Dengue

 

Dengue is a viral infection transmitted to humans through the bites of infected female mosquitoes, primarily the Aedes aegypti species and, to a lesser extent, Aedes albopictus. This mosquito-borne tropical disease has become one of the fastest-growing public health concerns worldwide, affecting millions of people annually across more than 100 countries.

• The dengue virus belongs to the Flavivirus genus and exists in four distinct serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. Infection with one serotype provides lifelong immunity to that specific type but only temporary and partial protection against the other three serotypes. Subsequent infections with different serotypes significantly increase the risk of developing severe dengue, previously known as dengue hemorrhagic fever or dengue shock syndrome.
• Dengue has evolved from a sporadic disease to a major global health challenge. The World Health Organization estimates that approximately 400 million dengue infections occur annually, with about 100 million people developing symptomatic illness. The disease burden has increased dramatically over the past several decades due to factors including rapid urbanization, increased international travel, climate change affecting mosquito breeding patterns, and inadequate vector control measures.
• The Aedes aegypti mosquito, the primary dengue vector, has distinctive characteristics that make it particularly effective at transmitting the virus. These mosquitoes are day-biters, with peak biting activity occurring in the early morning and before dusk. They prefer to breed in clean, stagnant water found in artificial containers near human habitations, such as flower vases, water storage containers, discarded tires, buckets, and plant saucers. A single infected mosquito can transmit the virus to multiple people during its lifespan.
• Dengue typically occurs in tropical and subtropical climates worldwide, particularly in urban and semi-urban areas. Major endemic regions include Southeast Asia, the Western Pacific islands, Latin America, the Caribbean, Africa, and parts of the Middle East. However, the geographic distribution continues to expand as mosquito vectors spread to new areas.
• The incubation period for dengue ranges from 4 to 10 days after being bitten by an infected mosquito. Most infected individuals either remain asymptomatic or develop mild symptoms. However, some progress to severe dengue, which can be life-threatening without appropriate medical care. Severe dengue is characterized by plasma leakage, severe bleeding, and organ impairment.
• Risk factors for developing dengue include living in or traveling to endemic areas, previous dengue infection (which increases the risk of severe disease upon reinfection with a different serotype), young age or advanced age, compromised immune status, and chronic conditions such as diabetes or asthma.

2. Symptoms of Dengue

Dengue fever manifests along a spectrum ranging from asymptomatic infection to severe, potentially fatal disease. The clinical presentation varies depending on the patient's age, immune status, infecting serotype, and whether it is a primary or secondary infection.

Asymptomatic and mild dengue:

• Approximately 75% of dengue infections are asymptomatic, meaning infected individuals show no signs of illness but can still transmit the virus to mosquitoes, perpetuating the transmission cycle.
• Mild symptomatic dengue may present with nonspecific flu-like symptoms that resolve within a week without complications. These cases are often undiagnosed as patients may not seek medical attention.

Classic dengue fever:

• The hallmark presentation of dengue fever typically begins abruptly with high fever, often reaching 104-106°F (40-41°C). This fever usually lasts 2-7 days and may follow a biphasic pattern, where fever drops briefly then returns.
• Severe headache is one of the most prominent symptoms, often described as intense frontal headache or pain behind the eyes. The retro-orbital pain worsens with eye movement.
• Muscle and joint pain can be extremely severe, giving dengue fever its colloquial name "breakbone fever." The pain affects the back, muscles, joints, and bones throughout the body, causing significant discomfort and mobility issues.
• Skin manifestations include a characteristic maculopapular rash that typically appears 2-5 days after fever onset. The rash may begin on the trunk and spread to the extremities and face, often sparing the palms and soles. Some patients develop flushing of the face and neck during the initial fever phase.
• Nausea, vomiting, and loss of appetite are common gastrointestinal symptoms that can lead to dehydration if not properly managed. Some patients experience a metallic taste in their mouth.
• Extreme fatigue and weakness persist throughout the illness and may continue for weeks after fever resolution. This post-dengue fatigue can significantly impact daily activities and work productivity.
• Mild bleeding manifestations may occur, including easy bruising, nosebleeds, bleeding gums, or small red spots on the skin (petechiae). These minor bleeding signs do not necessarily indicate progression to severe dengue but warrant close monitoring.
• Enlarged and tender liver (hepatomegaly) may be detected on physical examination, sometimes accompanied by abdominal pain or tenderness in the right upper quadrant.

Warning signs of severe dengue:

• Certain symptoms signal potential progression to severe dengue and require immediate medical attention. These typically appear during the critical phase, which begins as fever subsides, usually 3-7 days after symptom onset.
• Severe abdominal pain or persistent vomiting prevents adequate fluid intake and may indicate plasma leakage or internal bleeding.
• Persistent vomiting with inability to keep down liquids leads to dehydration and electrolyte imbalances.
• Bleeding from nose, gums, or in vomit or stool indicates more significant hemorrhagic complications.
• Vomiting blood or blood in stools (which may appear black and tarry) suggests gastrointestinal bleeding requiring urgent evaluation.
• Difficulty breathing or rapid breathing may indicate fluid accumulation in the chest (pleural effusion) or lungs due to plasma leakage.
• Cold, clammy skin with rapid, weak pulse suggests circulatory compromise and impending shock.
• Extreme fatigue, restlessness, or irritability, particularly in children, may signal deteriorating condition.
• Sudden drop in body temperature below normal accompanied by profuse sweating and circulatory collapse indicates dengue shock syndrome.

Severe dengue (dengue hemorrhagic fever and dengue shock syndrome):

• Severe dengue represents a potentially fatal complication occurring in approximately 5% of dengue cases. It typically develops in the critical phase as fever subsides, usually 3-7 days after initial symptoms.
• Plasma leakage is the defining feature of severe dengue, where fluid leaks from blood vessels into surrounding tissues and body cavities. This causes hemoconcentration (increased concentration of blood cells), pleural effusion, ascites (fluid in the abdomen), and eventually circulatory failure.
• Severe hemorrhagic manifestations include significant bleeding from the gastrointestinal tract, urinary tract, or other sites. Patients may have heavy menstrual bleeding, severe nosebleeds, or bleeding into the skin causing large bruises or purpura.
• Organ impairment affects the liver (causing elevated liver enzymes and jaundice), heart (myocarditis), kidneys (acute kidney injury), and brain (encephalopathy or encephalitis), though the latter is rare.
• Dengue shock syndrome occurs when plasma leakage becomes severe enough to cause circulatory collapse. Signs include narrow pulse pressure (less than 20 mmHg), cold extremities, weak or absent pulse, prolonged capillary refill time, altered consciousness, and ultimately, profound shock. This is a medical emergency requiring intensive care.

Special considerations:

• In children, dengue symptoms may be less specific and milder initially but can progress rapidly to severe disease. Parents and caregivers should watch for warning signs including persistent vomiting, abdominal pain, lethargy, or breathing difficulties.
• Pregnant women with dengue face increased risks including preterm birth, low birth weight, and fetal distress. Vertical transmission from mother to baby can occur, particularly if the mother develops dengue around delivery time.
• Elderly patients and those with chronic conditions like diabetes, hypertension, or heart disease may experience more severe manifestations and complications.

3. Medical and Blood Tests for Identifying Dengue

Accurate and timely diagnosis of dengue is essential for appropriate clinical management, disease surveillance, and prevention of complications. Dengue diagnosis relies on a combination of clinical evaluation, laboratory confirmation, and sometimes imaging studies.

• Clinical diagnosis:

In endemic areas during outbreaks, clinical diagnosis based on characteristic symptoms and physical examination may be sufficient for managing uncomplicated cases. However, laboratory confirmation is important for differentiating dengue from other febrile illnesses with similar presentations such as malaria, chikungunya, Zika virus, leptospirosis, typhoid fever, and influenza.

• Virological tests (detecting the virus or its components):

NS1 antigen test detects a dengue viral protein (non-structural protein 1) that circulates in high concentrations in the blood during the early phase of infection, typically from the first day of fever onset until day 5-7 of illness.

• This rapid diagnostic test provides results within hours and can be performed at point-of-care settings. The test uses blood serum, plasma, or whole blood. A positive NS1 result confirms acute dengue infection.
• Sensitivity of NS1 testing ranges from 50-90% depending on the day of illness, infecting serotype, and whether it is primary or secondary infection. The test is more sensitive during primary infections and in the first few days of illness.
• Normal value: Negative (no NS1 antigen detected). A positive result confirms dengue infection.
• RT-PCR (Reverse Transcription Polymerase Chain Reaction) detects dengue viral RNA in blood and can identify the specific serotype causing infection. This is the gold standard for early dengue diagnosis.
• RT-PCR is highly specific and sensitive but requires specialized laboratory equipment and trained personnel. It is most useful during the first 5 days of illness when viremia (virus in blood) is highest.
• This test is particularly valuable for surveillance purposes, identifying circulating serotypes, and research applications. Results may take several hours to days depending on laboratory capacity.
• Normal value: Negative (no viral RNA detected). Detection of dengue viral RNA confirms active infection and identifies the serotype.
• Virus isolation from blood samples through cell culture is the definitive diagnostic method but is rarely used clinically due to technical complexity, time requirements (7-10 days), specialized facilities needed, and availability of faster diagnostic methods.

Serological tests (detecting antibodies):

• IgM antibody test detects dengue-specific IgM antibodies, which appear in the blood starting around day 4-5 of illness and can persist for 2-3 months after infection.
• A positive IgM result suggests recent or current dengue infection. However, IgM may remain positive for weeks after recovery, so timing is important for interpretation. IgM testing is most reliable from day 5 onwards after symptom onset.
• Rapid IgM tests provide results within 15-20 minutes using blood samples, making them useful for point-of-care diagnosis in resource-limited settings.
• Normal value: Negative (no IgM antibodies detected). Positive IgM indicates recent dengue infection.
• IgG antibody test detects dengue-specific IgG antibodies. In primary dengue infections, IgG appears later (after 7-10 days) and rises slowly. In secondary infections (infection with a different serotype in someone previously infected), IgG rises rapidly and to high levels.
• IgG antibodies persist for life after dengue infection, providing long-term immunity to the specific serotype but not to others.
• The presence of high IgG levels early in illness or a four-fold rise in IgG titers between acute and convalescent samples (taken 2 weeks apart) confirms dengue infection.
• Normal value: Negative (no IgG antibodies detected). Positive IgG indicates past or current dengue infection.
• IgM/IgG ratio helps distinguish primary from secondary dengue infections, which has prognostic value since secondary infections carry higher risk of severe dengue. Primary infections show higher IgM:IgG ratios, while secondary infections show higher IgG:IgM ratios.

Complete blood count (CBC):

• Complete blood count provides important information about disease severity and helps monitor progression, though changes are not specific to dengue.
• White blood cell count (WBC) typically shows leukopenia (low white blood cell count), particularly lymphopenia early in illness, followed by lymphocytosis with atypical lymphocytes appearing later.
• Normal WBC: 4,000-11,000 cells/μL. In dengue, counts often drop below 4,000 cells/μL.
• Platelet count progressively decreases during dengue infection, with thrombocytopenia (low platelet count) being a characteristic feature. The nadir (lowest point) typically occurs during the critical phase around days 4-7 of illness.
• Normal platelet count: 150,000-450,000 cells/μL. In dengue, counts commonly drop below 100,000 cells/μL. Counts below 20,000-50,000 cells/μL indicate severe thrombocytopenia requiring close monitoring and possible platelet transfusion if there is active bleeding.
• Hematocrit (HCT) measurement is crucial for detecting hemoconcentration, which indicates plasma leakage in severe dengue. Serial hematocrit monitoring guides fluid management.
• Normal hematocrit: Male 40-54%, Female 36-46%. A rise of 10-20% above baseline or population normal suggests significant plasma leakage characteristic of severe dengue.

Liver function tests:

• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are liver enzymes that become elevated in dengue due to viral effects on liver cells. Levels typically peak during the critical phase.
• Normal AST: 10-40 U/L, Normal ALT: 7-56 U/L. In dengue, these may rise to several hundred or even thousand U/L in severe cases. Markedly elevated transaminases may indicate severe liver involvement.

Other blood tests:

• Blood coagulation profile including prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen levels may be abnormal in severe dengue with bleeding complications.
• Serum albumin decreases due to plasma leakage in severe dengue.
• Electrolytes and renal function tests (creatinine, blood urea nitrogen) help assess hydration status and detect kidney complications.
• Blood glucose monitoring is important as hypoglycemia can occur, particularly in children with severe dengue.

Imaging studies:

• Chest X-ray or ultrasound may detect pleural effusion or ascites, indicating plasma leakage in severe dengue.
• Abdominal ultrasound helps identify gallbladder wall thickening, ascites, and assess organ size.

Testing strategy based on timing:

• Days 0-5 of illness: NS1 antigen test or RT-PCR are most appropriate for early diagnosis.
• Days 4-5 onwards: IgM/IgG serology becomes useful as antibodies begin to appear.
• Throughout illness: Complete blood count with platelets and hematocrit should be monitored daily or more frequently in hospitalized patients to detect complications.

Important diagnostic considerations:

• No single test is 100% sensitive or specific for dengue. Combining clinical assessment with appropriate laboratory tests improves diagnostic accuracy.
• False negatives can occur with any test depending on timing, test quality, and individual patient factors. If clinical suspicion remains high with negative initial testing, repeat testing or alternative methods should be considered.
• Cross-reactivity may occur with other flavivirus infections (Zika, yellow fever, Japanese encephalitis), particularly in serological tests, though this is less problematic with NS1 and PCR testing.
• Regular monitoring of blood counts is essential even after diagnosis to detect early signs of complications and guide management decisions.

4. How Dengue Can Be Treated

There is no specific antiviral treatment for dengue fever. Management focuses on supportive care, careful monitoring for complications, and appropriate interventions when warning signs or severe dengue develops. The cornerstone of dengue treatment is adequate fluid replacement and close clinical monitoring.

Management of uncomplicated dengue fever (outpatient care):

• Fluid replacement is the single most important intervention in dengue management. Patients should maintain adequate oral hydration throughout the illness, particularly during the fever phase and critical phase (days 3-7 of illness).
• Recommended fluid intake includes water, oral rehydration solutions, coconut water, fruit juices, and soups. Adults should aim for at least 2-3 liters daily, adjusted based on body size, fever intensity, and fluid losses from vomiting or sweating. Children require approximately 50-100 mL/kg body weight over 24 hours in divided amounts.
• Fever management involves using antipyretics to control high fever and associated discomfort. Acetaminophen (paracetamol) is the preferred medication for fever reduction in dengue. Adults may take 500-1000 mg every 4-6 hours as needed, not exceeding 4 grams daily. Children's doses are calculated based on weight (10-15 mg/kg every 4-6 hours).
• Rest is essential during the acute illness phase. Physical activity should be minimized to allow the body to focus energy on fighting infection and recovery.
• Close monitoring for warning signs requires daily assessment, including checking for severe abdominal pain, persistent vomiting, bleeding manifestations, lethargy, restlessness, or breathing difficulties. Patients or caregivers should be educated about these warning signs and instructed to seek immediate medical attention if they develop.
• Daily blood tests monitoring platelet count and hematocrit help track disease progression. Falling platelets and rising hematocrit may indicate transition to the critical phase requiring hospitalization.

Management of dengue with warning signs (hospitalized care):

• Patients exhibiting warning signs require hospital admission for intensive monitoring and intravenous fluid management. This typically occurs during the critical phase when plasma leakage begins.
• Intravenous fluid therapy is carefully calculated and administered to replace plasma losses while avoiding fluid overload. Initial fluid resuscitation uses isotonic crystalloid solutions such as normal saline or Ringer's lactate. The rate and volume are adjusted based on clinical response, hematocrit changes, and vital signs.
• Fluid management follows specific protocols with close monitoring of intake and output, vital signs every 1-2 hours, hematocrit checks every 4-6 hours initially, and clinical assessment of hydration status, perfusion, and respiratory status.
• The goal is to maintain adequate tissue perfusion while avoiding complications of fluid overload such as pulmonary edema or worsening pleural effusion.

Management of severe dengue (intensive care):

• Severe dengue with significant plasma leakage, severe bleeding, or organ impairment requires intensive care unit management with experienced medical teams.
• Aggressive intravenous fluid resuscitation is immediately initiated for patients in shock, following standardized protocols. Initial boluses of 10-20 mL/kg of crystalloid solution are administered over 15-30 minutes and repeated based on response.
• Continuous monitoring includes frequent vital signs, urine output (catheter placement for accurate measurement), serial hematocrit checks, electrolytes, blood gases, and cardiac monitoring.
• Blood component therapy may be necessary for severe bleeding or critical thrombocytopenia with active bleeding. Platelet transfusions are given when platelet counts are critically low (<20,000 cells/μL) with active bleeding or high bleeding risk. Fresh frozen plasma or packed red blood cells may be needed for significant blood loss.
• Oxygen therapy and respiratory support may be required if plasma leakage causes pleural effusion or pulmonary edema affecting breathing.
• Management of organ complications including liver failure, kidney injury, or cardiac involvement requires specialized interventions and supportive measures.

Monitoring parameters during treatment:

• Vital signs including blood pressure, pulse rate, respiratory rate, and temperature are monitored regularly, with frequency depending on disease severity (every 1-4 hours in hospitalized patients).
• Hematocrit monitoring guides fluid management. Falling hematocrit after adequate fluid resuscitation may indicate bleeding, while persistently elevated hematocrit suggests inadequate fluid replacement.
• Platelet counts are checked daily or more frequently to assess bleeding risk and disease progression.
• Urine output monitoring ensures adequate kidney perfusion and function. Decreased urine output may indicate inadequate fluid resuscitation or kidney complications.
• Clinical assessment includes evaluation of capillary refill time, skin perfusion, level of consciousness, presence of bleeding, and respiratory status.

Recovery phase management:

• As patients enter the recovery phase (usually after day 7-8), plasma leakage stops and reabsorbed extravascular fluid returns to circulation. This may cause fluid overload in some patients, requiring diuretics.
• Gradual reduction of intravenous fluids and transition to oral intake occurs as the patient improves.
• Convalescence period requires adequate rest, nutritious diet, and gradual return to normal activities as energy levels improve.
• Follow-up blood tests ensure platelet counts and other parameters have normalized before discharge.

Important treatment considerations:

• Early recognition of warning signs and appropriate escalation of care significantly reduce mortality from severe dengue.
• Avoid aspirin, ibuprofen, and other non-steroidal anti-inflammatory drugs (NSAIDs) as these interfere with platelet function and increase bleeding risk. Acetaminophen is the only recommended antipyretic.
• Intramuscular injections should be avoided due to bleeding risk.
• Antibiotics are not indicated unless bacterial infection is documented, as dengue is viral.
• No herbal medicines or supplements have proven efficacy in treating dengue and should not replace standard medical care.
• Self-medication should be avoided; all medications should be taken under medical supervision.

5. Home Remedies and Natural Approaches for Dengue

While dengue requires proper medical management and monitoring, certain home care measures and natural approaches may support recovery and symptom relief when used alongside standard medical treatment. These measures should never replace medical care, especially in suspected severe dengue cases.

