Inclusion Criteria:  Patients with suspected meningitis : the patient has a new fever (>38.5℃), accompanied by ≥1 of the following manifestations：  Stiff neck Change in state of consciousness Other signs of meningitis: such as meningeal irritation.  Patients with suspected encephalitis: Unexplained changes in the state of consciousness for more than 24 hours (including lethargy, agitation, personality changes, etc.) or accompanied by recent memory impairment, with the following ≥1 manifestations:  Fever during the course of the disease (≥ 38℃); (oral temperature) Convulsions or focal neurological symptoms; Increase in the number of cerebrospinal fluid cells (>4*10^6/L); Abnormal EEG that meets the manifestations of encephalitis and cannot be attributed to other reasons Imaging suggests encephalitis (CT or MRI) Have not received effective anti-infective treatment yet Have an identifiable address and live in the area during treatment. Suspected encephalitis/meningitis patients who are willing to participate in trial treatment and follow-up and can give informed consent (if the subject is illiterate, sign or hearing consent is required). Willing to comply with follow-up research procedures.  Exclusion Criteria:  Known breastfeeding or pregnancy Failure to comply with treatment or follow-up time; The researcher believes that there are any conditions (social or medical) that allow subjects to participate in unsafe; Participating in other clinical studies Insufficient cerebrospinal fluid or blood samples Clinically diagnosed infections, tumors or other neurological diseases