Dengue, a mosquito-borne disease, is prevalent in areas with tropical and subtropical climate. According to the Centers for Disease Control and Prevention, this infection is common in more than 100 countries around the world. The estimate of this world body suggests that around 3 billion people live in dengue-prone areas. These include India and other parts of South East Asia, China, Africa, Taiwan and Mexico among others. In 2019 alone, India saw more than 67,000 cases of dengue, suggest the figures released by the National Vector Borne Disease Control Programme (NVBDCP). This report also reveals that 2017 was the worst year for India in terms of dengue with 1.88 lakh cases and 325 deaths.
What is Dengue?
Dengue refers to a mosquito-borne viral infection characterised by high grade fever, headache, muscle and joint pain, and skin rashes. Transmitted through the bite of Aedes mosquitoes, this infection is caused by four closely-related serotypes of a virus of the Flaviviridae family: DENV-1, DENV-2, DENV-3 and DENV-4. Though these viruses are self-limiting and don’t last for more than 10 days, the infection, in severe form, can cause dengue haemorrhagic fever (DHF). This condition leads to heavy bleeding, a sudden drop in blood pressure platelet (clot-forming cells) count in the blood and even death. This is the final stage of DHF and is known as Dengue shock syndrome (DSS). In extreme cases, immediate hospitalisation is required. There is no specific treatment for dengue. The approach is that of symptom control.
Dengue fever can be both mild or severe. The symptoms also vary accordingly. Many, especially kids and teens, may not even experience the manifestations of dengue if it is mild. The symptoms of mild form of this condition set in four to seven days after being infected and subside within a week. They include high grade fever (104°F) and at least two of the following:
- Muscle, bone and joint pain
- Pain behind the eyes
- Swollen glands
However, in severe cases, dengue can progress to DHF, a health emergency. In this condition, blood vessels are damaged and platelet count in the blood drops. The symptoms of this condition include:
- Severe abdominal pain
- Persistent vomiting
- Bleeding from your gums or nose
- Blood in your urine, stools or vomit
- Bleeding under the skin, which might look like bruising
- Difficult or rapid breathing
- Cold or clammy skin (shock)
- Irritability or restlessness
What Causes Dengue?
As already mentioned, dengue is caused by of Aedes mosquitoes. Various factors can increase your risk of being infected by this viral infection. Here, we shed light on a few of them:
Living in a dengue-prone area: If you live in an area infested with Aedes mosquitoes, your chance of getting infected by dengue increases naturally.
Prior infection: Being infected by dengue doesn’t make you immune to this viral infection. In fact, it may hit you harder the next time.
Low immunity: People with compromised immunity are more likely to suffer from dengue. This is what makes the elderly population vulnerable to this condition all the more. Certain conditions like diabetes, lung diseases and cardiovascular ailments can also up your risk.
Low platelet count: A severe complication of dengue is low platelet (clot-forming cells) count in the blood. So, if you already have depleted levels of platelet, you are likely to catch this infection faster than others.
If a dengue infection is severe, it can affect your lungs, liver and heart. Blood pressure can drop dangerously triggering shock. In extreme cases, it may be fatal too. Here is what happens to the body if this infection is severe:
- Severe pain in the abdomen
- Fluid accumulation in the liver
- Fluid accumulation in the chest
Diagnosis of Dengue
The diagnosis of dengue is usually done based on a patient’s symptoms and physical examination, especially in endemic areas. Your doctor may suggest the following tests after evaluating your symptoms:
Complete Blood Count-This test reveals your platelet count. Low count of these cells is a crucial marker of dengue.
ELISA test for dengue NS1 Ag-This is a confirmatory blood test which detects the dengue virus antigen. However, it may show negative results during the initial stages of infection. So, this test may need to be repeated if symptoms persist.
PCR for detecting viral DNA-This test can be more effective in the first 7 days of infection, when NS1 Ag test may show negative results despite the infection.
Serum IgG and IgM test-This test helps in the diagnosis of the condition at a later stage. Once the virus sneaks into the body, the immune cells start producing antibodies IgG and IgM against the dengue virus. The level of these antibodies increases gradually. This test is a useful indicator of a prior infection.
Treatment of Dengue
There is no specific medicine for dengue since it is a viral disease. However, your doctor may suggest a pain or fever reliever like paracetamol to control the symptoms. Another important aspect of dengue control is keeping yourself hydrated. So, drinking plenty of clean water is necessary. However, people with severe symptoms may need hospitalisation. In an extreme case, one may need intravenous fluid or electrolyte supplementation, constant blood pressure monitoring and even blood transfusion. But drugs such as aspirin or ibuprofen should not be taken since they can increase the risk of bleeding.
A healthy, well-planned diet will help in the fast recovery of dengue fever. Make sure your meals are easy to digest as the performance of your gastrointestinal tract may be sluggish during this condition. While adding some foods to your diet may relieve symptoms, eliminating some will help.
Add papaya leaf juice to your diet: It can help in the healing process by taking up your platelet count and boosting your immunity. Have it twice or thrice a day with water.
Have coconut water: It will keep you hydrated and nourish your body. Having two glasses of coconut water will improve your overall health.
Include neem leaves in your meals: They come with chemicals named nimbin and nimbidin, which are endowed with anti-inflammatory, anti-pyretic and anti-microbial properties. They are also known to increase your platelet count.
Avoid these foods: Although there is no strict no-no, caffeinated beverages, spicy and deep-fried foods are best avoided. Oily and spice-laden foods won’t be easy for your stomach to digest while you are suffering from dengue. Caffeinated beverages, on the other hand, will dehydrate you.
Prevention of dengue
In May 2019, the US Food and Drug Administration approved a dengue vaccine named Dengvaxia for use only in kids in the age bracket of 9 to 16 years with a history of the infection. However, it is not yet approved for use in India. Dengue is a communicable disease spread by mosquitoes from one human to another. So, the only way it can really be prevented in the absence of a vaccine is by avoiding mosquito bites. So, you have to rely on mosquito repellents, mosquito nets, net screens on your doors and windows, and clothes that cover you well (long-sleeve shirts, full-sleeve trousers,etc.). Here are some other measures you can employ:
- Make sure all egg-laying habitats of mosquitoes like open and stagnant water source are cleaned up.
- If there are any open water sources you cannot eliminate, cover them and apply appropriate insecticides.
- Use air conditioners when indoors.
The content has been verified by Dr Amitabh Parti, Director, Internal Medicine, Fortis Memorial Research Institute, Gurugram.