Final answer:
Dengue fever, caused by the dengue virus, is geographically spread predominantly in tropical regions and transmitted by Aedes mosquitoes. Flaviviruses, including dengue, Zika, and West Nile virus, can rapidly expand their range with the movement of mosquito vectors, which are influenced by climate change. Vector control is crucial to manage the spread of these diseases.
Step-by-step explanation:
Geographical Spread of Dengue and Distribution of Flaviviruses
Dengue fever is a viral disease caused by one of four serotypes of the dengue virus (DENV 1-4), which are arboviruses belonging to the Flavivirus genus. The geographic spread of dengue is primarily in tropical regions worldwide, with an estimated 50 million to 100 million infections occurring annually. Dengue viruses are transmitted to humans by Aedes aegypti or Aedes albopictus mosquitoes. As the global climate warms, diseases like dengue fever, as well as yellow fever, West Nile virus, Zika virus, and chikungunya, are expected to spread to new areas due to expanding ranges of vector mosquitoes and the acceleration of their life cycles.
The distribution of flaviviruses, which also includes the West Nile virus and Zika virus, is linked to the distribution of their arthropod vectors. These flaviviruses can expand their range rapidly over a large geographic area through the movement of their mosquito vectors, which breed and multiply more quickly in warmer climates. The most effective method for controlling outbreaks of these arboviral diseases is vector control.
Signs and symptoms of Zika virus infection in adults include fever, rash, joint pain, and conjunctivitis. Zika virus infection is considered a serious public health threat because it can cause birth defects and is associated with neurological conditions such as Guillain-Barré syndrome.
Significance of Vector Control
Vector control remains the best strategy for combating arboviral diseases, which includes eliminating breeding sites, using insect repellents, wearing protective clothing, and the strategic use of pesticides. The diagnostic approach for diseases such as dengue and chikungunya involves tests like IFA, EIA, ELISA, PCR, and RT-PCR to detect viral antigens and patient antibody responses.