Introduction

Dengue is a viral fever which is transmitted by the bite of mosquitoes. Those mosquito species are “Aedes egypti” and “Aedes albopictus”. These mosquitoes most commonly bite humans in the mornings and evenings. These mosquitoes breed in clean still water.

Dengue virus has four serotypes. Simply there are four different types. So one can get infected by dengue several times. Because our body generates immunity to one serotype of dengue. If one person is infected again with the same previous serotype, our body’s immune system will detect, fight against it, and destroy it. That means the human body has lifelong immunity to particular serotypes of dengue virus after the infection. 

But if you get infected again with another serotype, even if your immune system identifies the threat it can not effectively fight against the new serotype type because it’s not the same as the previous one. Due to this your immune system will work in a way that will worsen the condition. That’s why the disease gets more serious when you get infected for the second or third time.

Epidemiology

Dengue fever is endemic in Southeast Asia, Southern China, Africa, Taiwan, the Pacific islands, and the Caribbean. Dengue is periodically epidemic in some countries, especially in rainy seasons.

Pathophysiology

Actually, in dengue fever, the virus will attack the platelets and vessel walls. that is a complex immune reaction. simply results will increase the capillary permeability and reduce the blood clotting mechanism. this will increase the extravasation of the fluid from the vessels. due to reduce coagulability internal bleeding can happen. due to inadequate volume of the blood inside the vessels leads to intravascular coagulation of the red blood cells.

Symptoms

The most common symptoms are headache, pain around the eyes, (actually, it is retro-orbital pain, which means pain originates behind the eyeball) nausea, vomiting, muscle pain, and joint pain. Also, there can be red eyes and abdominal pain. Symptoms usually will last for two to seven days. Usually, patients will recover after a week. But bed rest is needed for two to three weeks more.

Signs

Right hypochondriac tenderness, petechiae (rash). Warning signs are severe vomiting, vomiting of blood, gum bleeding, blood in stool, and being restless or irritable.

Complications

• Dengue hemorrhagic fever 
• Carditis
• Dengue encephalopathy 
• Hypocalcaemia 
• Hypoglycemia

Investigations

A full blood count will show dropping white blood cell counts and platelet counts. White blood cell count will start to drop before the platelet count in the initial stages of the disease. In the recovery period, both white blood cell and platelet count will rise. Interestingly here also the white blood cell count will start to rise before the platelet rises. In a normal healthy adult, the platelet count will vary from 150000 to 450000. 

Another blood test is the NS1 antigen test. This test identifies dengue infection by detecting the Dengue antigen. Dengue antibody tests are also helpful to diagnose dengue. 

An ultrasound scan of the abdomen and thorax will show if there is any fluid leakage due to dengue infection.

Management

Meet your doctor and take advice.

A patient with dengue should have adequate bed rest. If you suspect to have dengue fever take only paracetamol to alleviate the fever, Do not take NSAIDs like aspirin as it can worsen complications like gastric bleeding. Measure your fluid intake and urine output and record it so your doctor can get an idea about your condition. Take fluids like kanji and king coconut. Do not take colored drinks as they can mislead the identifying passing blood with urine. 

Admit to the hospital if your doctor advises you to do so. Usually, if the platelet count is less than 100,000, a significant drop even above the range, complications such as leaking or bleeding, other co-morbidities, and social reasons are considered before hospital admission. admission criteria differ around the world because of the limitations in available facilities.

Prevention

The most important thing is to destroy the breeding sites of dengue mosquitoes. Identify the places around your house that can collect water and destroy them as the mosquitoes lay eggs mostly in clean still water. And do the fogging in the dengue endemic areas. Use mosquito nets and mosquito repellents. There’s a dengue vaccine also.

Summary

Dengue fever is a viral disease transmitted by Aedes mosquitoes, primarily in Southeast Asia, Southern China, Africa, and other regions. The virus has four serotypes, and immunity to one serotype does not protect against the others. Dengue infection can lead to capillary permeability, reduced blood clotting, and internal bleeding. Common symptoms include headache, eye pain, nausea, vomiting, and joint pain, with recovery usually taking a week or more. Severe cases can result in complications such as dengue hemorrhagic fever and cardiac issues. Diagnosis involves blood tests, including the NS1 antigen test, while ultrasound scans can reveal fluid leakage. Management includes bed rest, paracetamol for fever, and close monitoring of platelet counts. Hospital admission is considered based on platelet count, complications, and other factors. Prevention focuses on eliminating mosquito breeding sites, using mosquito nets and repellents, and considering vaccination.

Conclusion

Dengue fever is a significant public health concern in various parts of the world, especially in regions with a tropical climate. Understanding its transmission, the importance of mosquito control, and the potential for severe complications underscores the need for proactive prevention measures. While there is no specific antiviral treatment for dengue, timely diagnosis and appropriate medical care can greatly improve patient outcomes. With ongoing research and the availability of a dengue vaccine, efforts to combat this disease continue to progress, offering hope for reducing its impact on affected communities. Education and awareness are essential in the fight against dengue, emphasizing the importance of community involvement and public health initiatives to control the spread of the virus.

FAQs

1. What is dengue fever?

• Dengue fever is a viral illness caused by the dengue virus, which is transmitted to humans through the bites of infected Aedes mosquitoes, primarily Aedes aegypti and Aedes albopictus.

2. What are the common symptoms of dengue fever?

• Common symptoms include high fever, severe headache, joint and muscle pain, rash, and bleeding. Some people may experience mild symptoms, while others can develop severe dengue, also known as dengue hemorrhagic fever or dengue shock syndrome.

3. How is dengue fever diagnosed?

• Diagnosis is typically made through a blood test that checks for the presence of the dengue virus or antibodies to the virus. Healthcare professionals may also consider a person’s symptoms and medical history.

4. Is there a specific treatment for dengue fever?

• There is no specific antiviral treatment for dengue fever. Treatment primarily involves supportive care, including rest, hydration, and pain relief. Severe cases may require hospitalization and close monitoring.

5. Can dengue fever be prevented?

• Yes, dengue fever can be prevented. Prevention measures include using mosquito repellent, wearing long-sleeved clothing, and using bed nets, especially during peak mosquito activity times. Eliminating mosquito breeding sites, such as stagnant water, is also essential.

6. Is dengue fever contagious from person to person?

• Dengue fever is not directly contagious from person to person. It is transmitted exclusively through the bites of infected mosquitoes. However, an infected person can serve as a source of the virus for mosquitoes that bite them.

7. Can you get dengue fever more than once?

• Yes, it is possible to get dengue fever multiple times. There are four different serotypes of the dengue virus, and infection with one serotype does not provide immunity against the others. In fact, subsequent infections with different serotypes can increase the risk of severe dengue.

8. What are the warning signs of severe dengue?

• Warning signs of severe dengue include severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums, fatigue, restlessness, and a significant drop in platelet count. If any of these symptoms occur, it’s essential to seek medical attention immediately.

9. Where is dengue fever most commonly found?

• Dengue fever is prevalent in tropical and subtropical regions of the world, particularly in parts of Asia, the Pacific Islands, the Americas, and Africa. Travelers to these areas should take precautions to avoid mosquito bites.

10. What is the current status of dengue vaccines?

• As of my last knowledge update in September 2021, there are dengue vaccines available in some countries. These vaccines have varying levels of effectiveness and are recommended for specific populations, such as individuals who have had a prior dengue infection. Vaccine availability and recommendations may vary by region, so it’s important to consult with healthcare professionals for the latest information.