Dengue: Everything you should know
Dengue or dengue fever is a mosquito-borne viral infection that presents with high fever and flu-like symptoms. The symptoms can range from mild to severe. This infection is common in tropical and subtropical regions of the world. Currently, there are no vaccines available for dengue. Thus, the best way to prevent the infection by avoiding mosquito bites.
Dengue can be caused by any one of the four types of dengue viruses (DENV). These viruses are usually spread by a mosquito species known as Aedes aegypti.
Dengue infection can be passed from human to human through infected mosquito bites. When a mosquito bites an individual infected with the dengue virus, the virus is passed on to the mosquito, which then bites another person, and causes the infection.
Anyone can have dengue more than once; a second infection is associated with a higher risk of developing severe dengue fever.
Signs and Symptoms
The symptoms of dengue vary based on the severity of the infection.
Symptoms of mild dengue:
- high fever - 104 F (40 C)
- intense headache
- muscle, bone or joint pain
- pain behind the eyes
- body rash that may disappear and then reappear
- nausea and vomiting
- swollen glands
Most individuals recover within a week. Sometimes, the symptoms can worsen to severe dengue. The indications of severe dengue include:
- Severe stomach pain
- Persistent vomiting
- Difficult or rapid breathing
- Bleeding from gums or nose
- Blood in urine, stools or vomit
- Bleeding under the skin, which may appear like bruising
- Irritability or restlessness
If severe dengue happens, blood vessels get damaged and leaky, and the platelet count (the number of clot-forming cells) in the blood reduces. This can lead to internal bleeding, shock, organ failure and death.
The risk of dengue fever or severe form of the infection is associated with:
- Living or traveling in tropical and subtropical areas; high-risk areas include western Pacific islands, Southeast Asia, Latin America and Africa.
- Previous infection with dengue fever.
Complications of severe dengue include:
- internal bleeding
- organ damage
- extremely low blood pressure
Dengue during pregnancy may spread from the mother to the baby during childbirth. Moreover, these babies are at a high risk of pre-term birth, low birth weight or fetal distress.
The signs and symptoms of dengue can be confused with those of chikungunya, malaria, typhoid fever and Zika virus, hence making the diagnosis difficult.
Provide a detailed medical history and travel history to your doctor. A blood sample may be drawn to test for the evidence of infection with one of the dengue viruses in the laboratory.
As dengue is a viral infection, no specific treatment or cure exists. However, some interventions can help manage the condition better. For mild dengue, treatment includes:
- Preventing dehydration by drinking enough clean water
- Taking painkillers, such as paracetamol to reduce fever and ease pain.
Other over-the-counter pain medicines, such as aspirin, ibuprofen and naproxen sodium should be avoided, as these can increase the risk of bleeding complications.
For severe dengue, treatment may include:
- Intravenous fluid supplementation, if the person cannot take fluids by mouth
- Supportive care in a hospital
- Blood transfusion
- Blood pressure monitoring
Preventing mosquito bites
There are several ways to prevent mosquito bites while visiting or living in high-risk areas:
- Wear long pants, long-sleeved shirts, socks, and hat; tuck pant legs into shoes or socks to reduce the amount of skin exposure.
- Use mosquito repellents with ≥10% concentration of diethyltoluamide (DEET) based on the lengths of exposure. Do not use DEET on young children.
- Use mosquito nets treated with insecticides as they will be more effective in killing the mosquitoes and other insects.
- Do no use heavily scented soaps and perfumes, as they may attract mosquitoes.
- Avoid being outside at dawn, dusk, and early evening.
- Do not let water stagnate around your residence, as the Aedes mosquito breeds in clean, stagnant water.
Frequently asked questions (FAQs)
Can I take non-steroidal anti-inflammatory drugs (NSAIDs) for body pains associated with dengue?
Non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin or ibuprofen, should be avoided in individuals with dengue, as they can increase the risk of internal bleeding.
What are the symptoms of dengue hemorrhagic fever and dengue shock syndrome?
In some cases, the symptoms of dengue can worsen to severe dengue, dengue hemorrhagic fever or dengue shock syndrome.
An individual with dengue hemorrhagic fever may present:
- Damage to lymph and blood vessels
- Bleeding from the mouth, gums, or nose
- Internal bleeding, which can lead to black vomit and/or stools
- Clammy skin
- A lower number of platelets in the blood
- Sensitive stomach
- Small blood spots under the skin
- Weak pulse
Dengue shock syndrome is a severe form of dengue, which can be fatal. A patient with dengue shock syndrome may experience:
- Intense stomach pain
- Sudden hypotension, or a fast drop in blood pressure
- Blood vessels leaking fluid
- Heavy bleeding
- Regular vomiting
Without treatment, both dengue hemorrhagic fever and dengue shock syndrome can be fatal.
After being diagnosed with dengue, how will you know if you are dehydrated?
During dengue, high fever and vomiting can dehydrate the body. Some of the signs of dehydration include:
- Dry mouth or lips
- Decreased urination
- Lethargy or confusion
- Few or no tears
- Cold or clammy extremities
Dr Ashwin Karuppan V
M.B.B.S, M.D (Internal Medicine)
Department of Internal Medicine, Critical Care & Diabetology