How does dengue fever affect the body

When treated quickly with intravenous fluid replacement, most patients recover from severe dengue. There is currently no cure for dengue and no vaccine to prevent dengue infections. Dengue Transmission. The dengue virus is spread through a human-to-mosquito-to-human cycle of transmission, with the mosquito Aedes aegypti as the primary vector.

These mosquitoes live near humans in tropical and subtropical regions of the world. Female Aedes aegypti become dengue vectors after feeding on the blood of a person infected with the dengue virus.

Infected mosquitoes continue to transmit dengue with each blood meal for the rest of their lives. Aedes aegypti have a complex life cycle that includes aquatic and terrestrial stages. These mosquitoes lay their eggs inside containers, and new Aedes aegypti hatch when the containers are filled with water. Dengue poses the greatest risk in highly populated regions with rainy seasons where there are large populations of Aedes aegypti with a high degree of contact between the mosquitoes and humans.

Dengue Viruses. Like other viruses, the dengue virus is a microscopic structure that can only replicate inside a host organism. The dengue virus has a roughly spherical structure.

It is composed of the viral genome and capsid proteins surrounded by an envelope and a shell of proteins. After infecting a host cell, the dengue virus hijacks the host cell's machinery to replicate the viral RNA genome and viral proteins.

Newly synthesized dengue viruses can go on to infect other host cells. Host Response to the Dengue Virus. Dengue viral infections can result in a range of symptoms. Some people show no symptoms or only have mild signs of the disease. Other people develop severe complications. How does the body respond to a dengue infection? The human body's immune system is the primary defense against the dengue virus. Pain relievers with aspirin or ibuprofen should be avoided, as they can make bleeding more likely.

Most cases of dengue fever go away within a week or two and won't cause any lasting problems. If someone has severe symptoms of the disease, or if symptoms get worse in the first day or two after the fever goes away, seek immediate medical care.

This could be an indication of DHF, which is a medical emergency. To treat severe cases of dengue fever at a hospital, doctors will give intravenous IV fluids and electrolytes salts to replace those lost through vomiting or diarrhea. When started early, this is usually enough to effectively treat the disease. In more advanced cases, doctors may have to do a blood transfusion. In all cases of dengue infection, efforts should be made to keep the infected person from being bitten by mosquitoes.

This will help prevent the illness from spreading to others. There's no vaccine to prevent dengue fever. The best protection is to prevent bites by an infected mosquito. Be sure to:. By taking these precautions and keeping your kids away from areas that have a dengue fever epidemic, the risk of contracting dengue fever is small for international travelers. Reviewed by: Steven Dowshen, MD. Larger text size Large text size Regular text size. What Is Dengue Fever? What Causes Dengue Fever?

How Is Dengue Fever Diagnosed? Dengue fever usually starts with a fever, joint pain, rash and nausea. Without treatment, the virus can cause damage to blood and lymph vessels and lead to dengue hemorrhagic fever, which is marked by difficulty breathing, bruising and bleeding from the nose, gums or under the skin. Each year, the virus infects up to million people and kills about 22,, most of them children. To infect a cell, the dengue virus initially binds to the cell surface.

It gains entry into the cell when it becomes enveloped by the cell membrane during the creation of a pouch-like structure known as an endosome. The virus waits inside the endosome until it has traveled deep within the cell; then, it fuses its membrane with the endosomal membrane and forms a pore through which it releases its genetic material. Once inside the fluid interior of the cell, the virus begins to reproduce itself.

Researchers have studied viral fusion in the laboratory at the cell surface or by using artificial cell membranes. However, attempts to fuse dengue virus under either of these conditions have been unsuccessful.