Poliomyelitis and Post Polio Syndrome. S.M. Mazloumi MD Associate professor

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1 Poliomyelitis and Post Polio Syndrome S.M. Mazloumi MD Associate professor

2 What is Poliomyelitis? polio= gray matter Myelitis= inflammation of the spinal cord This disease result in the destruction of motor neurons caused by the poliovirus. Polio is causes by a virus that attacks the nerve cells of the brain & spinal cord although not all infections result in sever injuries and paralysis.

3 POLIOMYELITIS Picornavirus 3 types: Poliovirus 1,2,3 Ingested, spread by faeco-oral route: Commoner in areas of poor sanitation Infants protected by maternal antibodies

4 History Associated with man since ancient times Egyptian hieroglyph indicates presence since 1400 BC Heinle characterizes poliomyelitis Poliomyelitis grey marrow in Greek Salk vaccine Sabin vaccine 1991 Molla produces polio in vitro from virus RNA 2002 completele synthetic production

5 Polio Eradication: Status in 1988

6 Polio Eradication: Status in 1998

7 Epidemiology Silent circulation Many hundreds may be infected prior to the development of a single case of paralysis WHO considers a single confirmed case of polio in an area of low occurrence an epidemic

8 How is polio transmitted? Poliovirus is transmitted through both oral and fical routes with implantation and replication occurring in either the orapgaryngeal and or in the intestine of mucosa. Polio cases are most infected for 7-10 days before and after clinical symptoms begin.

9 The unique stages of infection and pathogenesis of poliomyelitis. Poliovirus, an Enterovirus has an icosahedral capsid shell that protects it from digestion. GI Tract Blood Cord CNS Paralysis of motor neurons

10 Provocative Poliomyelitis Provocative poliomyelitis occurs when a person having polio virus circulating in blood (viraemia) receives any intramuscular injection. Reason is increased susceptibility of the relevant anterior horn cells resulting in settling of the circulating polio virus there and consequential paralysis.

11 What are the symptoms? Many include fever, pharyngitis, headache, anorexia, nausea, and vomiting. Illness may progress to aseptic meningitis and menigoencephalitis in 1% to 4% of patients. These patients develop a higher fever, myalia and sever headache with stiffness of the neck and back.

12 Clinical Pattern of Polio

13 Virus travels through blood and the nerves And each place in the cord that nerve cells are destroyed causes paralysis of that part of the body controlled by those motor neurons.

14 POLIO ATTACKS MOTOR NEURONES

15 Poliomyelitis:Clinical Features In 1% of cases virus invades CNS: Multiples and destroys anterior horn cells. In severe cases, poliovirus may attacks motor neurones in brainstem, leading to difficulty in swallowing, speaking and breathing

16 Equanous deformity Tibialis anterior muscle paralysis (most common) Heel elevated Toe gait Achill tendon contracture

17 Calcaneous deformity Gastrosoleous muscle paralysis (Cavous foot)

18 Varous deformity Peroneal muscle paralysis,associate with equanuse deformity (paralytic equano varous )

19 Planovalgus deformity Tibialis posterior paralysis ( Flat foot )

20 Paralytic Scoliosis Paravertebral muscleparalysis ( Pelvic title )

21 Knee deformities Hamstring muscle paralysis(geno recurvatum ) Quadriceps muscle paralysis ( knee flection contracture )

22 Treatment Intensive physiotherapy

23 Orthosis Treatment

24 treatment tenotomy osteotomy Tendon transfer arthrodesis Soft tisue release

25 Inactivated Vaccine Immunity to Poliovirus 1,2,3 Safe, effective Injection No gastrointestinal immunity: Risks of continued circulation of virus in endemic areas Expensive Jonas Salk

26 Live Vaccine Live attenuated oral vaccine (Sabin, 1961): Risks of viral mutation, leading to potential regain of virulence: Excretion of live virus thru faeces Live vaccine cheaper, and suitable for mass vaccination programmes

27 Poliomyelitis:Current Status Eradicated from developed world in 1960s Remains endemic in 7 countries Eradication plan by WHO by year 2000: not yet achieved, but progress is being made

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