Kyasanur Forest Disease (KFD) is a viral hemorrhagic fever that people get after a bite from an infected tick in or near forested areas. The virus belongs to the flavivirus family (the same large family that includes dengue and Zika, though KFD is different). The infection typically starts suddenly with high fever, chills, headache, intense tiredness, and body aches. Some people have nausea, vomiting, abdominal pain, and red, irritated eyes. Because this virus can affect blood vessels and clotting, nosebleeds, gum bleeding, or vomiting blood can occur in more serious cases. After improvement, a second phase can occasionally appear with brain and nerve symptoms (for example, confusion or fits). There is no person-to-person spread, so family members usually get infected separately from tick exposure in the environment, not from the patient. The disease is mostly recorded in the Western Ghats of India where the ticks and animal hosts live. Clinicians treat KFD with supportive hospital care—fluids, careful monitoring, blood products if needed, and management of complications—while the body clears the virus. CDCMDPIPMC+1
Kyasanur Forest Disease (KFD), sometimes called “monkey fever,” is a viral disease that people mostly get in the forested hills of southern India, especially along the Western Ghats. It is carried by hard ticks that feed on wild animals and sometimes bite humans. People usually get infected after a tick bite or after handling a sick or recently dead monkey. There is no proven human-to-human spread in the community. A vaccine exists for people living in high-risk areas. CDCniv.icmr.org.in
KFD is caused by the Kyasanur Forest Disease virus (KFDV), a member of the Flaviviridae family (the same large family that includes dengue and Zika). The virus lives in a forest cycle among ticks, small mammals, and monkeys. Haemaphysalis ticks are the main vectors in India; H. spinigera is especially important, but other tick species can also carry the virus. Ticks can pass the virus from one life stage to the next (transtadial) and from mother tick to eggs (transovarial), which helps the virus persist in nature. PMCniv.icmr.org.inBioMed Central
How common and how severe? In most years, a few hundred people are reported to get KFD, mainly in Karnataka, Goa, Maharashtra, Kerala and Tamil Nadu. The case-fatality rate varies by outbreak and by the group affected; older summaries put it around 3–5%, and some recent reports suggest about 2–10% depending on the year, location, and access to care. CDCCDC Stacksniv.icmr.org.in
Incubation and course of illness. Most people become sick 3–8 days after an infectious tick bite. The illness often starts suddenly with high fever and severe body aches. A subset of patients develop a “biphasic” illness—after the first fever settles, a second phase may occur with neurologic symptoms such as confusion or tremors. Bleeding can happen in either phase. niv.icmr.org.inPMCScienceDirect
Kyasanur Forest Disease is a tick-borne viral fever that people catch mainly in forest areas of southern India. The virus is spread to people by the bite of infected ticks or after contact with sick or dead monkeys. The disease can be serious, sometimes causing bleeding or brain involvement, but most people recover with supportive care. Vaccination is available in risk areas. CDC
Types
Doctors don’t use strict “official subtypes,” but in real life KFD tends to show several patterns. Thinking in these simple “types” helps patients and families understand what is happening:
Typical (monophasic) febrile KFD
This is the most common pattern: sudden high fever, severe headache and body pain, prostration (profound weakness), and tummy symptoms like nausea or loose stools. It lasts about 5–12 days and then improves. Some bleeding signs (like nose or gum bleeding) can appear early. niv.icmr.org.inBiphasic KFD
About 10–20% of patients get better after the first fever and then, around week 2, develop a second phase with renewed fever and nervous-system symptoms (e.g., confusion, drowsiness, tremors). PMCHemorrhagic-predominant KFD
Here the standout features are bleeding (from nose, gums, vomiting blood, or blood in stools), easy bruising, or very low platelets. This pattern needs close monitoring for shock. niv.icmr.org.inNeurologic-predominant KFD
Some patients mainly show brain and nerve signs—neck stiffness, altered behavior, tremors, seizures, or meningo-encephalitis. PMCSubclinical/serologic KFD (less commonly noticed)
Blood surveys in some areas have found people with antibodies to KFDV who don’t remember a clear illness. This suggests that mild or unnoticed infections can occur. PMC
Causes
In infections like KFD, “causes” really mean the ways you come into contact with the virus and the situations that make infection more likely.
