Dengue Virus - Epidemiology

What is Dengue Virus?

The Dengue virus is a mosquito-borne viral infection that causes dengue fever. It is a member of the Flaviviridae family and has four distinct serotypes (DENV-1, DENV-2, DENV-3, and DENV-4). Infection with one serotype provides lifelong immunity to that specific serotype but not to the others, making multiple infections possible.

How is Dengue Virus Transmitted?

Dengue virus is primarily transmitted through the bites of infected Aedes mosquitoes, particularly Aedes aegypti and Aedes albopictus. These mosquitoes thrive in tropical and subtropical climates and are commonly found in urban and semi-urban areas.

What are the Symptoms of Dengue Fever?

Symptoms of dengue fever usually appear 4-10 days after the mosquito bite and include high fever, severe headache, pain behind the eyes, joint and muscle pain, rash, and mild bleeding (such as nose or gum bleeding). Severe dengue, also known as dengue hemorrhagic fever or dengue shock syndrome, can lead to severe bleeding, organ impairment, and death.

What is the Epidemiology of Dengue?

Dengue is endemic in over 100 countries, primarily in tropical and subtropical regions of Southeast Asia, the Western Pacific, the Americas, Africa, and the Eastern Mediterranean. The World Health Organization estimates that there are approximately 390 million dengue infections per year, with about 96 million manifesting clinically. The disease has seen a dramatic increase in incidence over the last few decades, partly due to urbanization, increased travel, and climate change.

How is Dengue Diagnosed and Treated?

Dengue diagnosis is primarily based on clinical symptoms and can be confirmed through laboratory tests such as PCR (Polymerase Chain Reaction), ELISA (Enzyme-Linked Immunosorbent Assay), and NS1 antigen detection. There is no specific antiviral treatment for dengue; management focuses on supportive care, including hydration, pain relief, and monitoring for complications. Severe cases may require hospitalization for intravenous fluids and blood transfusions.

What are the Prevention and Control Measures?

Prevention of dengue focuses on mosquito control and personal protective measures. This includes eliminating mosquito breeding sites, using insect repellent, wearing long-sleeved clothing, and using mosquito nets. Community-based programs and public health campaigns are essential in reducing mosquito populations and raising awareness. The Dengvaxia vaccine has been approved in some countries for individuals aged 9-45 years who have had a previous dengue infection.

What is the Public Health Impact of Dengue?

Dengue poses a significant public health challenge, particularly in developing countries with limited resources. The economic burden includes costs of healthcare, lost productivity, and vector control efforts. The disease also causes a considerable social impact, affecting quality of life and placing a strain on healthcare systems. Ongoing research and international collaboration are crucial in developing effective vaccines, treatments, and strategies for controlling the spread of dengue.