Hydration strategies:

• Maintaining excellent hydration is the most critical home care measure for dengue patients. Inadequate fluid intake is a major factor contributing to complications.
• Water should be consumed frequently in small quantities throughout the day. Room temperature water is generally better tolerated than very cold water, which may trigger nausea.
• Coconut water provides excellent hydration along with natural electrolytes including potassium, sodium, and magnesium. Fresh coconut water is preferable to packaged varieties. It also provides quick energy through natural sugars and has a cooling effect that many fever patients find soothing.
• Oral rehydration solutions containing balanced electrolytes help replace losses from fever, sweating, and vomiting. Homemade ORS can be prepared by mixing 6 teaspoons of sugar and half teaspoon of salt in 1 liter of clean water.
• Herbal teas consumed warm or at room temperature provide hydration while potentially offering other benefits. Options include ginger tea (may help reduce nausea), tulsi (holy basil) tea, chamomile tea, and lemongrass tea.
• Fresh fruit juices from oranges, pomegranates, apples, and other fruits provide hydration, vitamins, natural sugars for energy, and antioxidants. Dilute juices if they are too concentrated or sweet, as this may worsen nausea.
• Vegetable soups and broths provide hydration, electrolytes, and nutrients while being easy to digest. Clear soups are generally better tolerated during acute illness than heavy, creamy varieties.

Foods traditionally used to support recovery:

• Papaya leaf extract has been traditionally used in dengue-endemic regions and has generated significant interest. Some preliminary studies suggest it may help increase platelet counts, though evidence remains limited and inconsistent.
• Fresh papaya leaves are crushed or ground to extract juice, typically 2 tablespoons taken 2-3 times daily. The extremely bitter taste makes it difficult for many patients to consume. Commercial papaya leaf extract capsules are also available.
• Important: While some patients and healthcare providers report benefits, scientific evidence is not conclusive. Papaya leaf should complement, not replace, standard medical treatment and monitoring.
• Giloy (Tinospora cordifolia), an herb used in Ayurvedic medicine, is believed to support immune function and reduce fever. It can be consumed as juice, powder mixed with water, or in capsule form. However, scientific validation of its efficacy specifically for dengue is lacking.
• Tulsi (holy basil/Ocimum sanctum) leaves are traditionally chewed or made into tea. They are believed to have antipyretic, immune-supporting, and anti-inflammatory properties, though specific benefits for dengue remain unproven.
• Fenugreek seeds soaked overnight and consumed as tea are traditionally believed to reduce fever and promote restful sleep in some cultures.

Nutritional support during illness:

• Small, frequent meals are better tolerated than large meals when appetite is poor and nausea is present. Eating something every 2-3 hours, even if just a few bites, helps maintain energy levels.
• Easy-to-digest foods including plain rice, khichdi (rice and lentil porridge), bananas, toast, crackers, boiled vegetables, and light soups are less likely to worsen nausea and are gentler on the digestive system.
• Protein sources such as eggs, lean chicken, fish, lentils, and yogurt help maintain strength and support immune function, though heavy protein meals may be difficult to digest during acute illness.

Rest and symptom management:

• Adequate rest in a cool, comfortable environment allows the body to direct energy toward fighting infection. Physical exertion should be minimized during the acute illness phase.
• Cool compresses applied to the forehead, neck, and body help reduce fever and provide comfort. Lukewarm sponge baths can also help bring down high fever. Avoid very cold water or ice, which may cause shivering and actually increase body temperature.
• Mosquito protection is essential even after diagnosis to prevent transmission of the virus to mosquitoes that might bite the patient, perpetuating the transmission cycle. Patients should rest under mosquito nets, use mosquito repellents, and ensure screens on windows and doors.
• Comfortable, loose-fitting clothing made from breathable fabrics like cotton helps with temperature regulation and comfort.

Managing specific symptoms:

• For nausea and vomiting, ginger tea or ginger in small amounts may help. Eating small amounts of bland foods, avoiding strong smells, and staying upright after eating can reduce nausea. If vomiting persists, medical attention is necessary for intravenous hydration.
• For headache and body pain, acetaminophen (paracetamol) is the only safe pain reliever. Cold compresses may provide additional comfort.
• For poor appetite, foods with appealing aromas and flavors (while still being gentle on the stomach) may stimulate appetite. Small portions reduce the overwhelming feeling of facing a large meal.

Monitoring at home:

• Maintaining a symptom diary helps track disease progression and identify warning signs early. Record temperature, fluid intake and output, severity of symptoms, presence of bleeding, and any concerning changes.
• Daily temperature monitoring helps track fever patterns. Take temperature at least three times daily.
• Watch for warning signs including persistent severe abdominal pain, continuous vomiting, bleeding from any site, extreme weakness or restlessness, difficulty breathing, cold or clammy skin, or decreased urination. Any of these requires immediate medical attention.

Important considerations:

• Home care is appropriate only for patients with uncomplicated dengue who have been medically evaluated and do not have warning signs. Regular medical follow-up is essential.
• Natural remedies and traditional approaches lack robust scientific evidence for dengue treatment. They should be viewed as complementary measures, not primary treatments.
• Never delay seeking medical care if symptoms worsen or warning signs appear, regardless of any home remedies being used.
• Avoid self-medication with any drugs except acetaminophen for fever unless prescribed by a doctor. Many medications can worsen dengue complications.
• Patients should maintain contact with healthcare providers and follow their specific recommendations for monitoring and follow-up.

6. Diet Recommendations for Dengue

Nutrition plays a supportive role in dengue recovery by maintaining hydration, providing energy, supporting immune function, and promoting healing. While diet cannot cure dengue, appropriate food choices help manage symptoms and support the body during illness and recovery.

