ACUTE FLACCID PARALYSISKANISHK DEEP SHARMAROLL NO. 50

DEFINITIONSudden onset of weakness or paralysis over a period of 15 days in a patient aged less than 15 years age

DDX

POLIOMYELITISNon enveloped, positive stranded RNA virusGenus ENTEROVIRUS family PICORNAVIRIDAE3 antigenically distinct serotypes:-1,2,3

•Entry into mouth.•Replication in pharynx, GI tract, Local Lymphatic.•Hematologic spread to lymphatic and central nervous system.•Viral spread along nerve fibers.•Destruction of motor neurons

PATHOGENESIS

IMMUNITY•Initially protected by maternal antibodies for first few weeks of life

TYPES• Asymptomatic• Abortive Polio • Non-paralytic • Paralytic

• Spinal• Bulbar• Bulbospinal

CF- ASYMPTOMATIC• Accounts for approximately 95% of cases • Virus stays in intestinal tract and does not attack the nerves • Virus is shed in the stool so infected individual is still able to infect others

CF-ABORTIVE•Does not lead to paralysis •Mild symptoms seen such as sore throat, fever, n/v, diarrhea, constipation ( Minor illness) •Most recover in <1 week

CF- NON PARALYTIC( Major illness) – Occurs in 1-2% of polio infections – Symptoms are stiffness in the neck, back, and/or legs – Increased or abnormal sensations can occur– Complete recovery after 2-10 days of symptoms

CF- PARALYTICParalytic Polio Fewer than 1% of those infected develop this type Acute flaccid paralysis seen. Initially focal but spreads over 3 – 4 days Headache, neck/back stiffness, unusual sensations, increased sensitivity to touch Tripod sign + Descending paralysis Asymmetrical patchy paralysis Deep tendon reflex lost before onset of paralysis

SPINAL POLIOMost common form of paralytic79% –Attacks motor neurons and causes paralysis of muscles of respiration and muscles of extremities Children <5 years most likely to become paralyzed in one leg Adults are most commonly paralyzed in both arms and legs Those affected still retain sensation in extremities

BULBAR POLIO• Accounts for 2% of paralytic polio • Virus attacks motor neurons in brainstem •Affects cranial nerve function •Primarily inhibits ability to breathe, speak, and swallow effectively Facial asymmetry present

BULBOSPINAL POLIO•Accounts for 19% of paralytic cases • Affects extremities and cranial nerves • Leads to severe respiratory involvement

DDX CHARACTERISTICS•Asymmetric AFP•Fever & muscle pain at onset•Rapid progress, from onset to max. paralysis in <4days•Intact sensory function•Residual weakness/paralysis after 60 days

TREATMENT IN PASTIron Lung a sealed chamber with an electrically driven bellows that regulates breathing.

PRESENT TREATMENT• Antibiotics for infection • Analgesics for pain • Portable Ventilators for breathing problem • Moderate Exercise • Nutritional Diet

PREVENTION

•Oral polio vaccine• Formed by sabin • Produces both Humoral & local immunity Contributes to

herd immunity• 50% immune after 1 dose• >95% immune after 3 doses• Immunity probably lifelong

•Inactivated polio vaccine• Humoral immunity and to some extend pharyngeal immunity• Duration of immunity not known with certainty

STRATEGIES FOR POLIO

ERADICATION

Global Polio Eradication Initiative launched in 1988 Polio cases have decreased by over 99%1988 - >125 countriesIn 2010 - 4 countries The remaining countries are Afghanistan, India, Nigeria and Pakistan

CORE STRATEGIES1. High infant immunization coverage with four doses of

oral poliovirus vaccine (OPV) in the first year of life 2. Supplementary doses of OPV to all children under five

years of age during national immunization days3. AFP surveillance among children under fifteen years of

age4. Targeted “mop-up” campaigns once wild poliovirus

transmission is limited to a specific focal area.

IMMUNISATION IN INDIA

POLIO VACCINATION UNDER UIPOPVº birth OPV1 6 wks OPV2 10 wks OPV3 14 wks OPV4 16-24 Months

PULSE POLIO IMMUNIZATION (PPI)The supplementary immunization activities (SIAs) in India launched in 1995Irrespective of the immunisation status Usually Dec & Jan – Peak transmission

AIMProviding additional OPV doses to every child aged <5 years at intervals of 4-6 weeks during National Immunization Days (NIDs) & sub-National Immunization Days (SNID's) “Flood” the community with OPV within a very short period of time, thereby interrupting transmission of virus throughout the community. Intensification : house-to-house “search and vaccinate” component.

OUTBREAK RESPONSE IMMUNIZATION (ORI)House-to-house immunization following the AFP case investigation and stool specimen collection

ACTIVE CASE SEARCHWhere an AFP case resides – or where an AFP case has visited during the incubation period for polio (4-25 days before paralysis onset) Carried out immediately along with ORIA search is conducted for any children aged <15 years who have had the onset of flaccid paralysis within the preceding 60 days All cases that are found are investigated immediately, with collection of two stool specimens before administration of OPV.