Poliomyelitis.pptx

Polio disease and its prevention and control

1. POLIOMYELITIS Dr. Dhruvendra Pandey Ass ociate Professor, Department of Community Medicine

2. From 125 Polio Endemic countries to 3 endemic countries Wild Poliovirus (WPV) Eradication, 1985–2019* Last type 2 polio in the world Last Polio Case in India Last type 3 polio In the world Eradication of WPV 2 10/17/22

3. Wild Poliovirus 1988

4. Wild Poliovirus 2008

5. Global WPV1 & cVDPV Cases1, Previous 6 Months Endemic country (WPV1) 10/17/22 WPV1 cases (latest onset) Afghanistan: 10 (10 Nov 2019) Pakistan: 61 (16 Nov 2019) cVDPV1 cases (latest onset) M yanmar: 4 (09 Aug 2019) Philippines: 1 (28 Oct 2019) Malaysia: 1 (30 Oct 2019) cVDPV2 cases (latest onset) Angola: 64 (21 Oct 2019) Benin: 6 (15 Oct 2019) C AR: 14 (06 Oct 2019) Chad: 1 (09 Sep 2019) DRC: 39 (21 Oct 2019) Ethiopia: 4 (09 Sep 2019) Ghana: 9 (23 Oct 2019) Nigeria: 7 (09 Oct 2019) Pakistan: 11 (03 Nov 2019) Philippines: 9 (25 Oct 2019) T ogo: 3 (16 Oct 2019) Z ambia: 1 (16 Jul 2019) 1 Excludes viruses detected from environmental surveillance ; 2 Onset of paralysis: 11 Jun 2019 – 10 Dec 2019

6. WPV1 cases (latest onset) Afghanistan: 22 (10 Nov 2019) Pakistan: 98 (16 Nov 2019) cVDPV1 cases (latest onset) Philippines: 1 (28 Oct 2019) Malaysia: 1 (30 Oct 2019) M yanmar: 6 (09 Aug 2019) cVDPV2 cases (latest onset) Angola: 71 (21 Oct 2019) Benin: 6 (15 Oct 2019) C AR: 16 (06 Oct 2019) Chad: 1 (09 Sep 2019) C hina: 1 (25 Apr 2019) DRC: 53 (21 Oct 2019) Ethiopia: 5 (09 Sep 2019) Ghana: 9 (23 Oct 2019) Niger: 1 (03 Apr 2019) Nigeria: 18 (09 Oct 2019) Pakistan: 11 (03 Nov 2019) Philippines: 9 (25 Oct 2019) Somalia: 3 (08 May 2019 ) Togo: 3 (16 Oct 2019) Z ambia: 1 (16 Jul 2019) Global WPV1 & cVDPV Cases1 , Previous 12 Months2 Endemic country (WPV1) 1 Excludes viruses detected from environmental surveillance; 2 Onset of paralysis 11 Dec 2018 – 10 Dec 2019 10/17/22 Public Health Emergency of International Concern First declared under the International Health Regulations in May 2014 Confirmed on 16 September 2019

7. Endemic Countries, 2014-19* cases 10/17/22

8. Pakistan/Afghanistan: Main Risks Ongoing transmission in the Southern & Northern corridors Accessing all children in highly mobile populations Impact of elections and sustaining government commitment at all levels Systemic weaknesses in EPI throughout many parts of both countries Resistance to vaccination (both overt and covert) In Afghanistan Bans on house to house campaigns in Southern Province Increasing inaccessibility in Eastern region Deteriorating security situation creating environment of fear Challenges in getting female front line workers particularly in high risk areas

9. Situation of Polio Eradication in India

10. Wild Poliovirus Cases, India P1 wild P3 wild No WPV case since January 2011 * data as on 7 December 2019 P2 wild 1600 1934

11. India - Major Milestones Achieved 2011 : Last polio case due to WPV (13 January, 2011) 2012 : Removed from list of polio endemic countries 2014 : Received polio-free certification on 27 March 2015 : Introduction of IPV in RI 2016 : tOPV - bOPV switch, 25 April 2016 Rukhsar , the last polio case due to wild poliovirus (WPV) in India !

