Dengue virus

Definition

Dengue virus is an arthropod-borne virus (arbovirus) that causes dengue fever, a tropical disease characterized by high fever, severe headaches, pain behind the eyes, joint and muscle pain, rash, and mild bleeding. This virus is classified within the Flaviviridae family and is primarily transmitted through the bites of infected Aedes mosquitoes, particularly Aedes aegypti.

5 Must Know Facts For Your Next Test

1. Dengue virus has four distinct serotypes (DENV-1, DENV-2, DENV-3, DENV-4), which can cause varying degrees of disease severity.
2. Secondary infections with a different serotype can increase the risk of developing severe dengue hemorrhagic fever due to antibody-dependent enhancement.
3. The global incidence of dengue has risen dramatically in recent decades, with an estimated 390 million infections per year worldwide.
4. Dengue virus can persist in the human body for extended periods, leading to chronic symptoms and potential long-term health issues.
5. Preventive measures against dengue primarily focus on controlling mosquito populations and reducing exposure to mosquito bites through personal protective measures.

Review Questions

• What are the implications of having multiple serotypes of dengue virus for public health strategies?
  • The presence of four distinct serotypes of dengue virus complicates public health strategies because immunity to one serotype does not confer protection against the others. This can lead to increased risk of severe disease upon subsequent infections with different serotypes due to antibody-dependent enhancement. Therefore, vaccination efforts and public health initiatives must take into account the need for broad-spectrum immunity and effective vector control to prevent outbreaks.
• Discuss how environmental factors contribute to the transmission dynamics of dengue virus.
  • Environmental factors such as climate change, urbanization, and rainfall patterns significantly influence the transmission dynamics of dengue virus. Warmer temperatures can expand the habitat range of Aedes mosquitoes, while heavy rainfall creates ideal breeding conditions for these vectors. Additionally, urbanization often leads to increased human-mosquito interactions due to crowded living conditions and inadequate waste management. These factors collectively elevate the risk of dengue outbreaks in affected regions.
• Evaluate the effectiveness of current vaccines in preventing dengue virus infection and their potential impact on global health.
  • Current vaccines for dengue virus, such as Dengvaxia, show varying effectiveness depending on prior exposure to the virus. While it is effective in individuals with a previous dengue infection, it poses risks for those without prior exposure. Evaluating these vaccines' impact on global health reveals a dual challenge: they can potentially reduce disease burden in endemic areas but may also inadvertently increase severe cases among unexposed populations. Ongoing research into new vaccine candidates aims to create safer options that provide broad protection against all four serotypes.

Related terms

Aedes mosquito: A genus of mosquitoes known for transmitting several viral diseases, including dengue fever, chikungunya, and Zika virus.

Flavivirus: A genus of viruses within the family Flaviviridae, known to cause various diseases in humans and animals, including dengue fever, West Nile virus, and yellow fever.

Dengue hemorrhagic fever: A severe form of dengue fever that can lead to bleeding, organ impairment, and potentially death if not properly managed.