Tick bites in forests
The number-one cause is a bite from an infected Haemaphysalis tick in forested or plantation areas. Nymph-stage ticks are especially likely to bite humans. niv.icmr.org.inHandling sick or recently dead monkeys
Monkeys get very sick and often die. Their bodies can carry many infected ticks, creating local “hot spots.” Touching or moving carcasses can expose people to ticks. niv.icmr.org.inLiving or working near forest edges
Villages, farms, and homes close to the forest have higher tick exposure, especially during peak tick seasons. CDCAreca nut, paddy, or plantation work
Plantation belts and harvested fields can harbor infected tick larvae and nymphs, raising risk for farmers and laborers. BioMed CentralCollecting firewood, honey, or forest products
Frequent forest visits increase tick encounters.Grazing or moving cattle through forest fringes
Cattle help maintain large tick populations, bringing ticks from forest to homesteads. niv.icmr.org.inSleeping or resting on forest floor or leaf litter
Ticks quest on low vegetation and leaf litter; sitting or sleeping there raises exposure.Peak season (roughly Nov–May, local variation)
Tick activity, especially nymphs, is highest during the dry months after monsoon—this drives outbreaks. niv.icmr.org.inNo or incomplete vaccination in risk zones
The inactivated KFD vaccine is offered in endemic districts; skipping doses leaves people unprotected. niv.icmr.org.inDeforestation and land-use change
Disturbed habitats can shift animal–tick–human contacts, sometimes amplifying risk. PMCCarrying ticks home on clothes or on animals
Ticks hitchhike on clothing, firewood, pets, or livestock, then bite later.Not using tick repellents or protective clothing
Bare legs, open sandals, and short sleeves allow ticks easy access.Handling monkeys without gloves or repellent
Traditional or curious handling of dead/sick monkeys increases tick exposure. niv.icmr.org.inWorking in new outbreak “hot spots”
After a monkey dies, many infected ticks drop where it fell; people entering that spot are at higher risk. niv.icmr.org.inChildren playing outdoors in forested hamlets
Kids may sit on ground or handle leaves/wood, which carry questing ticks.Collecting water or forest fodder at dawn/dusk
Ticks are active when people also move for daily chores in some communities.Hiking or tourism in endemic reserves
Forest trekking without repellent or long clothing raises risk.Transovarially infected local tick populations
When tick mothers pass virus to eggs, entire areas can stay infected year to year. BioMed CentralNatureLack of community awareness about monkey deaths
Not reporting or avoiding areas with recent monkey deaths can increase exposure. niv.icmr.org.inLaboratory exposure (rare, occupational)
KFDV is a high-risk pathogen; past lab infections happened before strict biosafety rules. niv.icmr.org.in
Common symptoms
Most patients have a sudden, “flu-like” start. A smaller group later develops bleeding or brain-related (neurologic) problems.
High fever — abrupt onset, often reaching ~39–40 °C (102–104 °F). niv.icmr.org.in
Severe headache — often frontal; patients describe it as “intense.” niv.icmr.org.in
Severe body and muscle aches — the whole body feels sore; touching muscles can be painful. niv.icmr.org.in
Extreme weakness (prostration) — people feel “wiped out” and may not be able to stand or work. niv.icmr.org.in
Nausea and vomiting — common early stomach symptoms. niv.icmr.org.in
Diarrhea — sometimes watery, adding to dehydration risk. niv.icmr.org.in
Cough — persistent in some; rarely with blood-tinged sputum. niv.icmr.org.in
Bleeding signs — nose or gum bleeding, vomiting blood, or blood in stools; bruises may appear easily. niv.icmr.org.in
Dizziness or low blood pressure — due to dehydration or bleeding; may signal shock in severe cases. niv.icmr.org.in
Neck stiffness — a warning sign for meningeal (brain lining) irritation. PMC
Confusion or disorientation — part of the neurologic phase in some patients. PMC
Tremors or abnormal reflexes — the nervous system is irritated or inflamed. niv.icmr.org.in
Seizures or loss of consciousness (rare but serious) — need urgent care. PMC
Tender muscles and light sensitivity (photophobia) — common in the first week. niv.icmr.org.in
Mouth lesions on the soft palate — small blister-like spots reported in many cases. niv.icmr.org.in
Diagnostic test
Doctors do two things at once: (1) look for signs of KFD and its complications, and (2) confirm the virus with lab tests. Because other illnesses (like dengue, malaria, typhoid, leptospirosis, rickettsioses) look similar, doctors also test to rule out those diseases.