Nutritional principles during dengue:

• Hydration through fluids and fluid-rich foods takes absolute priority throughout dengue illness. Dehydration is a major risk factor for complications.
• Easily digestible foods reduce the burden on the digestive system, which may be affected by dengue. Complex, heavy, or spicy meals can worsen nausea and digestive discomfort.
• Small, frequent meals and snacks maintain blood sugar levels and provide steady energy without overwhelming the digestive system. Eating every 2-3 hours is often better tolerated than three large meals.
• Nutrient-dense foods provide maximum nutritional value even in small quantities when appetite is reduced.

Recommended foods and beverages:

• Fluids should be consumed abundantly throughout the day. Water is essential, with at least 3-4 liters daily for adults, adjusted based on body size, fever, and fluid losses. Coconut water provides excellent hydration with natural electrolytes and is particularly refreshing for fever patients. Fresh fruit juices from oranges, pomegranates, watermelon, and apples supply vitamins, antioxidants, and fluids. Herbal teas including ginger, tulsi, chamomile, and lemongrass offer hydration and potential symptom relief. Clear broths and vegetable soups provide fluids, electrolytes, and easily absorbed nutrients.
• Fruits rich in vitamin C and antioxidants support immune function and recovery. Oranges, sweet limes, guavas, kiwis, strawberries, and papaya provide vitamin C. Pomegranate is traditionally valued for potential benefits on platelet counts, though scientific evidence is limited. Watermelon provides excellent hydration along with nutrients. Bananas are gentle on the stomach, provide quick energy, and contain potassium. Soft, ripe fruits are easier to digest than unripe or very fibrous varieties.
• Vegetables should be included as tolerated, preferably well-cooked to ease digestion. Leafy greens including spinach, fenugreek leaves, and lettuce provide folate, iron, and vitamins. Carrots, pumpkin, and sweet potatoes offer beta-carotene and are easily digestible. Bottle gourd, ridge gourd, and bitter gourd are traditional choices in many dengue-endemic regions. Tomatoes provide vitamins and antioxidants. Vegetables should be steamed, boiled, or made into soups rather than fried.
• Protein sources maintain strength and support immune function. Eggs are excellent protein sources that are versatile and easily digestible. Lean chicken or fish in soup or boiled form provide protein without heavy fats. Lentils and legumes cooked until very soft (as in khichdi or dal) offer protein and iron. Yogurt provides protein and probiotics and is cooling and soothing. Milk can be consumed if tolerated, preferably low-fat varieties.
• Whole grains provide energy and nutrients. Rice, especially when cooked soft, is gentle on the stomach. Khichdi (rice and lentil porridge) is a traditional comfort food that is easily digestible and nutritious. Oatmeal provides soluble fiber and sustained energy. Whole wheat bread or crackers offer carbohydrates and are usually well-tolerated. These should be cooked until soft for easier digestion.
• Foods with specific traditional uses include papaya leaves (as discussed in home remedies section), raw papaya fruit which contains enzymes that may aid digestion, fenugreek leaves and seeds traditionally believed to reduce fever, and kiwi fruit which is rich in vitamin C and other nutrients.

Foods to avoid or limit during dengue:

• Spicy and heavily seasoned foods irritate the digestive system and may worsen nausea, cause discomfort, and are generally poorly tolerated during fever. Avoid hot peppers, excessive black pepper, strong spices, and very salty foods.
• Fried and fatty foods are difficult to digest, may worsen nausea, can cause bloating and discomfort, and divert energy to digestion that is needed for recovery. Avoid deep-fried foods, heavy curries with excessive oil, fatty meats, and rich, creamy dishes.
• Very cold or very hot foods and beverages may trigger discomfort or worsen nausea. Room temperature or lukewarm options are generally better tolerated. Avoid ice-cold drinks, ice cream during acute illness, and very hot beverages.
• Caffeinated beverages including coffee, strong tea, cola drinks, and energy drinks may contribute to dehydration, cause stomach irritation, interfere with rest, and potentially affect platelet function. Limit or avoid these during dengue illness.
• Alcohol must be completely avoided as it causes dehydration, impairs immune function, may interact with medications, can worsen liver stress, and potentially increases bleeding risk.
• Processed and junk foods including packaged snacks, fast food, candy and sweets in excess, and artificial beverages provide poor nutrition, may contain additives that stress the system, are often high in unhealthy fats and salt, and can worsen digestive symptoms.
• Raw or undercooked foods carry infection risks when the immune system is compromised. Avoid raw seafood, undercooked eggs or meat, unpasteurized dairy products, and unwashed raw vegetables during illness. All foods should be properly cooked and fresh.
• High-fiber foods that are difficult to digest may cause bloating and discomfort during acute illness. Limit whole grains with tough bran, raw cruciferous vegetables, and beans that may cause gas. These can be reintroduced during recovery.
• Acidic foods in excess may cause stomach irritation in some patients, though citrus fruits in moderation are beneficial for vitamin C. Monitor individual tolerance.

