Dengue & Zika

Transmission of the dengue virus is shown in three stages. In the first stage (panel a), a high-magnification photograph shows a mosquito inserting its proboscis into a region of human skin, inoculating the human with the dengue virus. In the second stage (panel b), a photomicrograph shows several skin dendritic cells that are infected with the virus. These infected dendritic cells produce interferon to help limit the spread of infection. In the third stage (panel c), a photomicrograph shows lymph nodes infected with the virus. Infection of the lymph nodes leads to viremia. Text in panel c indicates the infection can be fought with neutralizing antibodies, activation of the complement system, and cytotoxic T lymphocytes.
A diagram shows dengue virus particles binding to five pre-existing antibodies. The virus-antibody complex then binds to external receptors on monocytes. The virus particles gain access to the inside of the monocytes after binding these receptors and are then able to replicate and increase the viral load inside the infected body.
Dengue viral infections can result in a variety of symptoms. How does the body respond when it is infected with dengue? What factors put some people at a greater risk of severe dengue illnesses than other people?

Antibodies formed against Dengue from a previous infection act like Trojan horses for the current Dengue virus of a different serotype. They cannot neutralize the current infection, and instead, facilitate the entry into monocytes, where the DNA replicative mechanism gets hijacked to multiply the viruses. This phenomenon is called “Antibody-Dependent Enhancement”.

Dengue Antibody and Zika: Friend or Foe?

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Zika virus is a mosquito-borne Flavivirus related to dengue that is rapidly spreading through the Americas. This outbreak is occurring in dengue-endemic areas where the population has…

New dengue vaccine could lead to more cases, experts warn

The newly licensed dengue vaccine could lead to an increase in cases of the disease if not implemented correctly, warn experts in a new study.