9%.
• It lowers hospitalization rates by up to 90.4%.

Preventive measures to follow alongside vaccination

• Prevent mosquito bites Such as wearing protective clothing, using mosquito repellents indoors, and applying insect repellent creams.
• Eliminate mosquito breeding sites Inspect homes and communities, avoid standing water in containers, and regularly change or cover water storage containers.
• Monitor symptoms from the outset If symptoms like high fever, headache, body aches, abdominal pain, or vomiting appear, seek medical attention immediately without waiting for symptoms to worsen.
• Maintain chronic disease control within normal limits Control diabetes to keep HbA1c within target, manage blood pressure, kidney disease, and heart conditions properly, as this reduces the risk of complications if infected with dengue.

Information courtesy of Dr. Somrat Limmahakhun, infectious disease specialist,Samitivej Sukhumvit Hospital