About Kyasanur Forest Disease

Key points

  • Kyasanur Forest Disease (KFD) is a viral disease mostly found in southern India.
  • Spread to people primarily occurs through tick bites or contact with infected animals.
  • KFD can be fatal.
  • There is a vaccine available for people at risk for KFD.
  • Between 400 and 500 people get KFD every year.
A grey bonnet macaque walks along a road next to a forest.

What it is

Kyasanur Forest Disease (KFD) is a serious disease first identified in the Kyasanur Forest of India. It is caused by the KFD virus. Hard ticks (Hemaphysalis spinigera) spread the KFD virus to people and to animals, like monkeys and rodents.

Map showing the areas where Kyasanur Forest Disease can be found.
KFD is found in the Karnataka, Tamil Nadu, and Kerala states of India.

Signs and symptoms

Most people with KFD have a sudden onset of chills, fever, and headache. Severe muscle pain, vomiting, gastrointestinal symptoms, and bleeding can follow 3 or 4 days after symptoms begin.

Most patients recover one to two weeks after symptoms begin. About 10 to 20% of patients experience a second wave of symptoms, including severe headache, mental disturbances, tremors, and vision problems.

How long it takes for signs to show

People with KFD usually start having symptoms 3-8 days after being infected with the virus.

Risk factors

Hunters, herders, forest workers, and farmers in the Karnataka, Tamil Nadu, and Kerala states of India are at higher risk for getting KFD. This is because they are more likely to be bitten by infected ticks.

Travelers visiting a location with known or history of KFD spread are at risk of infection.

People are more likely to get KFD during the dry season of November to June.

How it spreads

  • People get KFD from infected tick bites or exposure to an infected animal.
  • Infected ticks can live on livestock, but livestock rarely spread KFD to people.
  • KFD does not spread between people.
A graphic showing the transmission cycle of the KFD virus
The KSD virus spreads from ticks to animals and people

Prevention

To prevent KFD:

  • Use insect repellent containing DEET to prevent tick bites.
  • Get vaccinated if you live in an area where KFD is found.
  • Avoid contact with dead or sick animals, particularly monkeys.
Keep Reading: Preventing Tick Bites

Testing and diagnosis

Healthcare providers diagnose KFD with the following tests:

  • Polymerase chain reaction (PCR)
  • Virus isolation
  • Detection of antibodies in the blood

Treatment and recovery

There is no cure for KFD.

Supportive care is crucial, including fluid balance, providing oxygen, managing blood pressure, and treating additional infections.

With quick medical care, many patients recover from KFD without complications. However, about 3 to 5% of people with the disease will die.

Vaccines

A vaccine for KFD is available and recommended in the parts of India where KFD is found.

What CDC is doing

CDC is monitoring the spread of KFD. CDC also provides guidance on prevention and management of KFD to international public health partners.

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