12. 27 March 2014: South-East Asia Region of WHO certified polio-free

13. AFP Surveillance and Environmental Surveillance Status

14. India: Non-Polio AFP Rate, 2014-19* * Annualized for 2019 * data as on 7 December 2019

15. State-wise Non-Polio AFP Rate: 2017 - 19* 15 2017 8.92 * data as on 7 December 2019 8.11 2018 8.19 2019* * Annualized for 2019

16. India: Adequate Stool Sample Collection 2014-19* * data as on 7 December 2019 %

17. State-wise Adequate Stool Specimen Collection (%) 2017 - 19* 2018 86% 2017 86% * data as on 7 December 2019 2019 87%

18. * data as on 7 December 2019 Figure 7: Vaccine-derived Poliovirus in AFP cases, , India, 2009 - 2019 a-VDPV c-VDPV i-VDPV Vaccine-derived Poliovirus in AFP Cases, India, 2009 – 19*

19. Year Number of sewage sample collection sites Number of sewage samples collected Number of sewage samples with WPV Number of sewage samples with VDPV 2005 3 151 16 2006 3 24 2 2007 3 102 12 2008 3 156 32 2009 3 156 2 2 2010 8 297 20 1 2011 15 501 3 2012 17 742 9 2013 21 881 3 2014 23 947 12 2015 26 942 11 2016 35 1159 6 2017 42 1306 1 2018 46 1445 1 2019* 52 1407 States with existing environmental surveillance sites – 9 states * data as on 7 December 2019 Environmental Surveillance, India

20. INTRODUCTION Polio – Grey, Muellos – marrow ( Greek ) Acute viral infection, occurs mainly in children Caused by RNA virus Primarily infection of GIT It may infect CNS in < 1 % – May cause varying degree of paralysis First described - Michael Underwood -1789 First outbreak described in U.S. -1843 21,000 paralytic cases reported- U. S. - 1952 Global eradication in near future

21. HISTORY Heine - described Polio in 1840 Medin - in 1890 Hence called as Heine-Medin disease Landsteiner & Popper – Identified the virus in 1909 Enders, Robbibs, Waller– Cultivated the virus - Nobel Salk vaccine – Killed vaccine 1955 Sabin vaccine – Live attenuated vaccine in 1959

22. CONTD….. 2002- 1600 cases in 159 Districts 2003 – 225 cases in 87 Districts 2004 – 136 cases in 44 Districts 2005 – 66 cases in 35 Districts 2006 – 383 cases – Western UP , Bihar

23. EPIDEMIOLOGY - TREND It can occur sporadically, Endemically & Epidemically Earlier it was a sporadic disease Evolved as epidemic disease Earlier it was disease of infants, later started affecting older age group Earlier seen in temperate climate now in tropical climate also

24. A GENT Poliovirus – 3 serotypes 1, 2 & 3 – Type 1– Brunhilde, 2 – Lansing, 3 - Loen Most outbreaks - type 1 virus It can survive outside the human body for 4 months in cold season, 6 months – faeces Rapidly destroyed by pasteurization, chemical, physical agents, drying (not available in freeze dried form )

25. RESERVOIR OF INFECTION Man is the only source of infection Most cases – Mild, sub clinical – Play an imp. role in spread of the infection For every clinical case of Polio – 1000 sub clinical cases in children & 75 in adults Period of communicability – 7–10 days before & after the onset of symptoms

26. HOST Age – Infants & children Most vulnerable age – 6 months–3 years Sex – 3 males to 1 female Maternal antibody– Protect 6 months after birth Infection– Confers long lasting immunity, but no protection against another strain

27. FACTORS– PROVOCATE LATENT INFECTION Injection DPT (Vascularisation part spinal cord) Fatigue Trauma, Excercise Surgery Head & Neck region

28. ENVIRONMENT Likely to occur rainy season In India – 60 % cases – June – September Environmental sources – Contaminated water, food, through flies Over crowding, poor sanitation – Opportunity for infection

29. MODE OF TRANSMISSION Transmitted – Droplet infection, faeco–oral route Acute phase Faeco oral route – Later phase Fluids Foods Fruits & Vegetables Fomites Fingers Flies

30. PATHOGENESIS Portal of entry- Oral route. Adheres to the epithelial cells and replicates. Passes to the submucosa and replicates in Peyer`s patches & tonsils Travels to regional L.N. and gives rise to initial viraemia. Localization and replication occurs in R.E.Cells A second viraemia occurs with localization in different organs

31. PATHOGENESIS CNS infection- most likely to occur during viraemia either through muscle end plate or blood stream Virus detectable in oro-pharynx up to 3 weeks and in stool up to 12 weeks and up to 1 year in immuno- deficient patients In GIT, during replication, the oral polio virus can undergo mutation and convert into more neuro virulent phenotype

32. SUMMARY - PATHOGENESIS Entry into mouth Replication in pharynx, GI tract, local lymphatics Hematologic spread to lymphatics and central nervous system Viral spread along nerve fibers Destruction of motor neurons