Dietary strategies for specific symptoms:

• For nausea and vomiting, eat bland foods like crackers, toast, rice, and bananas. Consume cold or room temperature foods which may be better tolerated. Eat slowly in very small amounts. Ginger tea or small pieces of ginger may help. Avoid strong food smells that may trigger nausea.
• For poor appetite, present food attractively in small portions. Include favorite foods when possible (if they are appropriate for dengue). Smoothies or shakes can provide nutrients in liquid form. Don't force eating, but encourage small amounts frequently.
• For diarrhea if present, increase fluids to prevent dehydration. Stick to bland, binding foods like rice, bananas, and toast. Avoid fatty, spicy, or high-fiber foods temporarily.
• For constipation during recovery, gradually increase fiber intake through cooked vegetables and fruits. Ensure adequate fluid intake. Gentle movement or walking as energy permits may help.

Dietary considerations during recovery:

As appetite returns, gradually increase portion sizes and variety. Continue emphasizing nutrient-dense foods to replenish nutrient stores depleted during illness. Maintain excellent hydration even after fever resolves. Include iron-rich foods to address any anemia from blood loss or bone marrow suppression. Foods rich in vitamin B12, folate, and protein support blood cell production during recovery.

Important dietary considerations:

• No specific food or diet can cure dengue or significantly alter its course. Diet serves a supportive role alongside proper medical management.
• Individual tolerance varies. Some foods may be well-tolerated by one patient but worsen symptoms in another. Pay attention to personal responses.
• Cultural and personal food preferences should be respected when possible, adapting recommendations to familiar, comforting foods that meet nutritional needs.
• Food safety is paramount during illness when immunity is compromised. All foods should be freshly prepared, properly cooked, and hygienically handled.
• Supplements are not typically necessary if a varied diet is consumed. However, if a healthcare provider recommends specific supplements based on laboratory findings or individual needs, follow their guidance.
• Pediatric and elderly patients may have different nutritional requirements and tolerances. Dietary approaches should be appropriately adjusted for age.

7. Medications Available to Treat Dengue

Currently, no specific antiviral medication exists to directly treat dengue virus infection. Management relies on supportive medications that address symptoms, prevent complications, and support the body while the immune system clears the infection. Understanding appropriate and inappropriate medications is crucial for safe dengue management.

Antipyretics (fever reducers):

• Acetaminophen, also known as paracetamol, is the only recommended antipyretic for dengue fever. It reduces fever and relieves headache and body pain without affecting platelet function or increasing bleeding risk.
• Adult dosing: 500-1000 mg every 4-6 hours as needed, with a maximum of 4000 mg (4 grams) in 24 hours. Lower maximum doses (2000-3000 mg daily) are recommended for patients with liver disease or chronic alcohol use.
• Pediatric dosing: 10-15 mg per kilogram of body weight every 4-6 hours as needed, not exceeding 5 doses in 24 hours. Liquid formulations with appropriate dosing syringes ensure accurate administration for children.
• Acetaminophen is available in various formulations including tablets, capsules, liquid suspensions for children, and dissolvable tablets. It can be taken with or without food, though taking with food may reduce stomach irritation.
• Important: While acetaminophen is generally safe, excessive doses can cause severe liver damage. Never exceed recommended doses or combine multiple acetaminophen-containing products, as many cold and flu preparations contain acetaminophen along with other ingredients.

Medications to absolutely avoid in dengue:

• Aspirin (acetylsalicylic acid) must never be used in dengue. It inhibits platelet function, increases bleeding risk significantly, and may precipitate Reye's syndrome in children and adolescents.
• Non-steroidal anti-inflammatory drugs (NSAIDs) including ibuprofen, naproxen, diclofenac, mefenamic acid, and similar drugs must be strictly avoided. These medications interfere with platelet function, increase bleeding risk, may cause gastric irritation or ulceration potentially leading to gastrointestinal bleeding, can affect kidney function which may already be compromised in severe dengue, and may mask warning signs by artificially reducing fever.
• Corticosteroids (steroids) are not beneficial in dengue and may actually be harmful. They do not reduce disease severity or mortality, may worsen outcomes in some cases, suppress immune function, and increase infection risks. They should only be used if specific medical indications exist that are unrelated to dengue.
• Intramuscular injections should be avoided due to bleeding risk associated with thrombocytopenia. Medications should be given orally or intravenously when necessary.

Antiemetics (anti-nausea medications):

• When nausea and vomiting are severe and prevent adequate oral fluid intake, antiemetic medications may be necessary.
• Ondansetron is commonly used and generally safe. It can be given as oral dissolving tablets (4-8 mg every 8 hours) or intravenously if vomiting is too severe for oral administration. Side effects are generally mild but may include headache or constipation.
• Metoclopramide (5-10 mg every 6-8 hours) is another option that also promotes gastric emptying. It should be used cautiously in young patients due to risk of movement disorders.
• Domperidone may be used in some regions, though it is not available in all countries.
• Antiemetics should be used judiciously and are not routinely given unless nausea significantly impairs oral intake or quality of life.

