Dengue Fever 101: Causes, Symptoms, Diagnosis

Dengue fever is transmitted by four distinct but closely related dengue viruses and affects millions of people worldwide.

You get dengue fever when an Aedes aegypti female mosquito is infected with the dengue virus and bites you. Dengue fever causes severe muscle and joint pain and can be life-threatening. That is why it is also known as breakbone fever.

Dengue fever infects around 400 million people worldwide each year, of which about 100 million experience mild or severe symptoms.

It is more common in tropical regions such as Latin America, Africa, Western Pacific Islands, and Southeast Asia.

Key Takeaways

• Dengue fever is caused by a virus and transmitted through the bite of an Aedes mosquito.
• Symptoms of dengue fever vary, but usually include fever, headaches, pain in the joints, rash, or nausea.
• The diagnosis can be made by reviewing the symptoms you present and/or a blood test such as PCR or antibody tests.
• The use of early diagnosis and supportive care has been documented to reduce complications and promote recovery.

What Causes Dengue Fever?

The following are the common causes of dengue:

1. Dengue Virus

Dengue fever is caused by the dengue virus, which has four serotypes (DENV-1, DENV-2, DENV-3, and DENV-4). A person may be infected with one or more strains over their lifetime.

However, infection with one strain typically provides lifelong immunity to that strain. Still, it does not give immunity to the other three strains and predisposes a patient to severe dengue in subsequent infections.

2. Mosquito Bites (Aedes aegypti)

The primary source of transmission is through an infected mosquito (Aedes aegypti) bite. The mosquito is endemic to warm, humid places with stagnant water, which serves as the breeding ground.

These mosquitoes are typically more active in the early morning and late afternoon. When they bite a human that has been infected with the virus, they become carriers and can spread the virus to other humans.

3. Indirect Transmission

Dengue does not spread directly from person to person. Instead, when a mosquito bites a person who is infected with the dengue virus, it can carry the virus and infect someone else when it bites again. This cycle of transmission is what causes outbreaks in communities.

4. Travelling to Affected Areas

People who travel to regions where dengue is common (such as South Asia, Southeast Asia, Latin America, and parts of Africa) are at higher risk of exposure to the virus.

Travelers may unknowingly bring the virus back to areas where dengue is not usually present, potentially sparking new outbreaks if local mosquito populations are capable of spreading it.

Also Read: 8 Important Health Checkup Tests Everyone Should Get

What Are the Symptoms of Dengue?

The majority of people will have no signs or symptoms of a dengue infection in early stages. When signs and symptoms do occur, they can be confused for another illness, like the flu. They usually appear four to ten days after a bite from an infected mosquito.

Here are some signs you may have dengue:

1. High Fever

A sudden high fever (up to 104°F or 40°C) is one of the first symptoms of dengue and one of the most common. It lasts two to seven days and may be accompanied by chills.

2. Severe Headache

Dengue can also cause severe pain behind the eyes and in the forehead area that can be constant, gets worse with eye movement, and lasts a while.

3. Muscle, Joint, and Bone Pain

This symptom is so characteristic that dengue is often called “breakbone fever.” The pain can be very severe and involve the muscles and joints of the body.

4. Nausea and Vomiting

Many people have shown gastrointestinal symptoms of nausea, vomiting or discomfort in the abdomen while they have the infection.

5. Skin Rash

A skin rash may develop a few days after the onset of fever, usually on the chest and/or limbs. The rash can present as small red spots or patches, which tend to evolve into widespread reddening.

6. Fatigue and Weakness

Even after the fever resolves, many individuals who have had dengue feel particularly fatigued, weak, or heavy for many days or even weeks.

7. Bleeding

Occasionally, there may be evidence of mild bleeding, such as nose bleeds, bleeding gums, or easy bruising, that may indicate progression to severe dengue.

Dr. Muhammad Nouman Anjum, a Lahore-based general physician recommends visiting a hospital or clinic immediately if you notice symptoms such as persistent vomiting, severe abdominal pain, bleeding under the skin, or rapid breathing.

Diagnosis of Dengue Fever

Doctors can diagnose dengue infection if a blood test checks for the virus or antibodies to it. If you become ill after travelling to a tropical location, tell your doctor. After the blood tests have been done, they can tell you if the dengue infection is responsible for your symptoms.

1. Dengue Test

A dengue test, also known as a dengue NS1 Antigen test is the most common diagnostic test for dengue detection. It is a simple blood test whereby a sample of the patient’s blood is drawn from the arm and and analyzed in a laboratory.

The price of dengue test in Pakistan is Rs. 90 and it is widely available at labs across the country. You can also book a dengue test online in Pakistan through oladoc.

2. Complete Blood Count (CBC)

The CBC test counts the number of cells in a sample of your blood. Dengue fever can lead to a decreased count of white blood cells (which combat infection) and platelets (which mitigate bleeding).

A complete blood count can help inform your doctor about the potential severity of your illness.

3. Molecular Tests

These tests identify the genetic material of the virus. The nucleic acid amplification test (NAAT) first makes many copies of the virus’s RNA.

There are very low amounts of dengue virus in a blood sample, so by amplifying the genetic material, it is easier to detect the objective. One type of NAAT is polymerase chain reaction (PCR).

4. Serologic or Antibody Tests

These tests look at a sample of your blood for antibodies, which are proteins your immune system produces against viruses such as the dengue virus. The MAC-ELISA detects molecules that oppose dengue fever.

Conclusion

Dengue fever is severe but also preventable, and its rate of spread is alarming in mosquito-endemic areas. As awareness of dengue increases and intervention efforts like mosquito control and personal protective measures help reduce the risk, we can help contribute to decreasing the rates of dengue and protect communities from the threat of this serious illness.

Frequently Asked Questions (FAQs)

1. Is dengue fever contagious?

No, dengue is not contagious from person to person. It is transmitted by an Aedes mosquito that infects someone and then subsequently bites another individual.

2. What is the treatment for dengue?

To treat dengue, doctors advise plenty of rest, hydration, and adding immunity boosting food to your diet as your body fights the virus and gradually recovers.

3. Can dengue be prevented?

The dengue virus vaccine, Q-denga® (TAK-003) is recommended by WHO for children of 6 to 16 years of age for dengue prevention in high risk areas where dengue is prevalent. Other preventive measures include wearing long sleeves and wearing mosquito repellents.