Meet Dengue virus!
Dengue virus (flaviviridae family) is a small (50nm), spherical, enveloped virus carrying an RNA genome (11kb).
While the particle is spherical (because it is enveloped), the placement of the E proteins throughout the membrane give it an icosahedral-like symmetry. Each surface face is made up of a trio of E-protein dimers. These dimers are used to bind to cell receptors to initiate viral entry. The M proteins, also within the membrane, stabilize the E protein dimers. Finally, within the envelope the C protein forms a nucleocapsid around the RNA genome.
Dengue virus, structurally nearly identical to Zika virus (illustrated previously), is the cause of dengue fever. As the virus is a mosquito-born (Aedes genus) human pathogen, it is particularly present in the tropical countries of the globe.
Dengue fever typically presents within 3-14 days after infection with fever, headache, vomiting, muscle and joint pain, and a characteristic skin rash. In a very small proportion of cases the disease develops into a more severe hemorrhagic form which results in bleeding.
As of this year there is one commercially available Dengue vaccine known as Dengvaxia. It was approved by the EU in 2018 and the US in 2019. It is only approved for individuals who are between 9 and 16 years of age, have previously contracted Dengue, and live in an area that is high risk for infection.
*Because Zika and Dengue are structurally nearly identical I chose to focus entirely on the outer surface for Dengue. Reference the Zika illustration in this series to see what the inside of the capsid looks like!
Posted on Instagram on May 19, 2021.