Dengue or dengue fever is the most common viral infection spread to humans through the bite of Aedes mosquitoes. Around half of the world’s population in over 132 countries residing in tropical and subtropical regions is at risk of contracting dengue.
Dengue virus (DENV) infects up to 400 million people yearly and causes 40,000 deaths globally.
If you are diagnosed with dengue, you may have symptoms such as high-grade fever (104°F), headache, muscle and joint pains, eye pain (usually behind the eyes), swollen glands, nausea and vomiting. You may develop a rash a few days after the fever begins.
Most affected people have no or mild symptoms and get better in a few days. However, some people, around 1 in 20 get severe dengue and need immediate treatment in the hospital.
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Why is it important to recognize the warning signs of dengue?
You should be able to recognize the warning signs of dengue fever as it can become life-threatening severe dengue. Severe dengue may result in complications such as internal bleeding, organ damage, shock and even death. If left untreated, dengue may have a mortality rate of up to 20% which can be reduced to around 1% with the right treatment.
According to the World Health Organization (WHO), the warning signs of dengue are severe abdominal pain, persistent vomiting, bleeding, liver enlargement, extreme lethargy, and fluid accumulation which manifests as trouble breathing and swollen abdomen. Laboratory findings indicate rising haematocrit levels and decreasing platelet levels.
Warning signs of dengue
In 1997, the World Health Organization (WHO) classified dengue into undifferentiated fever, dengue fever (DF), and dengue hemorrhagic fever (DHF). However, the new WHO dengue guidelines in 2009 categorize dengue as:
- Dengue without warning signs
- Dengue with warning signs
- Severe dengue
This updated system aims to simplify the identification of severe cases.
Dengue can become dangerous because it causes leaky and damaged blood vessels allowing fluid to leave from blood vessels. It also decreases platelets which result in bleeding tendencies. If enough fluid exits from the circulation, it may lead to shock. Shock is a medical emergency in which the organs in the body are not getting enough blood to function properly.
This is why dengue treatment is focused on ensuring the body has enough fluids.
Immediately visit a hospital if you have the following warning signs of dengue after your fever settles.
1) Intense abdominal pain or tenderness
Abdominal pain may be caused by inflammation of organs inside the abdomen.
Patients with dengue might be diagnosed with other diseases causing abdominal pain such as acute viral hepatitis, typhoid, stomach ulcer, acute pancreatitis or gallbladder diseases.
Your doctor will look for the cause of abdominal pain.
2) Persistent vomiting
The Centers for Disease Control and Prevention (CDC) defines persistent vomiting as three or more episodes within 24 hours.
Frequent vomiting can lead to severe dehydration and electrolyte imbalance due to large amounts of fluids leaving the body. Some signs of dehydration include decreased urination, dry mouth or lips and lethargy. Children are at a greater risk of dehydration as they cannot communicate their thirst properly, and their bodies are not as adept at countering dehydration.
Seek medical care if you or your child experiences persistent vomiting.
3) Difficulty in breathing
The accumulation of fluid between the two layers that surround the lungs (pleural effusion) can cause you trouble breathing as it restricts the lungs from expanding fully. You may also feel like you are breathing too fast.
These signs warrant immediate medical attention.
4) Swollen abdomen
Abdominal swelling (ascites) is the build-up of fluid in the abdomen. This is another sign of fluid accumulation in regions of the body where it normally should not. Fluid in the abdomen may cause you trouble breathing as the diaphragm is pushed upwards putting pressure on the lower lungs. Your abdomen can be a bit swollen due to bloating. A doctor will be able to determine if you have ascites.
5) Bleeding
Platelets are cells that help in stopping your bleeding. If they decrease a lot, bleeding can manifest in many ways such as:
- Bleeding gums
- Bleeding nose
- Blood in vomiting
- Bloody stools (caused by bleeding in the upper gastrointestinal tract (GI) such as the stomach)
- Black, tarry stools (caused by bleeding in the lower gastrointestinal tract such as the intestine)
- Blood in urine
- Vaginal bleeding
- Blood under the skin
In particular, you should watch out for blood in vomiting, bloody stools and black stools as these signs are highly suggestive of severe dengue.
