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Japanese Encephalitis Medication

  • Author: Antonette B Climaco, MD; Chief Editor: Burke A Cunha, MD  more...
Updated: May 07, 2016

Medication Summary

No effective antiviral exists.

As stated above, mannitol is used to decrease intracranial pressure, when needed.

There are 4 classes of Japanese encephalitis vaccines. Ixiaro is the Japanese encephalitis vaccine available in the United States.


Osmotic Diuretics

Class Summary

Mannitol is recommended by some experts to help reduce intracranial pressure. Mannitol induces diuresis, which increases serum osmotic concentration. In the brain, this causes water to flow from brain cells into vascular space, thereby decreasing intracranial pressure.

Mannitol (Osmitrol)


Mannitol may be used to decrease intracranial pressure. It may reduce subarachnoid space pressure by creating an osmotic gradient between CSF in the arachnoid space and plasma. This agent is not for long-term use.



Class Summary

Induction of the antibody response to vaccine provides the capability to neutralize live Japanese encephalitis virus (JEV).[38]

Japanese encephalitis virus vaccine (Ixiaro)


Ixiaro is an inactivated vaccine prepared by propagating Japanese encephalitis virus strain SA14-14-2 in Vero cells. It is available in prefilled, single-dose syringes without preservatives or thimerosal. Antibody response is measured with a 50% plaque-reduction neutralization antibody test; a threshold of 1:10 or higher is considered protective immunity.

It is the only currently available Japanese encephalitis vaccine in the United States.

Contributor Information and Disclosures

Antonette B Climaco, MD Attending Physician, Division of Infectious Diseases, Department of Medicine, Albert Einstein Medical Center

Antonette B Climaco, MD is a member of the following medical societies: Infectious Diseases Society of America, Philippine Medical Association, HIV Medicine Association, American Academy of HIV Medicine

Disclosure: Nothing to disclose.


Katherine Talcott Melhado, DO Resident Physician, Department of Internal Medicine, Einstein Medical Center

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

Burke A Cunha, MD Professor of Medicine, State University of New York School of Medicine at Stony Brook; Chief, Infectious Disease Division, Winthrop-University Hospital

Burke A Cunha, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Additional Contributors

Asim A Jani, MD, MPH, FACP Clinician-Educator and Epidemiologist, Consultant and Senior Physician, Florida Department of Health; Diplomate, Infectious Diseases, Internal Medicine and Preventive Medicine

Asim A Jani, MD, MPH, FACP is a member of the following medical societies: American Association of Public Health Physicians, American College of Physicians, American College of Preventive Medicine, American Medical Association, American Public Health Association, Infectious Diseases Society of America

Disclosure: Nothing to disclose.


Joseph F John Jr, MD, FACP, FIDSA, FSHEA Clinical Professor of Medicine, Molecular Genetics and Microbiology, Medical University of South Carolina College of Medicine; Associate Chief of Staff for Education, Ralph H Johnson Veterans Affairs Medical Center

Disclosure: Nothing to disclose.

Alexander J Kallen, MD Instructor of Medicine, Department of Internal Medicine, Division of Outcomes Research, Dartmouth Medical School, Veterans Affairs Medical Center of White River Junction, VT

Alexander J Kallen, MD is a member of the following medical societies: American College of Physicians, American Medical Association, American Society for Microbiology, California Medical Association, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Klaus-Dieter Lessnau, MD, FCCP Clinical Associate Professor of Medicine, New York University School of Medicine; Medical Director, Pulmonary Physiology Laboratory; Director of Research in Pulmonary Medicine, Department of Medicine, Section of Pulmonary Medicine, Lenox Hill Hospital

Klaus-Dieter Lessnau, MD, FCCP is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, American Medical Association, American Thoracic Society, and Society of Critical Care Medicine

Disclosure: Sepracor None None

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

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Japanese Encephalitis Virus Geographic Distribution. Photo Courtesy of CDC.
Japanese encephalitis, 2006. Courtesy of the WHO.
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