33. CLINICAL SPECTRUM Infection with Polio virus Sub clinical infection 95 % Abortive infection 4 % Aseptic menin gitis 1 % Paralytic < 1 %

34. ASEPTIC MENINGITIS 1% cases CSF findings - raised proteins, normal sugar, pleocytosis (<1000 cells, Polymorphonuclear predominance) Lasting for 2-10 days. Non paralytic polio

35. PARALYTIC POLIO < 1% of cases. Occurring one or more days after symptoms of aseptic meningitis Sudden onset fever, vomiting, anorexia Back & neck muscle pain Followed by lower motor neuron paralysis (Flaccid)

36. CONTD….. Mild cases- Few muscles paralysed More proximal than distal Severe cases entire limb paralysed No sensory loss ( DD- GBS ) D eep T endon Reflexes (DTR) – Diminished 2-3 days full paralysis (Asymmetrical) Residual paralysis

37. INDIA 27-03-2014

38. BULBAR POLIOMYELITIS Fever, weakness swallowing, coughing Paralysis of pharynx Collection of secretion in the throat Inability to swallow threatens life Recovery good but slow ( If they survive )

39. POST POLIO SYNDROME New occurence of weakness, fatigue, fasciculations and pain with atrophy of groups of muscles involved in initial episode of paralysis May occur after 20-40 years May extend over 1-10 years Due to dysfunction and exhaustion of motor neurons that compensated for the neurons lost and not due to re-infection or reactivation .

40. DI A GNOSIS Isolation of the virus- Stool Virus cannot be grown in culture - from throat swab, CSF or Blood Rise in antibody titer – Confirmatory Aseptic meningitis- 1%. – With CSF revealing raised proteins, normal sugar, pleocytosis (<1000 cells, PMN predominance) Lasting for 2-10 days

41. POLIO VIRUS – ELECTRON MICROSCOPE

42. MANAGEMENT General supportive care Isolation Concurrent disinfection – Stool – 10 % Cresol Bed rest – avoid stress on affected muscles Paracetamol – Fever, Pain Prophylactic oral antibiotics Splints – to prevent deformity Fluid & electrolyte balance ( Oral ) Physiotherapy – After acute phase of illness – 6 weeks

43. DIFFERENTIAL DIAGNOSIS FOR POLIO Transverse myelitis No fever, symmetrical paralysis lower extremity, marked sensory loss, in children > 4 yrs., CSF – N Traumatic neuritis H/O IM injection, paralysis of limb with pain, Limb affected below knee, foot drop, slow recovery, any age group

44. DIFFERENCE – POLIO & GB SYNDROME POLIO MYELITIS Caused – virus Common – Infants, < 5 yrs Acute onset Fever present Flaccid, asymmetrical Descending No sensory deficit No cranial nerve involvement GB SYNDROME Demyelinating dis. Rare – Infants, 1-4 yrs Chronic Fever- 2-3 weeks prior Flaccid, symmetrical Ascending Sensory deficit present Cranial nerves involved – 7,9

45. PREVENTION Imm u n i z a tion i s t h e onl y w a y t o p r o t ect child r e n against polio All children by the age of 6 months– Fully immunized Both Killed & Live vaccines are available

46. POLIO VACCINE 1955 Inactivated vaccine 1959 Live attenuated vaccine 1987 Enhanced-potency IPV (IPV) It can be given with DPT, sero-conversion is better compared to OPV after 3 doses It can also prevent the multiplication of virus in the pharynx

47. INACTIVATED KILLED VACCINE Also known as Salk Vaccine Contains all 3 types – Polio virus 4 doses required – 1 st 3 when child 6 weeks old with 1-2 months interval 4 th dose – 6- 12 months after the 3 rd dose Additional doses every 5 years till the age of 18 years

48. CONTD….. Sabin 1957 Contains live attenuated virus ( all 3 types ) Ideal to give each type as monovalent vaccine Administrative purpose trivalent vaccine given Vaccine contains – 3 lakh TCID 50 of type 1, 1 lakh TCID 50 of type 2 & 3 lakh TCID 50 of type 3 (TCID – Tissue culture infective dose)

49. DIFF. BETWEEN IPV & OPV IPV ( Salk ) Killed , IM, strict Cold chain not req Systemic immunity Doesn’t protect gut – Re- inf. With wild virus Not useful – to control epidemics / Eradication Trained person req. Imm. Shorter – 5 years No vaccine associated paralysis OPV ( Sabin ) Live attenuated Oral, strict Cold chain req. Local & Systemic imm. Protects gut from re inf. With wild virus Useful – Control epidemics / Eradication Trained person not req Immunity – Lifelong Vaccine associated paralysis can occur