A) Physical examination
Vital signs — temperature, pulse, blood pressure, breathing rate, and oxygen level. High fever is typical; low blood pressure or fast pulse can signal dehydration or bleeding.
Skin and mucosa check — doctors look for petechiae (pinpoint spots), bruises, gum/nose bleeding, or blood in vomit/stool.
Hydration and shock assessment — dry tongue, sunken eyes, poor urine output, cold limbs suggest significant fluid loss.
Neurologic exam — level of alertness, orientation, strength, reflexes; helps pick up meningitis/encephalitis early. niv.icmr.org.in
B) “Manual” bedside tests
Kernig’s sign — pain/resistance when the knee is extended with the hip flexed; suggests meningeal irritation.
Brudzinski’s sign — neck flexion produces hip/knee flexion; another sign of meningitis.
Glasgow Coma Scale (GCS) — a simple bedside score for how awake and responsive a person is. Lower scores mean more severe brain involvement.
Orthostatic (postural) blood pressure & capillary refill — quick checks for dehydration or blood loss leading to circulatory compromise. (These bedside tools guide urgency of care in viral hemorrhagic fevers like KFD.) PMC
C) Laboratory & pathological tests
Complete blood count (CBC) — low platelets (thrombocytopenia) and low white cells (leukopenia) are common; anemia can appear with bleeding.
Liver tests (ALT/AST, bilirubin) — can be elevated because KFD affects many organs.
Kidney panel & electrolytes — track dehydration, shock, or organ stress.
Coagulation profile (PT/INR, aPTT, fibrinogen) — looks for bleeding risk or coagulopathy.
RT-PCR for KFDV (blood) — the most useful test in the first week; detects the virus’s RNA, usually up to about day 8 from symptom onset.
KFDV-specific IgM ELISA (blood) — turns positive from about day 5 and stays detectable for weeks to months; useful when PCR turns negative.
KFDV-specific IgG ELISA — shows past exposure or later-phase infection; may help in paired samples.
CSF analysis (if neurologic signs) — in suspected meningitis/encephalitis, lumbar puncture can show inflammation; specialized PCR/antibody tests may be done on CSF in reference labs. niv.icmr.org.in
Notes for #13–15: National guidance in India uses real-time RT-PCR in the acute phase and IgM ELISA after day 5; virus isolation is restricted to high-biosafety labs. niv.icmr.org.in
D) Electrodiagnostic/monitoring tests
EEG (electroencephalogram) — if there are seizures or altered awareness, EEG helps document brain irritation or seizure activity in the biphasic/neurologic form. PMC
ECG (electrocardiogram) — monitors heart rhythm during severe illness, shock, or major electrolyte shifts; helps guide fluids and electrolytes safely. (Supportive care is the mainstay.) CDC Stacks
E) Imaging tests
Brain CT or MRI — used when there are strong neurologic signs; can help rule out bleeding in the brain or other causes of encephalitis. PMC
Chest X-ray (CXR) — not specific for KFD but useful if there is cough, blood-tinged sputum, or breathing difficulty, and to rule out other infections that mimic KFD. niv.icmr.org.in
Non-pharmacological treatments (therapies & supportive measures)
These measures do not kill the virus but help your body cope and prevent complications. They are used alongside any medicines a clinician prescribes.
Early medical assessment and observation: allows prompt fluids and bleeding management before complications escalate. PMC
Strict rest: lowers energy demand and helps recovery during high fever.
Oral rehydration solution (ORS) sips frequently if you can drink; IV fluids if you cannot—prevents shock and protects kidneys. PMC
Fever comfort care: tepid sponging, light clothing, cool room—not ice baths.
