Some patients with dengue fever progress to dengue hemorrhagic fever (DHF), a severe and sometimes fatal form. Dengue fever is an acute febrile disease caused by one of the serotypes of the dengue virus, a mosquito-borne illness spread by the genus Aedes. It also goes by breakbone fever, hemorrhagic fever, dandy fever, and infectious thrombocytopenic purpura. DHF presents with bleeding diathesis and hypovolemic shock. These viruses are related to those that cause West Nile infection and yellow fever.
Pathophysiology
The initial phase looks like dengue fever and other febrile viral illnesses. The vector deposits the virus in the skin, viremia develops within a few days, and symptoms appear by the 5th day. Shortly after the fever breaks, or sometimes within 24 hours before, plasma leakage and hemorrhagic symptoms begin. Vascular leakage produces hemoconcentration and serous effusions and can drive circulatory collapse. Untreated, DHF most likely progresses to dengue shock syndrome.
Statistics and Incidences
Dengue is a reportable disease in the United States; report known or suspected cases to public health authorities. About half the world's population now lives in areas at risk, across more than 100 countries where dengue is endemic, and the World Health Organization estimates 100 to 400 million infections each year. Reported cases have surged: 2024 brought a record of more than 14 million reported cases worldwide (WHO). With early detection and proper supportive care the case-fatality rate is under 1%, but untreated severe dengue can be far higher. Dengue occurs at any age but is more common in children.
Causes
DHF is caused by infection with one of the four serotypes of dengue virus, a Flavivirus (a genus of single-stranded, nonsegmented RNA virus). The virus is transmitted by day-biting Aedes mosquitoes that breed in stagnant water; Aedes aegypti has white dots at the base of its wings and white bands on its legs. The incubation period is 3 to 10 days.
Clinical Manifestations
Symptoms usually start 4 to 6 days after infection and can last up to 10 days. Expect sudden high fever and severe headaches. As the virus spreads, it affects the lymph and blood vessels. Bleeding from the nose and gums is characteristic of DHF. The virus can penetrate the liver and cause fatal damage, and the circulatory system ultimately fails if the disease is not treated promptly.
Prevention
There is no vaccine yet, so prevention is about avoiding bites. Stay away from heavily populated residential areas. Use skin-safe mosquito repellents, even indoors. Outdoors, wear long-sleeved shirts and long pants tucked into socks. Keep window and door screens intact or use mosquito nets. Empty or cover bottles, cans, and any containers holding stagnant water, since these are mosquito breeding sites.
Complications
Dengue is not always recognized in the United States, so cases often end up with complications. The main one is dengue shock syndrome; impending shock shows up as abdominal pain, vomiting, and restlessness.
Assessment and Diagnostic Findings
Laboratory criteria for diagnosis include any one of the following. Isolate the dengue virus from serum, plasma, leukocytes, or autopsy samples. Demonstrate a fourfold or greater change in reciprocal immunoglobulin or IgM antibody titers to one or more dengue virus antigens in paired serum samples. Demonstrate dengue virus antigen in autopsy tissue by immunohistochemistry or immunofluorescence. Detect viral genomic sequences in autopsy tissue, serum, or cerebrospinal fluid by PCR. On CBC, DHF often shows an increased hematocrit secondary to plasma extravasation or third-space fluid loss, and a decreased platelet count confirms dengue. Run a guaiac test for occult blood in the stool on all patients suspected of dengue infection.
Medical Management
Management is straightforward when caught early. Oral rehydration therapy is recommended for moderate dehydration from high fever and vomiting, and IV fluids are indicated when dehydration is more significant. Patients with internal or GI bleeding may need transfusion, and those with coagulopathy may need fresh frozen plasma. Increasing oral fluids helps. Warn patients to avoid aspirin and other NSAIDs, since they thin the blood and raise the risk of hemorrhage.
