meningitis, infectious

meningitis, infectious Inflammation of the meninges due to bacterial, viral, or protozoan infection. Most of the agents known to cause meningitis are infectious, but very few people exposed to them develop meningitis. Those at greatest risk for infectious meningitis include people with AIDS, infants, transplant patients, and others whose immune systems may be compromised. For this reason, infectious meningitis patients are almost always isolated until the risk of spreading the illness to others has passed.