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The current analysis revealed genetic evidence of many infectious viruses found in semen. Semen provides a hiding place and breeding ground for many dangerous viruses
Zika, Ebola, Marburg, Lassa fever, Chikungunya, Mumps, Epstein-Barr and Chhicken pox are present in human semen. Non-sexually transmitted viruses can persist in semen, and this increases the risk of sexual transmission.
The presence of viruses in semen does not mean that every virus can be sexually transmitted, common viruses in semen are: hepatitis viruses, herpes viruses, and range of other viruses that can be pass from person-to-person via blood, saliva or other means.
It is easy for viruses to get in to the semen, but relatively hard for the immune system to kill the viruses, the immune system recognized sperm as foreign objects in the body and this subject sperm to attack from the immune system.
For sperm to survive, the testes are immunologic locations in the body, where the immune system does not have much access to, this immunological location can also protect dangerous viruses.
Zika is cleared from the bloodstream within one week of treatment, but can persist in semen for months, Ebola survivors can reigniting an outbreak because the virus remained latent and active in their testicles.
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