(Three-day sickness, Stiff sickness) Arthropod transmitted viral disease of cattle characterised by rise in temperature, stiffness, lameness muscular tremor and a course of three days. It is recorded from Africa, Asia and Australia. It is caused by a bullet or cone shaped DNA virus namely Rhabdo virus which has got physical and chemical similarity with Vesicular stomatitis virus. This virus is sensitive to ether. Virus can produce intracytoplasmic inclusion bodies in infected cells. Virus has a close association with leucocyte-platelet fraction of blood. All breeds of cattle are susceptible but age group from six months to two years are more susceptible. The disease is not reported in goat, sheep, pig and dog. Morbidity rate may reach up to 100%. Transmission: Disease is mainly transmitted by sand fly belongs to Ceratopogonidae family but role of Culex and Culicoides mosquitoes are also proved. Direct contact will not lead to infection likewise any transmission through semen. More outbreaks noted in summer season. An amount of 0.002 mL blood leads to infection in hosts. Pathogenesis: Incubation period is about 2-10 days. Then a period of viraemia followed by localisation in mesodermal tissues like joints, muscle and lymph nodes. Course of the disease is only three days (if not complicated) and hence the name. Clinical signs: Rise in temperature (103-107˚F), shivering trembling, disinclination to move, arched back, salivation, nasal secretion and laccrimation are noticed. Muscles of the affected limb become stiff, hard and painful and laminitis cause shifting lameness. Grinding of teeth and groaning are other signs noted in recumbent animals. Abortion also noted. Lesions: Oedema of the lymph nodes, serofibrinous deposition in joints, congestion of lungs and necrotic changes in skeletal muscles. Diagnosis: Clinical findings and laboratory tests viz. CFT, FAT, AGID, ELISA and Virus isolation test. Mice or hamster is used for virus isolation and intra-cerebral inoculation is used. Virus can be detected in synovial fluid and mesothelial cells of synovial membrane. Cell lines using are BHK-21 or monkey kidney cell lines. Treatment: Symptomatic. Analgesics and antipyretics like sodium salycilate, phenyl butazone and diclofenac sodium can be used. A course of parentral antibiotics also should be given. Control: Vector control. Commercial vaccines are not available.
