Kyasanur forest disease (KFD) is a tick-borne viral (Flaviviridae family) hemorrhagic fever. KFD is a CDC Category C bioterrorism agent. If KFD were to be weaponized, the most likely method of dispersal would be by aerosol release.

The incubation period of KFD is 2-9 days. Whether acquired naturally or as a result of a bioterrorist attack, the initial symptoms of KFD include the sudden onset of fever, chills, headache, prostration, arthralgia, generalized lymphadenopathy, myalgia, and facial flushing. Petechiae may also be noted. After 72 hours, 40% of victims develop diarrhea and vomiting in addition to hemorrhaging from the nose, gums, and intestines. Ocular manifestations include conjunctivitis and photophobia. The soft palate typically has vesicles.

The initial phase lasts 6-11 days, after which the patient may have an afebrile period of 1-3 weeks followed by development of CNS involvement including confusion, delirium, seizures, and coma.

There are no known cases of person-to-person transmission; however, transmission via exposure to infected body fluids and inhalation of infectious aerosol has been documented.

KFD is endemic to areas of India. A tick-borne encephalitis vaccine is available in Russia but has not been approved in the United States.