Section 15 Epidemic Cerebrospinal Meningitis

Introduction of Epidemic Cerebrospinal Meningitis

Epidemic cerebrospinal meningitis is an acute respiratory infectious disease caused by meningococcus.

Human being is the host to meningococcus，and human exclusively infected and diseased. Carriers and patients are infection source of this disease. Meningococcus is transmitted via droplets. All populations are susceptible to this disease such as the other respiratory infectious diseases.

The disease may become epidemic in winter and spring，and taking on sporadic，outbreak and great epidemic forms. Morbidity in children is high. Before 1970s this disease is rampant having a high morbidity and mortality. Until in the 1980s when some comprehensive preventive measures were implemented based on the polysaccharides vaccine，and nowadays this disease takes place in a sporadic form.

1. Diagnostic criteria

（1）Epidemiological history：

local outbreak of epidemic cerebrospinal meningitis or history of close-contact to patients with epidemic cerebrospinal meningitis.

（2）Clinical manifestations：

sudden high fever，headache，vomiting，petechia or ecchymosis in skin mucous membrane，conscious disturbance，and positive signs of meningeal irritation.

（3）Laboratory data

1）Blood routine test：

total number of white blood cell up to （15-30）×10⁹/L，and neutrophil up to>80% accompanied by toxic granules and vesicles，in more severe cases leukemoid reaction may occur.

2）Cerebrospinal fluid examination：

pressure of the fluid may increase in early stage however appearance may be normal. The fluid becomes blurred or purulent in later，with cell count up to more than 1×10⁹/L and neutrophilesare predominant. Protein content in the fluid dramatically increases and sugar content significantly decreases. Chloride content sags. In patients with sepsis changes in cerebrospinal fluid are not significant.

3）Bacterial examination：

positive findings of negative gram-stain diplococcus on smear of deposit of cerebrospinal fluid or skin petechia is diagnostically valuable. Positive isolation and culture of meningococcus from cerebrospinal fluid or blood contribute to confirmed diagnosis.

4）Immunological test：

ELISA or RIA is used to detect specific polysaccharides antigen of meningococcus in cerebrospinal fluid or blood or urine. 4 folds or greater increase in specific antibody titer between acute-phase and convalescent –phase sera is auxiliarily valuable for diagnosis.

2. Major measures dealing with the measles epidemic

（1）Suspected patients and patients：

early discovery，early diagnosis，early reporting，early isolation，and early treatment. Antibiotics such as sulfonamide and penicillin G should be sufficiently administered to patients.

（2）Cutting off transmission routes：

conducting disinfection by exposure to sunlight，phenol or lysol. Clean ward using wet cleaning and ventilation，and final disinfection is needed.

（3）Protection of susceptible populations：

taking personal protection measures such as wearing masks，distancing from measles patients and receiving emergency immunization.

流行性脑脊髓膜炎流行病学个案调查表

Epidemiological Questionnaire for Cases of Epidemic Cerebrospinal Meningitis

Questionnaire

（本节编者-马钰　本节核对-吴迪）