The incubation period of meningitis can be long or short, depending on the type of meningitis pathogenic microorganism and the virulence of the pathogenic microorganism. Usually viral infections cause viral meningitis with an incubation period of less than 2 weeks, while some other bacterial meningitis, such as Mycobacterium tuberculosis, usually cause a slightly longer incubation period, with 2 weeks, 2 months, or even 6 months possible. There is another category of pathogenic microorganisms, such as herpes simplex virus, which can be latent in human ganglia for a long time, usually without symptoms, and once the patient’s resistance decreases or the virus multiplies and returns from latent state to productive state, clinical symptoms of meningitis will appear, so the latency period can be long or short, or even lifelong latency. When the pathogenic microorganism is latent in the body for a long time, there may be no clinical symptoms, but if the patient once dizziness, headache, especially headache, nausea, vomiting and blurred vision, it may suggest a recurrence of infection, at which time it is recommended to go to the hospital for further consultation and treatment to clarify the presence of acute intracranial infection.