From MSNBC.COM: 

Beyond blisters: Herpes has an upside

Virus shown to protect mice against bubonic plague, other dangerous germs

The herpes family of viruses can have a surprising upside — it can protect against the bubonic plague and other bacterial contagions, at least in mice.

Research into whether a similar mechanism applies to humans and other mammalian hosts should be conducted, said viral immunologist Skip Virgin at Washington University School of Medicine in St. Louis. “There may be symbiotic advantages to chronic infections with these viruses.”

These new results do not mean people should go out and get infected with herpes, Virgin stressed. They probably already are. Nearly all humans become infected with multiple herpes virus family members during childhood. These germs not only include the herpes simplex viruses, which lead to cold sores and possibly genital herpes, but also the diseases responsible for chickenpox and “mono,” as well as several less well-known ailments. Herpes infections have bedeviled animals for more than 100 million years.

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