Overview
Kyasanur forest disease (KFD), sometimes called 'monkey fever,' is a rare viral illness caused by the Kyasanur forest disease virus (KFDV), a member of the flavivirus family. It is spread to humans primarily through the bite of infected hard ticks (mainly Haemaphysalis spinigera), though contact with blood or tissues of infected animals, especially sick or dead monkeys, can also transmit the virus. The disease typically begins suddenly with high fever, severe headache, body aches, and muscle pain. Within the first few days, patients may experience bleeding from the gums, nose, or gastrointestinal tract. Some people develop abnormally low blood platelet and red blood cell counts, leading to a tendency to bleed easily. After a brief period of improvement around the second week, some patients experience a second wave of symptoms involving brain and nervous system inflammation (encephalitis), which can cause confusion, tremors, vision problems, and in severe cases, coma. There is no specific antiviral treatment for KFD. Care is supportive, focusing on managing dehydration, bleeding, and other complications. A formalin-inactivated vaccine has been developed and is used in endemic areas of India, though its effectiveness is considered moderate. Early recognition and prompt supportive care are critical to improving outcomes. The overall fatality rate is estimated at 3 to 5 percent.
Also known as:
Key symptoms:
Sudden high feverSevere headacheMuscle and body achesBleeding from gums or noseBlood in vomit or stoolLow blood platelet count causing easy bruisingNausea and vomitingDiarrheaExtreme fatigue and weaknessRed or bloodshot eyesLow blood pressureConfusion or mental changesTremors or shakingVision problemsSwollen lymph nodes
Sporadic
Usually appears on its own, not inherited from a parent
Variable
Can begin at different ages, from infancy through adulthood
FDA & Trial Timeline
3 eventsCentre Hospitalier Régional d'Orléans — NA
Institut Pasteur — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Kyasanur forest disease.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for Kyasanur forest disease at this time.
New trials open frequently. Follow this disease to get notified.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Kyasanur forest disease.
Community
No community posts yet. Be the first to share your experience with Kyasanur forest disease.
Start the conversation →Latest news about Kyasanur forest disease
Disease timeline:
New recruiting trial: Virus Transmission to People Recently Bitten or With a History of Monkey Bites "SIMVIR
A new clinical trial is recruiting patients for Kyasanur forest disease
New recruiting trial: Neutralizing Power of Serum Antibodies - 2
A new clinical trial is recruiting patients for Kyasanur forest disease
New recruiting trial: Clinical and Biological Aspects of the MONKEYPOX Disease
A new clinical trial is recruiting patients for Kyasanur forest disease
New recruiting trial: Simian Foamy Virus Transmission to Humans
A new clinical trial is recruiting patients for Kyasanur forest disease
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.How severe is my case, and do I need to be hospitalized?,What warning signs should I watch for that would mean I need to come back to the hospital?,Is there a risk of the second phase of illness with brain involvement, and how will we monitor for it?,How long should I expect recovery to take before I can return to work or school?,Should my family members or close contacts be tested or monitored?,Should I or my family get the KFD vaccine to prevent future infections?,What precautions should I take to avoid tick bites in the future?
Common questions about Kyasanur forest disease
What is Kyasanur forest disease?
Kyasanur forest disease (KFD), sometimes called 'monkey fever,' is a rare viral illness caused by the Kyasanur forest disease virus (KFDV), a member of the flavivirus family. It is spread to humans primarily through the bite of infected hard ticks (mainly Haemaphysalis spinigera), though contact with blood or tissues of infected animals, especially sick or dead monkeys, can also transmit the virus. The disease typically begins suddenly with high fever, severe headache, body aches, and muscle pain. Within the first few days, patients may experience bleeding from the gums, nose, or gastrointest
How is Kyasanur forest disease inherited?
Kyasanur forest disease follows a sporadic inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
Which specialists treat Kyasanur forest disease?
16 specialists and care centers treating Kyasanur forest disease are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.