Lymphocytic choriomeningitis virus (LCMV)

Virology

  • Family: Arenaviridae
  • Genome: Enveloped, bi-segmented, negative-sense ssRNA
  • Reservoir: Mus musculus (house mouse)
  • Humans are incidental hosts

Transmission

  • Aerosolized rodent excreta (urine, feces, saliva)
  • Direct contact with contaminated materials
  • Rarely:
    • Solid organ transplantation (documented fatal clusters)
    • Congenital transmission
    • Pet rodents (hamsters)

Clinical PresentationBiphasic illness is classic but not universal:Phase 1 (viremic):

Phase 2 (immunologic):

  • Aseptic meningitis
  • Meningoencephalitis
  • Rarely myelitis or encephalopathy

CNS findings

Immunocompromised

  • Severe, disseminated disease
  • High mortality reported in transplant recipients

Pregnancy Considerations

  • Vertical transmission → congenital LCMV
  • Similar to TORCH infections:
    • Hydrocephalus
    • Chorioretinitis
    • Intracranial calcifications
    • Neurodevelopmental impairment

Diagnosis

  • Serology: LCMV IgM/IgG (paired titers)
  • PCR: CSF or blood (availability varies)
  • Often underdiagnosed due to nonspecific presentation

Treatment

  • No FDA-approved antiviral therapy
  • Supportive care is standard

Ribavirin

  • In vitro and animal activity
  • Limited human data (case reports/compassionate use)
  • Considered only in severe or immunocompromised cases
  • Teratogenic → contraindicated in pregnancy

Pharmacist Key Points

  • No role for empiric antivirals in routine viral meningitis unless high suspicion
  • Avoid unnecessary antibacterials once diagnosis clarified
  • Counsel transplant teams on donor-derived infection risk
  • Infection control: standard precautions; no human-to-human spread outside transplant/pregnancy contexts
  • Public health notification may be required depending on jurisdiction

Prognosis

  • Immunocompetent adults: generally good recovery
  • Mortality:
    • <1% overall
    • Up to 30–50% reported in transplant-associated cases
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