The duration of meningitis without being aware of the infection can vary depending on the type. For viral meningitis, symptoms are typically mild and may improve within a few days, with most people recovering fully after one to four weeks. On the other hand, bacterial meningitis has a sudden onset, and symptoms can progress rapidly, leading to serious health complications or even death within a matter of hours if left untreated. Therefore, if there is a suspicion of meningitis, immediate medical attention is crucial to prevent serious consequences.