Polio

epidemiology, prevention and control

1. POLIOMYELITIS

2. INDIAN SCENARIO H asn't reported any case - 13 Jan 2011 Declared POLIO Free – 27 March 2014 Following WHO strategies and – Conduction of PPI day every year High level routine immunization coverage Monitoring Improve surveillance of AFP Ensure rapid sample collection and investigation Follow up of all AFP,S for 60 days Conduct outbreak control

3. LATEST UPDATES “Polio virus found in Hyderabad “ P 2 strain from sewage sample Amber pet Sewerage treatment plant 16 June 2016 …… Times of I ndia WHO team probes “ suspected polio case “ In Uttar Pradesh 6yrs old boy in Balrampur District 18 June 2016 ………….. The Hindu

4. EPIDEMIOLOGICAL DETERMINANTS

5. P 2 component of tOPV is responsible for >60% of all vaccine DERIVEDPOLIO VIRUS (VDPV) in recent years *as of 10 June 2015; case count will be updated regularly ( current numbers: http :// www.polioeradication.org/Dataandmonitoring/Poliothisweek.aspx ) 7 P3 P1

6. Mode of transmission Faeco oral (main) usually in developing countries If hygiene good –water, food, flies If bad – finger Droplet infection (rare) in developed countries while acute phase of disease when virus is in throat Incubation period – 3 to 35 days

7. Unapparent (subclinical) – 91 to 96 % no symptoms appear Abortive polio (minor illness) 4 to 8 % self limiting Nonparalytic polio 1% synonymous to aseptic meningitis Paralytic polio <1% descending asymmetrical flaccid paralysis History of fever with paralysis is suggestive of polio Clinical spectrum

8. Tripod’s sign may be positive Deep tendon reflexes lost but no sensory loss Cranial nerves involved in bulbar & bulbospinal forms Causing facial asymmetry, dysphasia, dysphonia, respiratory insufficiency After acute phase – residual atrophied and paralyzed muscle Treatment –no such , physiotherapy

9. PREVENTION SOLE EFFECTIVE METHOD IMMUNIZATION

10. INACTIVED POLIO VACCINE SALK Discovered in 1995 Killed Formolized vaccine Made of WPV – Mahoney (salk type 1) MEF (salk type 2) Saukett (salk type 3) Final vaccine (trivalent) – Type 1 – 40 units Type 2 – 8 units Type 3 – 32 units Preservative – phenoxyethanol (0.5%) never thiomersal is used as incompatible with IPV Route - i.m (also s.c) Effect of temperature –in refrigerator – no loss of potency , in freezer potency decreases Available as stand alone product or with Diphtheria , Tetanus , Pertussis ,Hepatitis B , Hemophilus influenza In combinations alum is adjuent 4 inoculations are done – first 3 doses 1 to 2 month apart and fourth dose 6 to 12 months after third dose Disadvantage – protects only by paralytic polio, no local , no herd immunity, not suitable in epidemics Advantages – can be administered in immunocompromised , pregnancy , and age > 50 years ADR – erythema indurations tenderness at site of inoculation

11. ORAL POLIO VACCINE SABIN DISCOVERED IN 1957 Live attenuated virus ( type 1 ,2 ,3) Ideally to be given separately but for convenience is given trivalent (no efficacy favor) Vaccine = > 3,00,000 TCID 50 type1 , >1,00,000 TCID 50 type 2 , >3,00,000 TCID 50 TYPE 3 per dose As per national immunization schedule WHO 3 doses to be given 1 month apart recommended 1 st dose on 6 th week of life , 0 dose to all institutionally delivered child and booster in 16 to 24 months Dose mode – 2 drops Develops local intestinal as well as general immunity of individual ,and also heard immunity Colostrum milk – no effect but IgA during 1 st 3 days do effect Advantages – easy administration , humoral + intestinal + herd immunity , used in epidemics , inexpensive Disadvantages – type 3 mutant causes VAPP in recipients and contacts C/I in immunocompromised , leukemia's , malignancies , No harm in pregnancy but still IPV preferred

12. STORAGE 1) Stabilized – with MgCl heat stable 4 degree celsius 1 year , 25 degree celsius 1 month 2) Nonstabilized - heat unstable -20 degree deep freezed , and during transport dry ice or freezing mixture is used Repeated thawing and freezing decreases potency Potency indicated by VVM Earlier Human normal Ig 0.25 to 0.3 ml/ Kg protects for 3 weeks

13. National Immunization Schedule (OPV) 2 DROPS 0 dose – at birth or < 1 st 15 days 1 st dose – 6 th week 2 nd dose – 10 th week 3 rd dose – 14 th week Booster – 16 th to 24 th month Mr. Amitabh Bachchan –goodwill brand ambassador

14. BHUL NA JANA, BOOTH PE ANA

15. Single case - as epidemic Immediate active search for new cases ICMR has set National Enterovirus Units in Mumbai , Kasauli , Coonoor , Delhi , Chennai EPIDEMIOLOGICAL INVESTIGATIONS

16. CONTROL POLIO ERADICATION AND END GAME STRATEGIC PLAN 2013 – 2018 1) detect and interrupt all polio virus transmission 2) strengthen immunization system and withdraw OPV (switchover ) 3) containment and certification 4) legacy planning POLIO SURVEILLANCE

17. THANK YOU