References:
- Global Infectious Diseases and Epidemiology Online Network: Infectious Diseases of the Philippines, 2013 eBook Edition, ISBN 978-1-61755-582-4, by Stephen Berger. Accessed here.
Aseptic (Viral) Meningitis
| Agent | VIRUS - RNA. Picornaviridae, enteroviruses |
| Reservoir | Human |
| Vector | None |
| Vehicle | Fecal-oral Droplet |
| Incubation Period | Variable |
| Diagnostic Tests | Viral isolation (stool, CSF, throat) Serology |
| Typical Adult Therapy | Supportive |
| Typical Pediatric Therapy | As for adult |
| Clinical Hints | Lymphocytic meningitis (normal CSF glucose); often follows sore throat; typically occurs during late summer and early autumn in temperate regions. |
| Synonyms | Aseptic meningitis, Encephalitis - viral, Meningite virale, Meningitis, viral, Meningo-encefalite virale, Viral encephalitis, Viral meningitis. |
WHO Case Definition for Surveillance
Clinical case definition: a case with fever 38.5°C and one or more of the following:
- neck stiffness
- severe unexplained headache
- neck pain and 2 or more of the following: photophobia, nausea, vomiting, abdominal pain, pharyngitis with exudates
For children <2 years of age a case is defined as
- A case with fever 38.5°C and one or more of the following: irritability, bulging fontanelle
Laboratory criteria for confirmation: the specific virus confirmed on cell culture.
Case classification
- Suspected: A case that meets the clinical case definition and one or more of the following:
- normal CSF glucose and normal or mild increase in CSF protein (>50 mg/dl), moderate increase CSF cells (<500/mm3) and lymphocyte predominance (>50%)
- CSF Positive for viral genomic sequences using PCR (Polymerase Chain Reaction)
- Epidemiological link to a confirmed case
- Confirmed: A suspected or probable case with laboratory confirmation.
As a group, the viral meningitides are characterized by fever, headache, meningismus and lymphocytic pleocytosis.
- Major complications and sequelae are unusual.
- The cerebrospinal fluid glucose level is normal, and a transitory neutrophilic pleocytosis is occasionally encountered.
- CSF pleocytosis is often absent among children with enteroviral meningitis.
Bacterial Meningitis
| Agent | BACTERIUM. Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae, et al. |
| Reservoir | Human |
| Vector | None |
| Vehicle | Air Infected secretions |
| Incubation Period | Variable |
| Diagnostic Tests | CSF microscopy and culture Blood culture Note: Antigen detection is non-specific and rarely useful. |
| Typical Adult Therapy | Bactericidal agent(s) appropriate to known or suspected pathogen + dexamethasone |
| Typical Pediatric Therapy | As for adult |
| Vaccines | H. influenzae (HbOC-DTP or -DTaP) Haemophilus influenzae (HbOC) Haemophilus influenzae (PRP-D) Haemophilus influenzae (PRP-OMP) Haemophilus influenzae (PRP-T) Meningococcal Hepatitis B + Haemoph. influenzae |
| Clinical Hints | Headache, stiff neck, obtundation, high fever and leukocytosis; macular or petechial rash and preceding sore throat suggest meningococcal infection |
| Synonyms | Bacterial meningitis, Enfermedad Meningococica, Haemophilus influenzae, Haemophilus influenzaes, HIB meningitis, HIBs, Infections a meningocoque, Meningite batterica, Meningite meningococcica, Meningococcal, Meningokokken Erkr., Meningokokkose |
WHO Case Definition for Surveillance: Meningococcal Infection
Clinical case definition: an illness with sudden onset of fever (>38.5°C rectal or >38.0°C axillary) and one or more of the following:
- Neck stiffness
- Altered consciousness
- Other meningeal sign or petechial or purpuric rash
- In patients <1 year, suspect meningitis when fever accompanied by bulging fontanelle.
Laboratory criteria for diagnosis
- Positive CSF antigen detection or
- Positive culture
Case classification
- Suspected: A case that meets the clinical case definition.
- Probable: A suspected case as defined above and turbid CSF (with or without positive Gram stain) or ongoing epidemic and epidemiological link to a confirmed case
- Confirmed: A suspected or probable case with laboratory confirmation.
WHO Case Definition for Surveillance: Haemophilus influenzae type B (Hib) disease
Clinical description: Bacterial meningitis is characterized by fever of acute onset, headache and stiff neck. Meningitis is not a specific sign for Hib disease, and Hib disease cannot be diagnosed on clinical grounds.
Laboratory criteria for diagnosis
- Culture: isolation of Hib from a normally sterile clinical specimen, such as cerebrospinal fluid (CSF) or blood.
- Culture of Hib from non-sterile sites such as the throat, where bacteria can grow without causing disease, does not define Hib disease.
- Antigen detection: identification of Hib antigen in normally sterile fluids, by methods such as latex agglutination or counter-immunoelectrophoresis (CIE).
Case classification
- Potential: (bacterial meningitis case): a child with a clinical syndrome consistent with bacterial meningitis.
- Probable: Not applicable.
- Confirmed: A case that is laboratory-confirmed (growth or identification of Hib in CSF or blood).
- Note: Any person with Hib isolated from CSF or blood may be reported as a confirmed case, regardless of whether their clinical syndrome was meningitis.
As a group, the bacterial meningitides are characterized by signs of sepsis, fever, headache, meningismus and neutrophilic pleocytosis.
- 33% to 69% of patients with meningococcal infection have hyperglycemia on admission
- 7.5% of patients with meningococcal infection present with arthritis.
- Major complications and sequelae are common.
- Delayed cerebral thrombosis is encountered in 1.1% of cases.