Epidemiology Paralysis is the most devastating effect of polio virus infection Although 9095 infectionsubclinical Eradicated in most of countries except Nigeria Afghanistan and Pakistan Universal vaccination strategy and improved sanitation key factor in eradication ID: 918399
Download Presentation The PPT/PDF document "Poliomylitis Dr. Abbas Etiology" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Poliomylitis
Dr.
Abbas
Slide2Etiology
Slide3Epidemiology
Paralysis is the most devastating effect of polio virus infection
Although 90-95 % infection-subclinical
Eradicated in most of countries except Nigeria, Afghanistan and Pakistan
Universal vaccination strategy and improved sanitation: key factor in eradication
Slide4Transmission
Slide5Pathogenesis
Slide6Pathogenesis(contd..)
Vaccine strain of polio do not replicate in CNS.
Occasional
revertants
(by nucleoside
subtitution
) of these vaccine strain developed a
neurovirulent
phenotype and cause Vaccine acquired paralytic
poliomylitis
Reversion occur in small intestine and reaches to CNS via. Peripheral nerves
Slide7Infection
Traverse neural pathways and multiple site within CNS
Perineural inflammation and destruction
Petachial hemorrhages and inflammatory edema
Primarily infect motor neuron in anterior horn cells and medulla oblongata(cranial nerve nuclei)
Involvement of reticular formation that controlled vitals may have catastrophic out come
Pathogenesis(contd..)
Slide8Involvement of dorsal horn and dorsal root
ganglias
of spinal cord results in hyperesthesia and
myalgias:typical
of acute
polimyelitis
Other neuron affected are the
nuclie
in the
vermis
of cerebellum,
substantia
nigra,thatmus,hypothalmus
Slide9Clinical features
I.P- 8-12 days ,ranges from 5- 35 days
Infection with wild polio virus may follow several courses
Slide10Abortive poliomyelitis
Non specific flu like illness.
phgysical
examination
: non specific pharyngitis, abdominal or muscular tenderness and weakness
Recovery : complete without sequelae
Slide11Non- Paralytic poliomyelitis
Sign of abortive poliomyelitis but more intense
Headache, nausea, vomiting , sore throat, neck & spinal rigidity, fleeting paralysis of bladder and constipation.
Changes in Reflexes may precede before onset of paralysis
.
Superficial reflexes, cremastric, abdominal and reflexes of ,spinal, gluteal muscle.
Spinal and gluteal reflexes disappear before other reflexes
.
Changes in DTR occur after 8-24 hrs after superficial reflexes diminished.DTR are absent with paralysisSensory defect don’t occur in poliomyelitis
Recovery : complete
Slide12Paralytic poliomyelitis
Spinal
Bulbar
Encephalitis
Paralysis
Appears 3-8days after the initial symptoms
Clinical features of paralytic polio caused by wild or vaccine strain are comparable
Slide13Spinal paralytic polio
ist phase
Symptoms similar to abortive polio
Patient appear to feel better for 2-5 days
Biphasic disease
Severe headache and fever and exacerbation of previous symptoms.
Severe muscle pain sensory and motor phenomenon.
Physical examination: distribution of paralysis characteristically spotty
After 1-2 days asymmetric flaccid paralysis occur
Involvement of 1 leg is most common , followed by involvement of 1 leg and 1 arm
Proximal areas of the extremities tend to be involved to a greater extent.
Slide14Polio Paralysis
Some times biphasic phase absent.
50-60% cases h/o IM injection before paralysis(provocation paralysis)
Paralysis start .
Little recovery from paralysis noticed during ist few days but not beyond 6 months.
Return of strength and reflexes is slow and & may continue to improve as long as 18 months after the acute
ds
.
Atrophy of limb ,growth failure and deformity finally evident
Slide15Bulbar Polio
Dysfunction of cranial nerve and medullary centers without involving spinal cord
Respiratory difficulty, paralysis of extraoccular, facial and masticatory muscles.
1-nasal twang to the voice or cry.
2-inability swallow smoothly ,
3-absence of effective coughing
4-nasal regurgitation of saliva
5-deviation of palate, uvula, tongue
6-involvement of vitals centre in the medulla
7-paralysis of 1 or both vocal cords
8- Rope sign
: acute angulations b/w chin and larynx caused by weakness of hyoid muscle
Slide16Polioencephalitis
Rare form of disease
Higher centre of brain severely involved
Seizure, coma ,spastic paralysis, irritability, disorientation, drowsinesss,cranial nerve paralysis, deaths
Slide17Diagnosis
Paralysis in any unimmunized or partially immunized children
VAPP should be considered in any child with paralysis developed 7-14 days after receiving OPV.
Combination of fever ,headache, neck and back pain,assymmetric flaccid paralysis without sensory loss.
WHO recommends lab diagnosis of polio must be done by isolation and identification of polio virus in the stool ,with specific identification of wild –type and vaccine strains.
Slide18In suspected of poliomyelitis two stool sample collected 24-48 hrs apart
80-90% isolation of virus in acute phase.
< 20% isolation b/w 3-4 weeks
Ideally 8-10gm stool sample
Proper cold chain
Slide19Differential diagnosis
All causes of acute flaccid paralysis
Slide20AFP
Paralysis of acute onset
i.e
less than 4weeks and affected limbs are floppy or flaccid or limp.
Tone diminished, DTR diminished.
Sensation not affected
Case definition
: any child aged less than 15yrs who has acute onset flaccid paralysis for which no obvious cause(severe trauma, electrolyte imbalance) is found or paralytic illness in a person of any age in which polio is suspected
Slide21AFP
causes
Disorder of muscle: e.g.
polymyositis
, viral
myositis
Slide22Treatment only supportive
Slide23PreventionWHO recommends 4 strategy for global eradication of polio-1-routine vaccination2-NIDs
3-AFP surveillance
3- Mop-up immunization