16-08-2012, 03:46 PM
REBIES
REBIES.ppt (Size: 29 KB / Downloads: 152)
INTRODUCTION
Rabies is a viral disease, caused by rhabdovirus.
Rabies infects the central nervous tissue and salivary gland.
Rabies remains one of the most common viral causes of mortality in the developing world.
Epidemiology:
Rabies is currently distributed worldwide except for Antarctica and a few island nations.
The epidemiology of human rabies reflects that of local animal rabies,most human cases result from dog bites.
The World Health Organization (WHO) estimates that 55,000 humans die of rabies annually.
Pathogenesis
Rabies infection begins with centripetal spread of the virus via peripheral nerves to the CNS, and peripheral nerves to many tissues .
After entering through a break in the skin, across a mucosal surface, or through the respiratory tract, virus replicates in muscle cells, and in so doing it infects the muscle spindle. It then infects the nerve that innervates the spindle and moves centrally within the axons of these neurons. Pathogenesis:
Replication occurs in peripheral neurons and prior to its arrival in spinal cord neurons, confirming its transport within sensory neurons.