Herpes Virus is of many types that affect humans and non-humans. One such kind of virus is the Herpes B virus that predominantly found in monkeys but it also has the capability to severely affect humans. Though the Herpes B virus doesn't severely affect monkeys it is almost fatal to humans. You shall get exposure if you come into contact with the monkey's saliva or getting bitten or scratched by the Monkey.
This virus in humans causes ascending encephalitis and meningitis that often cause patient death. The good news is that contamination of the Herpes B virus in Humans is very rare. See the full report here - https://www.herpescurecare.com/herpes-b-virus-a-death-dealing-contamination/