Avoid taking any non-steroid anti-inflammatory (NSAIDs) such as ibuprofen, aspirin, or diclofenac as these drugs increase the risk of bleeding.
6) Extreme lethargy
Lethargy during dengue fever is common as your body is fighting an infection that affects multiple organs. However, extreme fatigue and restlessness may reflect a potentially severe internal problem. It may be also a sign of severe dehydration.
Do not ignore this symptom—seek medical attention promptly.
Additional warning signs detected in hospitals
Doctors and lab professionals can help identify the remaining two warning signs.
- Liver Enlargement: During an abdominal examination, a doctor can detect a liver enlargement by palpating your abdomen. An enlarged liver is a sign of inflamed liver.
- Abnormal blood test: A blood test called complete blood count (CBC) can tell about your hematocrit and platelet levels. Rising hematocrit levels indicate dehydration and decreasing platelet levels indicate a higher risk of bleeding.
Conclusion
Dengue affects millions of people worldwide. Many people get better on their own. However, some people can develop serious complications. It is important to know the warning signs of dengue and visit a doctor immediately. Your doctor will assess you and prescribe an appropriate treatment. Depending on your condition, you may be hospitalized.
It is recommended that you eat certain foods when you have dengue, and take protective measures to prevent the spread of dengue to your loved ones.
You may book a quick online consultation with a doctor if you are unsure whether you have warning signs.
Frequently asked questions (FAQs)
How is dengue diagnosed?
Your doctor will order a test depending on the day of your illness. Enzyme-linked immunosorbent assay (ELISA) may be used to detect dengue NS1 antigen, IgM and IgG antibodies made against the dengue virus. The dengue polymerase chain reaction (PCR) test is used to detect dengue virus in the blood.
Who is at risk of getting severe dengue?
The risk of severe dengue increases if you have other co-existing conditions. Pregnant patients, children and the older adults are vulnerable populations. Some people who get dengue for the second time also tend to get a severe form of dengue.
Which diseases can resemble dengue?
Dengue has similar features to influenza, measles, infectious diarrhea, appendicitis, malaria, typhoid and encephalitis (inflammation of the brain). Since dengue resembles many diseases, you should visit a doctor to get diagnosed, especially if people around you are getting dengue or you have a travel history.
What is the treatment of dengue?
Treatment varies for each patient. Dengue without warning signs is managed at home by drinking lots of fluid, taking fever and pain-reducing medications such as paracetamol, and resting.
References
- About Dengue | Dengue | CDC.
https://www.cdc.gov/dengue/about/index.html - Dengue and severe dengue.
https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue - Dengue Fever – StatPearls – NCBI Bookshelf.
https://www.ncbi.nlm.nih.gov/books/NBK430732/ - Dengue guidelines for diagnosis, treatment, prevention and control: new edition.
https://iris.who.int/handle/10665/44188 - Dengue haemorrhagic fever: diagnosis, treatment, prevention and control.
https://iris.who.int/handle/10665/41988 - Htun, T. P., Xiong, Z., & Pang, J. (2021). Clinical signs and symptoms associated with WHO severe dengue classification: a systematic review and meta-analysis. Emerging Microbes & Infections, 10(1), 1116–1128.
https://doi.org/10.1080/22221751.2021.1935327 - Khanna, S., Vij, J. C., D Singal, K., & Tandon, R. (2005). Etiology of Abdominal Pain in Dengue Fever.
https://iris.who.int/handle/10665/164137 - Symptoms of Dengue and Testing | Dengue | CDC.
https://www.cdc.gov/dengue/signs-symptoms/ - Vector-borne diseases.
https://www.who.int/news-room/fact-sheets/detail/vector-borne-diseases - Zerfu, B., Kassa, T., & Legesse, M. (2023). Epidemiology, biology, pathogenesis, clinical manifestations, and diagnosis of dengue virus infection, and its trend in Ethiopia: a comprehensive literature review. Tropical Medicine and Health, 51(1), 1–20.
https://doi.org/10.1186/S41182-023-00504-0