Intravenous fluids:

• While not a "medication" in the traditional sense, intravenous fluids are the most critical therapeutic intervention for dengue patients with warning signs or severe dengue.
• Isotonic crystalloid solutions including 0.9% normal saline, Ringer's lactate, or Hartmann's solution are used for fluid resuscitation and replacement of plasma losses.
• The rate and volume of IV fluids are carefully calculated based on patient weight, clinical status, and laboratory parameters. Standardized protocols guide fluid management to achieve adequate tissue perfusion while avoiding fluid overload.
• Dextrose-containing fluids may be added if blood sugar is low, particularly in children.

Blood products:

• Platelet transfusions are reserved for specific circumstances and are not routinely given for low platelet counts alone. Indications include platelet count below 10,000-20,000 cells/μL with active bleeding, platelet count below 50,000 cells/μL with major bleeding or before necessary surgical procedures, and suspected platelet dysfunction with significant bleeding despite higher counts.
• Prophylactic platelet transfusions (giving platelets just because the count is low without bleeding) are generally not recommended as they have not been shown to prevent bleeding or improve outcomes in stable patients.
• Fresh frozen plasma may be given for severe bleeding with coagulation abnormalities or before invasive procedures when coagulation parameters are significantly deranged.
• Packed red blood cells are transfused if significant blood loss has caused symptomatic anemia or hemodynamic instability.
• Whole blood may be used in resource-limited settings when component therapy is unavailable.

Medications for complications:

• Antibiotics are only indicated if bacterial superinfection is documented or strongly suspected. Dengue itself is viral and does not respond to antibiotics. Inappropriate antibiotic use contributes to antimicrobial resistance and may cause side effects without benefit.
• Diuretics may be necessary during the recovery phase if reabsorbed fluid causes volume overload, particularly in patients with cardiac or renal disease. Furosemide is most commonly used, with careful monitoring of electrolytes and kidney function.
• Vasopressors and inotropic agents may be required in intensive care settings for patients with profound dengue shock that doesn't respond adequately to fluid resuscitation. These include dopamine, dobutamine, epinephrine, or norepinephrine, administered under close hemodynamic monitoring.

Experimental and investigational treatments:

• No antiviral drugs have been proven effective for dengue treatment, though research continues. Several candidates are under investigation in clinical trials but none are currently approved for clinical use.
• Immunomodulatory agents and other therapeutic approaches remain experimental.
• Traditional or herbal medicines lack robust scientific evidence for efficacy in dengue. While some may be traditionally used, they should not replace standard medical care and should only be used after discussing with healthcare providers.

Preventive medications - Dengue vaccine:

• Dengvaxia (CYD-TDV) is a live attenuated tetravalent dengue vaccine approved in several countries for individuals aged 9-45 years who have documented previous dengue infection and live in endemic areas. The vaccine is administered as three doses given at 0, 6, and 12 months.
• Important point: This vaccine is only recommended for people with previous laboratory-confirmed dengue infection, as it may increase the risk of severe dengue in those who have never been infected (seronegative individuals).
• Qdenga (TAK-003) is another live attenuated tetravalent dengue vaccine that has been approved in several countries for individuals aged 4 years and older, regardless of previous dengue exposure. It is administered as two doses given three months apart.
• Vaccine availability and recommendations vary by country and region. Consult local health authorities and healthcare providers for specific guidance.

Supportive medications that may be used:

• Proton pump inhibitors or H2 blockers such as omeprazole or ranitidine may be used to reduce gastric acid production if significant nausea or risk of gastric bleeding is present.
• Antihistamines like diphenhydramine may occasionally be used if allergic reactions to mosquito bites or medications occur, though sedating antihistamines should be used cautiously as they may mask changes in consciousness.

Important medication considerations:

• Self-medication should be avoided. All medications, even over-the-counter drugs, should be taken only under medical supervision during dengue illness.
• Inform healthcare providers of all medications being taken, including supplements, herbal preparations, and medications for other conditions, to avoid interactions and identify drugs that may need adjustment during dengue illness.
• Medication needs may change as the disease progresses. Initial symptoms may require only acetaminophen and oral fluids, while progression to severe dengue requires intensive interventions.
• Follow prescribed dosing schedules precisely. For acetaminophen in particular, spacing doses appropriately prevents both under-treatment of symptoms and risk of overdose.
• Never share prescription medications with others, even if they have similar symptoms.
• Store medications properly according to label instructions, keep them out of reach of children, and check expiration dates.
• If any adverse reactions to medications occur, report them to healthcare providers immediately.

Note:

•  This information about dengue provides educational content for understanding, preventing, and managing this important tropical disease. Prevention through mosquito control, early recognition of symptoms, appropriate medical management, and close monitoring for complications are essential for reducing dengue morbidity and mortality. Always consult qualified healthcare professionals for personalized medical advice, accurate diagnosis, and evidence-based treatment plans tailored to individual circumstances. While supportive measures and appropriate nutrition aid recovery, they should complement rather than replace professional medical care for dengue infection. In endemic areas, community participation in mosquito control through elimination of breeding sites is crucial for preventing dengue transmission.