A tropical disease, common in southern India, caused by a virus transmitted to man through the bite of the forest-dwelling tick Haemaphysalis spinigera. Symptoms include fever, headache, muscular pains, vomiting, conjunctivitis, exhaustion, bleeding of nose and gums and, subsequently, internal bleeding and the ‘necrosis of various tissues. General therapy, in the absence of specific treatment, involves relief of dehydration and loss of blood; analgesics are given to alleviate pain.