Dengue Virus

Dengue Virus

General Context

Dengue Fever is a disease that affects people of all ages. It is a viral infection that is transmitted by the bite of a mosquito. To avoid the breeding grounds of these mosquitoes, cover containers with water, eliminate accumulated garbage in yards and open-air areas, eliminate tires or storage in closed places.

Use repellents on uncovered areas of the body and avoid tropical areas.

The best way to help your body after an infection is to stay hydrated, analgesics, monitor your body and, if necessary, visit the doctor.

Hilda Aguirre

Chem 103

September 26, 2024.

Dengue is a viral disease usually transmitted by Aedes aegypti mosquitoes

Origin:

Although it is now found in almost every country in Latin America, this small insect is not native. It arrived centuries ago from other continents, such as Africa and Southeast Asia, and is thought to have originated in primates and nonhumans. Dengue in the Americas has an endemic pattern, with outbreaks every 3 to 5 years.

History.

Dengue fever:

The oldest record dates back to China's Jin Dynasty (265 to 420 AD). In America, it became known at the end of the 18th century and became a global problem in the 20th century. Every year, 390 million dengue infections occur. The famous Cuban doctor, Carlos Juan Finlay, was the one who discovered this mosquito as a transmitter of diseases, including yellow fever, based on research he presented at the International Health Conference in 1881 in Washington, United States. It was the first time someone raised the idea of ​​a biological vector like the mosquito.

Biology:

Dengue is a viral disease transmitted by the bite of infected mosquitoes. The virus is an arbovirus of the family Flaviviridae, characterized by:

Being spherical

Having a lipid envelope 40-60 nm in diameter

Having an isometric nucleocapsid 25-30 nm in diameter-

Having a single-stranded RNA genome and positive polarity.

There are four types of dengue virus (DEN-1 to DEN-4), but infection with one does not confer immunity to the others. Therefore, subsequent episodes of disease may be more severe. Transmission of the virus from infected humans to mosquitoes depends on the viral load in the blood taken up by the mosquitoes. The main vectors of the disease are female mosquitoes of the species Aedes aegypti and Aedes albopictus.

Life Cycle: Larvae hatch from mosquito eggs and live in water. Larvae develop into pupae. Pupae develop into adult mosquitoes that can fly. Adult female mosquitoes bite humans and animals.

How affect Society:

Transmission of the virus from infected humans to mosquitoes depends on the viral load in the mosquitoes’ blood. The main vectors of the disease are female mosquitoes of the species Aedes aegypti and Aedes albopictus. Dengue virus transmission generally follows two patterns: epidemic dengue and hyperendemic Dengue. Epidemic dengue occurs when a single strain of dengue virus (DENV) is responsible for introduction and transmission. Hyperendemicity is the co-circulation of multiple DENV serotypes in a community, associated with periodic outbreaks. In hyperendemic areas, children are more affected than adults, and dengue hemorrhagic fever is relatively higher.

One model-based estimate suggests that 390 million dengue virus infections occur annually, of which 96 million are clinically manifest (2). Another study on the prevalence of dengue estimated that 3.9 billion people are at risk of dengue virus infection.

Chemistry:

Dengue virus structure: The dengue virus is a spherical structure made up of a viral genome, capsid proteins, and an envelope. Dengue virus replication after infecting a host cell, the dengue virus uses the host cell's machinery to replicate its RNA and protein

Mosquito attraction: A combination of carbon dioxide, lactic acid, and 2-ketoglutaric acid in human skin attracts female Aedes aegypti mosquitoes, which can spread dengue and other viruses. Mosquito immune cells Hemocytes, the immune cells in mosquitoes, play a key role in the spread of dengue virus. Infected hemocytes can transport the virus to the mosquito's ovaries and salivary glands, and can infect other mosquitoes

Dengue virus, a member of the Flaviviridae family, is a 50-nm virion consisting of 3 structural and 7 non-structural proteins, a lipid envelope, and a single-stranded, positive-polarity RNA of 10.7 kb. Infections are asymptomatic in up to 75% of individuals. The spectrum of disease ranges from self-limiting dengue to severe hemorrhage and shock. A fraction of infections, between 0.5% and 5%, progress to severe dengue.

Incubation period and symptoms

The typical incubation period of the disease is 4 to 7 days, and symptoms last 3 to 10 days. The consequences of a mosquito bite that injects dengue virus into the skin are not yet clear. It is not proven, but it is believed that these infected cells migrate to the lymph nodes and spread through the lymphatic system to other organs. Viremia, or the presence of the virus in the bloodstream, can occur 24 to 48 hours before the onset of symptoms.

Symptoms:

• The clinical spectrum of this disease varies from a febrile is classic dengue.
• Dengue hemorrhagic fever (DHF) or dengue shock syndrome.
• Intermittent biphasic fever,
• Chills, Headache, Myalgias, Arthralgias,
• Retro-orbital pain,
• Papular-maculus rash on the trunk and extremities,
• Nausea and /or vomiting.
• Physical examination of the patient may show moderate hepatomegaly, bradycardia, and lymphadenopathy.

The presentation of dengue, whether asymptomatic, typical, or severe, is influenced by a complex interaction of host and viral factors. Severe dengue, characterized by increased microvascular permeability and shock syndrome, is usually associated with infection by a second dengue virus serotype and the patient's immune response. I believe this to be my case because according to my blood tests, severe symptoms occurred after a second infection.

Dengue Treatment

Treatment of severe dengue: Severe dengue is a medical emergency that should be treated immediately in a hospital.

Treatment may include oxygen, intravenous fluids, blood pressure monitoring, and blood transfusions.

There is no specific treatment for dengue:

• Rest: It is important to rest as much as possible.
• Hydration: Drink plenty of fluids to avoid dehydration.
• Pain relievers: Take acetaminophen (paracetamol) to control fever and relieve pain.

Note: Avoid ibuprofen, aspirin, and other aspirin-containing medicines as they may increase the risk of bleeding.

Observe: If the patient is bleeding, it is important to monitor the patient for warning signs such as increased bleeding or a drop in blood pressure.

Treat dehydration: If there are signs of dehydration, intravenous fluids may be given.

Patients may recover spontaneously or after treatment with fluids and electrolytes.

What can or has been done to stop its spread?

Reduce your risk of getting dengue fever by protecting yourself from mosquito bites by wearing:

Clothing that covers as much of the body as possible;

Mosquito nets:

Mosquito repellents.

Mosquito breeding can be prevented:

Prevent mosquitoes from accessing egg-laying habitats through environmental management and modification.

Avoid storing stagnant water.

Cover, empty, and clean household water containers weekly.

Apply appropriate insecticides to outdoor water storage containers.

To date, a dengue vaccine has been approved for use in children 9 to 16 years of age who have had a laboratory-confirmed dengue virus infection and who live in dengue-endemic areas. Endemic areas include some U.S. territories and freely associated states.

I don't have much information, but I have learned that they have done experiments with mosquitoes that they have infected with a bacterium to reduce and spread the infection.

How to identify Dengue Mosquito?

Source Website:

https://www.biologydiscussion.com/human-diseases/diseases-caused-by-mosquitoes-biology/85092.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516305/.

https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue.