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Last reviewed: 16 Mar 2025
Last updated: 14 Jan 2025

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • history of mosquito bites
  • fever
  • arthralgias/arthritis
  • rash and other dermatological manifestations

Other diagnostic factors

  • comorbid illness
  • back pain
  • neuropathic-type pain
  • headache
  • lymphadenopathy
  • ocular manifestations
  • photophobia
  • sore throat
  • gastrointestinal manifestations
  • neurological manifestations
  • haemorrhagic manifestations

Risk factors

  • Aedes mosquito bites
  • travel to/residence in endemic area
  • outdoor exposure
  • environmental factors favouring breeding of mosquitoes
  • neonate with infected mother
  • low educational level
  • age >40 years
  • male sex
  • blood transfusion
  • blood group O positive
  • comorbid illnesses (risk of more severe disease)
  • neonate (risk of more severe disease)

Diagnostic investigations

1st investigations to order

  • FBC with differential
  • LFTs
  • erythrocyte sedimentation rate
  • CRP
  • basic metabolic panel
  • serology
  • molecular testing

Investigations to consider

  • musculoskeletal imaging
  • MRI brain
  • cerebrospinal fluid analysis
  • electromyogram
  • nerve conduction studies
  • electroencephalogram
  • placental histology

Emerging tests

  • viral culture or mice inoculation

Treatment algorithm

Contributors

Authors

Miguel G. Madariaga, MD, MSc, FACP
Miguel G. Madariaga

Infectious Diseases Consultant

Naples Community Hospital

Naples

FL

Disclosures

MGM declares that he has no competing interests.

Peer reviewers

Jessica Fairley, MD

Assistant Professor of Medicine

Division of Infectious Diseases

Emory University

Atlanta

GA

Disclosures

JF declares that she has no competing interests.

Mala Chhabra, MBBS, MD

Joint Director

National Centre for Disease Control

Delhi

India

Disclosures

MC declares that she has no competing interests.

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