Bleeding precautions: soft toothbrush, avoid nose-picking/straining, no intramuscular injections unless essential, gentle handling to reduce bruising. Frontiers
Fall-prevention and supervision if dizzy or weak; lowers injury/bleeding risk.
Nutrition support: small, frequent, easily digested meals (khichdi, soups, bananas, rice, curd if tolerated) to prevent weakness.
Nausea control routines: tiny sips, bland foods; sit upright after eating; clinician may add antiemetic.
Mouth and skin care: keeps mucosa intact and lowers secondary infection risk.
Careful tick removal (if present): use fine tweezers close to skin, pull steadily; clean site with soap/water; don’t crush the tick with fingers. (Prevents additional pathogen exposure.) CDC
Avoid aspirin/ibuprofen/NSAIDs unless a clinician approves (bleeding risk). Use paracetamol/acetaminophen instead when advised. Frontiers
Avoid unnecessary invasive procedures (catheters, injections) when platelets are low. Frontiers
Monitor urine output (aim for pale yellow urine)—helps catch dehydration early.
Family protection counseling: how to prevent new tick bites for caregivers visiting forest areas (repellent, clothing, tick checks). CDC+1
Psychological reassurance and sleep hygiene: illness anxiety worsens fatigue; quiet, dark room helps.
Temperature and vital-sign logs: simple charts help teams spot deterioration early.
Positioning and breathing exercises if weak; prevents atelectasis and improves comfort.
Hygiene and hand-washing: reduces secondary infections; ordinary precautions suffice since KFD is not spread person-to-person. CDC
Hospital observation for red flags (bleeding, confusion, severe vomiting). Early escalation saves lives. PMC
Discharge education (bleeding warning signs, hydration, tick avoidance) to prevent relapse-related harm and future exposures. CDC
Drug treatments
There is no approved antiviral for KFD; therapy is supportive. Doses below are typical adult ranges—clinicians adjust for age, weight, pregnancy, liver/kidney function. Do not self-medicate. PMCCDC
Paracetamol (acetaminophen) – Analgesic/antipyretic
Dose: 500–650 mg by mouth every 6–8 h (max generally 3,000 mg/day unless clinician sets differently).
Purpose: Lowers fever, eases headache/body pain.
Mechanism: Inhibits central prostaglandin synthesis.
Side effects: Rare liver toxicity if overdosed or with heavy alcohol use.
Why preferred: Safer for bleeding risk than NSAIDs. Frontiers
Ondansetron – Antiemetic (5-HT3 antagonist)
Dose: 4–8 mg PO/IV every 8–12 h as needed.
Purpose: Controls nausea/vomiting so you can hydrate.
Side effects: Headache, constipation; rare QT prolongation.
Proton pump inhibitor (e.g., Pantoprazole) – Acid suppression
Dose: 40 mg PO/IV once daily.
Purpose: Protects stomach lining in patients at bleeding risk or on stress prophylaxis.
Mechanism: Blocks gastric proton pumps.
Side effects: Headache, low magnesium with prolonged use.
IV crystalloids (e.g., Normal saline, Ringer’s lactate) – Volume support
“Dose”: Rate is individualized to vitals/urine output.
Purpose: Corrects dehydration, maintains blood pressure.
Risks: Fluid overload if given too fast—requires monitoring. PMC
Antacids/H2 blockers (if PPIs not used) – GI protection
Dose: as directed (e.g., famotidine 20 mg twice daily).
Purpose: Reduce GI irritation/bleeding risk.
Antibiotics (targeted only if secondary bacterial infection is suspected) – Antibacterial
Purpose: Treats bacterial pneumonia/UTI/sepsis if present.
Note: Does not treat the KFD virus. Choice depends on cultures and local protocols.
Anticonvulsants (e.g., levetiracetam) – Seizure control in encephalitic phase
Dose: per neurologist (e.g., 500–1,000 mg twice daily; IV loading in status).
Purpose: Prevents further brain injury from seizures.
Side effects: Sleepiness, mood changes—clinician supervised.
Vitamin K – Coagulation support in selected cases
Dose: individualized (e.g., 5–10 mg IV/PO if INR prolonged due to functional deficiency).
Purpose: Helps liver-dependent clotting factors in certain coagulopathies.
