Dengue Fever: How the Infection Works

Dear, Auntie:

In your last letter you asked me what happen in the body of a person with a Dengue virus infection. This is referred to as the pathophysiology of the infection, essentially how the infection takes a normal body and makes it sick.

There are about 3 billion people in the world who are at risk of getting infected with Dengue fever. Every year, the World Health Organization reports about 100 million cases of dengue fever. Of these cases about 1% go on to develop Dengue Hemorrhagic Fever (indicated by blood in the feces and vomit) or Dengue Shock Syndrome (due to dehydration). Dengue Hemorrhagic Fever and Dengue Shock Syndrome are the very concerning forms of dengue infection because they are the ones that too often result in death.[1]

Dengue virus is a small virus composed of a single-strand of genetic material. When the virus enters the body, it begins to make copies of itself (replication). It does this by attaching to the surface of the cells in our bodies, entering the cells, hijacking the cell's energy and machinery to make copies of itself, forming packets containing a large amount of dengue virus within our cells, then breaking open our cells and spreading those viral packets to nearby cells.[2]

Here is a cool video about how the virus affects humans:

References:
1. Leong AS, Wong KT, Leong TY, et al. The pathology of Dengue Hemorrhagic Fever.Semin Diagn Pathol 2007; 24(4): 227-236. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18085063
2. Rothman AL, Hirsch MS, Baron EL. Pathogenesis of dengue virus infection. UpToDate Website. Updated: March 2015. Accessed: April 2015.