Nursing Management
Nursing Assessment
Evaluate heart rate, temperature, and blood pressure. Check capillary refill, skin color, and pulse pressure. Look for bleeding in the skin and at other sites, assess for increased capillary permeability, and measure urine output.
Nursing Diagnosis
Based on the assessment data, the major nursing diagnoses are: risk for bleeding related to possible impaired liver function; deficient fluid volume related to vascular leakage; pain related to abdominal pain and severe headaches; risk for ineffective tissue perfusion related to failure of the circulatory system; and risk for shock related to circulatory dysfunction.
Nursing Care Planning and Goals
The patient should be free of signs of bleeding, show lab results within normal range, maintain fluid volume at a functional level, report pain relieved or controlled, follow the prescribed pharmacologic regimen, demonstrate adequate tissue perfusion, display hemodynamic stability, and be afebrile and free of other signs of infection.
Nursing Interventions
Measure blood pressure as indicated. Note where the patient reports pain and whether it is increasing, diffuse, or localized. Maintain patency of vascular access for fluid administration or blood replacement. Periodically review the medication regimen to flag anything that might worsen bleeding. Establish 24-hour fluid replacement needs. For nosebleeds, elevate the patient and apply an ice bag to the bridge of the nose and the forehead. Place the patient in Trendelenburg position to restore blood volume to the head.
Evaluation
Confirm the goals were met: no signs of bleeding, lab results within normal range, fluid volume maintained at a functional level, pain relieved or controlled, prescribed regimen followed, adequate tissue perfusion, hemodynamic stability, and the patient afebrile and free of other signs of infection.
Discharge and Home Care Guidelines
Tell the patient to avoid caffeine and alcohol to reduce the effects of diuresis. Have them comply with recommended medical and laboratory followups. Recommend a soft toothbrush to reduce injury to the oral mucosa. Recommend foods rich in vitamin K to promote blood clotting. Educate the patient on the use of mosquito nets and insecticides.
Documentation Guidelines
Document factors that potentiate blood loss; baseline vital signs, mentation, urine output, and subsequent assessments; results of laboratory and diagnostic studies; the degree of deficit and current sources of fluid intake; I&O and fluid balance; the patient's description of and acceptable level of pain; the plan of care; the teaching plan; the response to interventions, teaching, and actions performed; attainment or progress toward desired outcomes; and any modifications to the plan of care.
Frequently Asked Questions
What is the difference between dengue fever and dengue hemorrhagic fever? Dengue fever is the acute febrile illness most infected people get. Dengue hemorrhagic fever (DHF) is the severe form, where plasma leaks out of the vessels, platelets fall, and the patient bleeds. DHF can progress to dengue shock syndrome and circulatory collapse if it is not caught and treated.
What causes dengue and how does it spread? Dengue is caused by one of four serotypes of the dengue virus, a Flavivirus. It spreads through the bite of day-biting Aedes mosquitoes (mainly Aedes aegypti) that breed in stagnant water. It does not pass directly from person to person (WHO).
Why are aspirin and NSAIDs avoided in dengue? Aspirin and other NSAIDs interfere with platelets and clotting, which raises the bleeding risk in a disease that already drops the platelet count. Acetaminophen is preferred for fever and pain control.
What are the warning signs that dengue is turning severe? Severe abdominal pain, persistent vomiting, restlessness, bleeding from the gums or nose, and a falling platelet count with a rising hematocrit signal impending shock. These patients need urgent fluid management and monitoring (CDC).
Is there a treatment or vaccine for dengue? There is no specific antiviral cure. Care is supportive: fluid replacement, monitoring of hematocrit and platelets, and transfusion for significant bleeding. Dengue vaccines exist for specific groups in endemic areas, so prevention still centers on avoiding mosquito bites (WHO).
How is the diagnosis confirmed? Diagnosis combines clinical signs with labs: a rising hematocrit from plasma leakage, a falling platelet count, and confirmatory testing such as viral isolation, dengue antigen detection, PCR, or paired IgM/IgG antibody titers.