Note: Not for everyone—only if tests show deficiency and clinician advises.
Blood products (platelets, FFP, packed RBCs) – Not drugs, but critical therapies
Use: For severe thrombocytopenia/active bleeding, coagulopathy, or significant anemia.
Risk/benefit: Life-saving when indicated; needs hospital monitoring. PMC
Investigational/under study antivirals (NOT standard):
Dietary, hydration, and “molecular” supplements
Supplements can support nutrition during recovery. They do not treat KFD. Discuss with your clinician, especially if pregnant, on blood thinners, or with liver/kidney disease.
Oral Rehydration Solution (ORS): small, frequent sips; purpose: replace fluids/electrolytes lost from fever/vomiting.
Electrolyte sachet (low-sugar): helps correct mild sodium/potassium losses when advised.
Vitamin C (200–500 mg/day): general immune support; antioxidant; can loosen stools in high doses.
Zinc (10–20 mg elemental/day for 10–14 days): supports mucosal immunity; helpful if diarrhea.
Vitamin D3 (1,000–2,000 IU/day): supports immune function if deficient.
B-complex (daily): supports energy pathways, especially with poor intake.
Folate (0.4–0.8 mg/day): supports blood cell production when diet is limited.
Protein supplementation (whey/legume-based): 20–30 g/day if oral intake is low; supports healing.
Omega-3 from food (fish, flax) or capsules (as per label): gentle anti-inflammatory support; stop before any procedures due to bleeding concerns—ask your doctor.
Probiotics (as labeled): may help appetite and gut comfort during recovery.
(Again: none of these replace medical care or prevent bleeding.)
Regenerative / stem-cell drug
There are no approved “immunity booster” drugs, regenerative medicines, or stem-cell therapies for KFD. Using such products outside clinical trials is not evidence-based and may be dangerous or costly without benefit.
The best immune protection specific to KFD is public-health vaccination in eligible people living in or entering vaccination zones, following state guidance, plus tick-bite prevention. ijmr.org.inCDC
If you see clinics advertising stem cells or “strong immunity injections” for KFD, avoid them and follow official health-department advice.
Are surgeries ever needed?
Surgery is not a treatment for KFD. Because KFD can cause bleeding, most procedures are avoided unless absolutely necessary. Rarely, doctors may need:
Airway intubation and ventilation (procedure, not surgery) if there is severe brain involvement or respiratory failure—to protect breathing.
Central venous line placement to give life-saving fluids/blood products when veins are collapsed.
Endoscopic therapy (not open surgery) to stop a bleeding stomach/duodenal vessel if massive GI bleeding occurs.
Emergency neurosurgical care (very rare) if there is a life-threatening brain bleed with pressure—high-risk, case-by-case.
Surgical control of uncontrolled peripheral bleeding from trauma (rare; avoided by caution and rest).
These are not routine and only happen in ICU-level care with full blood support.
Prevention pillars
Use tick repellents with DEET on exposed skin when entering risk forests. CDC
Treat clothing/gear with 0.5% permethrin or buy pre-treated clothing; this significantly lowers tick bites. CDCGillings School of Public Health
Wear tick-smart clothing: long sleeves, long pants tucked into socks, closed shoes, light colors to spot ticks. CDC
Walk in the center of trails; avoid brushing against vegetation. CDC
Daily tick checks after outdoor work; shower soon after; remove ticks promptly with tweezers. CDC
Avoid handling dead/sick monkeys; report monkey deaths to local health/forest teams. CDC
Community tick control on cattle/dogs with veterinarian-recommended acaricides in affected villages. PMC
Follow vaccine advice from state health authorities if you live in or travel to vaccination zones (two doses + booster per program). ijmr.org.in
Clear leaf litter/brush around homes at forest edges; keep sleeping areas off the ground. CDC
Seasonal awareness: heed local alerts during outbreak months and seek care early if fever appears after forest exposure. niv.icmr.org.in
When to see a doctor (don’t wait)
Fever with severe headache/body pain after forest/plantation exposure in an affected district.
Any bleeding (nose/gums, black stools, vomiting blood), persistent vomiting, or dizziness/fainting.
