Diagnosis and Management of Prolonged Fever and Acute Flaccid Paralysis in a 4-Year-Old Child

Etiology and Epidemiology

The American College of Physicians and the Centers for Disease Control and Prevention recommend considering Japanese encephalitis as a priority diagnosis in cases of prolonged fever and acute flaccid paralysis, especially in patients with a history of travel to rural areas in Asia or the Western Pacific, with a mortality rate of 20-30% and 30-50% of survivors presenting with neurological or psychiatric sequelae 1
The World Health Organization notes that Japanese encephalitis virus infection is associated with acute flaccid paralysis, with clinical and pathological characteristics similar to poliomyelitis, and a transmission period of 5-15 days, mainly in rural agricultural areas 2
The Centers for Disease Control and Prevention state that the transmission of Japanese encephalitis virus occurs primarily in rural areas, frequently associated with rice production and flood irrigation, and that the virus should be suspected in any patient with evidence of neurological infection who has recently returned from a country in Asia or the Western Pacific where the disease is endemic 2
The Infectious Diseases Society of America recommends suspecting Japanese encephalitis in patients with neurological infection, such as encephalitis, meningitis, or acute flaccid paralysis, who have recently returned from an endemic country in Asia or the Western Pacific 1

The American Academy of Pediatrics recommends performing three thick blood films over 72 hours to exclude malaria with confidence, even if the visited area is not typically endemic 6
The Centers for Disease Control and Prevention suggest obtaining a lumbar puncture for cerebrospinal fluid analysis, looking for lymphocytic pleocytosis with moderately elevated protein, and requesting specific serology for Japanese encephalitis virus in cerebrospinal fluid or serum 2
The World Health Organization recommends performing a brain and spinal cord magnetic resonance imaging to look for changes in the thalamus, basal ganglia, mesencephalon, pons, and medulla, as well as abnormalities of the gray matter of the spinal cord 2

The Infectious Diseases Society of America states that there is no specific antiviral therapy or medication to mitigate the effects of Japanese encephalitis virus infection, and that corticosteroids, interferon alfa-2a, or ribavirin did not improve clinical outcome in controlled trials 1
The American College of Physicians recommends careful monitoring of respiratory and bulbar function, as generalized weakness frequently affects these functions 1
The Centers for Disease Control and Prevention suggest initiating doxycycline 2.2 mg/kg of body weight twice a day immediately if scrub typhus is suspected, without waiting for laboratory confirmation, and continuing treatment for at least 3 days after fever subsides, with a minimum course of 5-7 days 3