50. NATIONAL IMMUNIZATION SCHEDULE Soon after birth – Zero dose polio 1 st dose – 6 weeks 2 nd dose 10 weeks 3 rd dose 14 weeks 1 st booster 18 months 2 nd booster – 4 years 6 months - 5 years Dose – 2 drops Vaccine associated paralytic polio esp with type 3 virus due to mutation

51. REASON FOR VACCINE FAILURE Incomplete schedule Use of date expired vaccine Instability of vaccine Lack of cold chain maintenance – Vaccine vial monitor - Vaccine associated paralytic polio

52. VACCINE VIAL MONITOR

53. ERADICATION OF POLIOMYELITIS A country is said to be free from polio – Zero incidence for continuous 3 years Why eradicate polio ? Humans – only reservoir No chronic carrier state Half life – excreted wild polio virus in sewage – 48 hours Potent vaccine is available Lifelong immunity if schedule is completed correctly

54. CONTD….. Last case in United States in 1979 Western Hemisphere certified polio free in 1994 Last isolate of type 2 poliovirus in India in October 1999 Global eradication goal

55. STRATEGIES OF POLIO ERADICATION High level routine immunization coverage Pulse polio immunization Acute flaccid paralysis surveillance Mop up immunization

56. PULSE POLIO IMMUNIZATION GOI – introduced 1995 Supplementary programme – Routine imm. PPI started - in-spite of good routine immunization coverage, because 10 % remained unimmunized For 100 % Immunization coverage < 3 yrs Later on it was extended to < 5 yrs children PPI on NID on 2 occasions with 4-6 weeks gap

57. HOW PPI HELPS TO ERADICATE POLIO W i ld po l io v i r u s r e qui r es u n im m uni z ed gut f o r its multiplication within 1-2 days of its excretion Imm u n i z ed c hil d r en ’ s gut do es n’ t al lo w multiplication of wild polio virus Hence if all children < 5years get immunized against polio, on PPI day, wild polio virus can’t survive

58. AFP SURVEILLANCE Introduced– 1997 in India To detect final reservoir of wild polio virus AFP– Sudden onset of paralysis of the limb <4 weeks duration in child <15 years AFP surveillance– Detecting all cases of acute paralysis not only polio cases, it ensures that polio cases are not missed Hence AFP surveillance is tool to detect suspected polio cases

59. OBJECTIVES OF AFP SURVEILLANCE To detect high risk areas – to plan immunization To monitor progress of AFP cases To certify country polio free I t i s an i n d i cat o r of se n siti v ity of su r v e i l l a n ce system

60. EVENTS AFTER DETECTING AFP CASE (60 days F ollow U p ) AFP case – 2 stool s am ples W il d P olio virus C onfi r med case No wild polio virus Discard Inadequate sample Residual w eakne s s Died, Lost - FU C onfi r m No residual weakness Discard

61. REPORTING OF AFP CASES All A F P cases r e p o r t ed t o Di s tr i ct im m uni z a tion officer – DIO, as early as possible In case no AFP cases- Zero reporting is must Initial phase AFP required – detecting polio virus Later stages – to prove the absence of polio virus AFP – Public health emergency

62. LINE LISTING OF CASES Reporting of every case of AFP in a prescribed proforma It includes – Name, age, sex, address, imm. Status, date of onset of paralysis, clinical findings etc Helps in avoiding duplication of case Follow up of the case Identify high risk areas Implement control measures

63. MOP UP IMMUNIZATION Last stage in polio eradication Door to door immunization of all children in high risk area – circulation of wild polio virus is reported or suspected All children within 5 km area immunized About 2000- 3000 children are immunized Started within 48 hrs of reporting a case of AFP and to complete within 7 days

64. INTENSIVE PULSE POLIO IMMUNIZATION- IPPI In- spite of PPI, AFP cases do occur GOI – 1999 intensified PPI 3 days programme 1 st day – Children immunized in Booth 2 nd day – House to house survey X mark if child not immunized, non co-operation, locked houses P mark if child is immunized ( GV mark on the finger of the child indicate immunization )

65. CONTD….. 3 rd day – Only X marked houses are visited Children are immunized with OPV X mark is wiped P mark is put on the door Purpose of IPPI – not to miss even single child

66. SUPPLEMENTARY IMMUNIZATION ACTIVITIES- SNID In some states – UP , Bihar To supplement PPI, 2 more round of OPV from October - January Better coverage of children Consistency in vaccine coverage To maintain high level of AFP surveillance