Confusion, seizures, severe weakness, or low urine output.
Elderly, pregnant people, children, or those with chronic illness should seek care early. Frontiers
What to eat (and what to avoid):
Eat more of:
Fluids/ORS, water, soups—steady sipping all day.
Easy-to-digest carbs (rice, porridge, toast, bananas) to keep energy up.
Light proteins (dal, eggs, curd/yogurt if tolerated, fish/chicken soups) to help repair.
Fruits/veggies that are soft and peeled/cooked (bananas, stewed apple, carrots) for vitamins.
Small, frequent meals if nausea is present.
Avoid/limit:
- Aspirin/NSAIDs-based “cold & flu” combos unless your doctor says otherwise (bleeding risk). Frontiers
- Alcohol (dehydrates and stresses the liver).
- Very spicy/fried foods (can worsen nausea).
- Raw or unpasteurized foods if hospitalized or very weak (infection risk).
- Huge meals—they often trigger vomiting; choose gentle portions.
The KFD vaccine—plain facts
Vaccine used by Indian state programs is a formalin-inactivated tissue-culture vaccine.
Program schedule has typically been two primary doses (about a month apart), booster at 6–9 months, and annual/periodic boosters thereafter per local policy.
Coverage/effectiveness vary by campaign and adherence; it helps but doesn’t guarantee protection, so tick precautions still matter.
Ask local health officials (district surveillance team/PHC) about who qualifies, where to get it, and current booster schedules in your area. niv.icmr.org.inijmr.org.inPMC
Frequently Asked Questions (FAQ)
1) Is KFD the same as dengue?
No. Both can cause fever and bleeding, but KFD is tick-borne and occurs in Western Ghats forests; dengue is mosquito-borne in urban/rural settings. Tests are different. CDC
2) Can I catch KFD from a sick family member?
No. There is no person-to-person spread documented. People in the same family get infected from tick exposure in the same environment. CDC
3) How soon after a tick bite do symptoms begin?
Usually 2–8 days. If you develop fever/headache after forest exposure, seek care. Frontiers
4) What tests confirm KFD?
RT-PCR early in illness and/or ELISA for IgM/IgG antibodies later. CDC
5) Is there a cure or a specific antiviral?
Not at present. Supportive hospital care saves lives. Antivirals remain investigational. PMCPreprints
6) What is the usual outcome?
Many recover with supportive care; some develop severe bleeding or neurologic complications. Reported fatality has often been in low single digits in many series, but risk varies by outbreak, care access, and patient factors. CDC Stacks
7) Should I take antibiotics “just in case”?
No. Antibiotics do not treat viruses. Doctors use them only if there is clear evidence of bacterial infection.
8) Are painkillers safe?
Use paracetamol/acetaminophen as advised. Avoid aspirin/ibuprofen/other NSAIDs unless a clinician specifically recommends them because of bleeding risk. Frontiers
9) I live in an affected village. How do I protect my family?
DEET repellent, permethrin-treated clothing, daily tick checks, report monkey deaths, and follow vaccine drives if eligible. CDC+1ijmr.org.in
10) Do pets or cattle spread KFD?
Livestock and dogs can carry ticks closer to homes, raising exposure. They seldom infect humans directly. Acaricide tick control helps. CDCPMC
11) Can children or pregnant women get vaccinated?
Eligibility, timing, and contraindications are set by local health authorities; consult your PHC/district team for the current policy in your state. niv.icmr.org.in
12) What if I find a tick on my skin?
Remove with fine tweezers (close to the skin, steady pull), clean with soap/water, and watch for fever. Do not burn or apply kerosene; don’t crush ticks with fingers. CDC
13) Does prior KFD infection protect me forever?
Long-term protection is not fully defined. Follow current vaccine/precaution advice even after recovery.
14) Are there community-level controls?
Yes—tick control on cattle/dogs, IEC (information/education) activities, ring vaccination around outbreak sites, and forest-edge habitat management. PMCniv.icmr.org.in
15) Where can I get reliable updates?
Follow your state health department and district surveillance unit advisories; for general information, see CDC pages on KFD and peer-reviewed reviews. CDCPMC
Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.
The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members
Last Updated: August 17, 2025.
