With 18 days of heavy rain in August, Delhi has seen severe water-logging, leading to a surge in mosquito breeding and over 500 reported cases of dengue. The situation is not confined to the capital; Karnataka is facing a rapid increase in dengue fever, and similar spikes are seen in Kerala and Tamil Nadu.

National data shows that by April 2024, India had already recorded 19,447 dengue cases and 16 deaths. The numbers are likely higher now. Bangalore alone saw a 270% rise in online searches about dengue fever, highlighting the growing concern.

As monsoon rains continue to impact the country, understanding and preventing dengue fever has become crucial. This blog will inform you about the symptoms, causes, and prevention strategies to help you stay safe.

What is dengue fever?

Dengue fever is a viral illness common in tropical and subtropical areas, including many parts of India. 

The dengue virus, a member of the Flavivirus family, causes dengue fever. The virus has four known strains (DENV-1, DENV-2, DENV-3, and DENV-4), meaning a person can be infected up to four times, each by a different strain. The primary cause of dengue fever is the bite of an infected Aedes mosquito, particularly Aedes aegypti, which is the main carrier of the virus.

When a mosquito bites someone infected with the dengue virus, it picks up the virus from their blood. The virus multiplies within the mosquito, and after approximately a week, the mosquito can spread the virus to others through its bite. Dengue fever is more common during the rainy season when mosquitoes breed more quickly. Hence, mosquito control is crucial in preventing its spread. Knowing how dengue fever spreads can help protect yourself and those around you.

Dengue danger zones: Who's most at risk?

Multiple factors contribute to the risk of contracting dengue fever. Here's what you need to know:

• Geographic location: Living in or travelling to tropical and subtropical regions puts you at higher risk. These regions include the Caribbean, Central and South America, Southeast Asia, and the Indian subcontinent.
• Climate: The rainy season is prime time for dengue outbreaks, as stagnant water from rain provides ideal breeding grounds for Aedes mosquitoes.
• Urbanisation: Densely populated urban areas with poor sanitation and standing water are hotspots for mosquito breeding, increasing the likelihood of transmission.
• Previous infections: If you've had dengue fever before, you're at a higher danger of developing severe forms if infected again with a different strain of the virus.
• Children and travellers: Children in endemic areas and travellers with no prior exposure to the virus are particularly vulnerable, often facing more severe symptoms and complications.

Awareness of these critical factors is essential for taking the necessary precautions, especially if you live in or plan to visit areas where dengue fever is prevalent.

What are the symptoms of dengue fever?

It's essential to recognise the symptoms of dengue fever early so you can get the proper treatment quickly.  At first, dengue fever symptoms can look a lot like the flu, which might cause a delay in getting help.

The first stage of dengue fever usually involves a sudden high fever, often as high as 104°F (40°C), often accompanied by debilitating headaches, excruciating pain behind the eyes, and severe joint and muscle pain. Other common dengue fever symptoms include:

• Severe joint and muscle pain is why dengue is sometimes called "breakbone fever"
• Extreme tiredness: You might feel exhausted. The exhaustion can last for weeks, even after the fever disappears
• Nausea and vomiting
• Skin rash: A rash may appear a few days after the fever starts and spread throughout the body
• Mild bleeding: You might notice nosebleeds, bleeding gums, or easy bruising

Dengue fever often starts with flu-like symptoms but can become more severe, leading to dangerous conditions like dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). Watch out for severe warning signs that can appear after the fever drops, usually within 24-48 hours:

1. Severe belly pain
2. Frequent vomiting 
3. Fast breathing
4. Bleeding from the gums or nose
5. Feeling very tired or restless
6. Blood in your vomit or stool
7. Swelling in the body from fluid buildup

"It can be tricky to tell the difference between dengue and other monsoon diseases like malaria, typhoid, or hepatitis because their symptoms often overlap," says Mumbai-based physician, Dr Manan Mehta. "That's why we usually rely on lab tests, like the analysis of complete blood count (CBC) and other specific tests, to diagnose and distinguish between these illnesses.”

How do you confirm dengue at home?

While you can't definitively diagnose dengue fever at home, watching for symptoms like a sudden high fever, severe headache, and joint pain helps. If you suspect dengue fever symptoms, you must visit a healthcare provider for confirmation through a blood test.

Dengue fever is confirmed through blood tests that detect the presence of the virus, viral antigens, or antibodies. Tests like NS1 antigen test, RT-PCR, or IgM/IgG antibody tests are commonly used to confirm the diagnosis.

Fascinating insights about dengue

From hashtags to health alerts, social media has played a role in tracking dengue. 

Did you know that researchers have found an innovative way to track the spread of dengue fever using social media? By analysing millions of posts and tweets on platforms like Twitter and Facebook, they identified where people talked about dengue cases. They monitored specific keywords related to dengue in real-time, and they could map out the spread of the disease even before official health reports came in.

This approach allowed them to detect and predict outbreaks faster and more accurately, giving public health authorities crucial information on which to act. The study shows that social media isn't just for communication—it can be a powerful tool for spotting and managing disease outbreaks, helping to save lives, and improving public health.

How to prevent dengue fever?

Combining personal protective measures and community-level mosquito control efforts can help effectively prevent dengue fever. Here are some practical tips:

• Eliminate stagnant water: Mosquitoes breed in still water, so remove or regularly empty items like flower pots, buckets, coconut shells, and bird baths. Ensure that water storage containers are covered tightly.
• Use mosquito repellents: Apply insect repellents to exposed skin, especially during dawn and dusk, when Aedes mosquitoes are most active. Opt for repellents containing DEET, picaridin, or lemon eucalyptus oil for better protection.
• Wear protective clothing: Long-sleeved shirts, long pants, socks, and shoes can reduce the chances of being bitten. Consider treating clothes with permethrin for added protection.
• Install screens and use bed nets: Keep windows and doors closed or screened. If sleeping outdoors or in areas without screens, use a bed net to protect yourself from mosquito bites while you sleep.
• Use mosquito control products: Use mosquito coils, vaporisers, or plug-in insecticides indoors. In high-risk areas, fogging and larvicidal treatments can help reduce mosquito populations.

How is dengue fever treated?

Once dengue fever is contracted, there is no specific antiviral treatment. Staying well-hydrated is key to managing dengue fever symptoms. To prevent dehydration, drink fluids like water and oral rehydration solutions. Adequate rest and a nutritious diet are essential to help the body recover. Refrain from engaging in intense activities until you are completely healed. Regularly monitor symptoms and seek medical attention if there are signs of severe dengue, such as bleeding, persistent vomiting, or sudden abdominal pain.

What not to eat during dengue fever?

Refrain from foods that are difficult to digest or may exacerbate symptoms. 

"⁠Dengue hepatitis can result in severe nausea. Eat simple foods in small quantities. Have plenty of fluids in small sips," says Dr Manan Mehta. Stick to light, easily digestible meals like soups, boiled vegetables, and fruits rich in vitamin C.

Low platelet counts may be a major concern when battling dengue fever. Dragon fruit, high in vitamin C and antioxidants, supports immune health and recovery. Some studies suggest papaya leaf extract may stimulate platelet production during dengue recovery. However, these are supportive measures and may not always be effective alone. 

Stay vigilant and take action to prevent dengue

As dengue fever rises across India during the monsoon season, it is crucial to stay informed and take critical measures to safeguard yourself and your loved ones.

Recognising early symptoms, understanding how the disease spreads, and following preventive measures are key to staying safe. Stay alert, seek medical attention if needed, and follow the recommended guidelines to protect against dengue.