1. Poliomyelitis The Virus and the disease

9. What is Polio? Introduction Poliomyelitis (polio) is a highly infectious disease caused by a virus. It invade the nervous system, and can cause total paralysis in a matter of hours. It can strike at any age, but affects mainly children under three (over 50% of all cases). The virus enters the body through the mouth and multiplies in the intestine. Initial symptoms are fever, fatigue, headache, vomiting, stiffness in the neck and pain in the limbs.

10. What is Polio? Cont… Amongst those paralyzed, 5%-10% die when their breathing muscles become immobilized. Visible sign of polio infection: fewer than 1% of polio infections ever result in paralysis. Poliovirus can spread widely before cases of paralysis are seen. As most people infected with poliovirus have no signs of illness, they are never aware they have been infected. After initial infection with poliovirus, the virus is shed intermittently in faeces (excrement) for several weeks. During that time, polio can spread rapidly through the community.

11. Poliomyelitis Etiology: poliovirus Family: picorna viridae Polio Virus is sensitive to heat, formaldehyde ultraviolet light, chlorine First described by Michael Underwood in 1789 Enterovirus (RNA)

12. دپولیو ویرس په چاپیریال کښی دژوندی پاتی کیدو موده : دژوندی پاتی کیدو مودهدحرارت درجه په سانتی ګریډ ثانیه SecondOver 50 C څخه زیات دقیقه Minute C40-50 ساعت Hour د 20-40 سانتی ګریډ ورځ Day د 10-20 سانتی ګریډ اونی WEEK د 0-10 سانتی ګریډ میاشت Month د 0 - منفی 10 سانتی ګریډ کال Year دمنفی 10 - منفی 20 سانتی ګرید نا معلوم Unknown دمنفی 20 څخه زیات سانتی ګرید

13. Poliomyelitis Three related enteroviruses Type 1: most typically causes outbreaks most likely to cause paralysis Type 2: easiest to eradicate Type 3: often last to be eradicated

14. Who is most at risk of polio? Polio mainly affects children under five years of age. However, immune and/or partially immune adults and children can still be infected with poliovirus These infected individuals can carry the virus for long enough to take the virus from one country to another, infecting close contacts and contaminating sanitation systems. This could facilitate transmission especially in countries where sanitation systems are sub-standard.

15. How is polio spread? Poliovirus is mainly passed through person-to-person contact. Most people infected with the poliovirus do not develop polio paralysis or other symptoms of polio infection. However 1 in 200 people do have symptoms and can become paralyzed. The virus enters the environment through faeces of people infected then is passed to others especially in situations of poor hygiene. The poliovirus can also infect persons who have been vaccinated and can be carried by them.

16. Epidemiology Reservoir Human Transmission Fecal-oral Oral-oral possible Temporal pattern Summer-fall (temperate) Communicability 7-10 days before onset of paralysis Virus present in stool 3-8 weeks

17. Epidemiology Wide spread all over the world It is a disease of children, more common in males, In Low immunization coverage, unhygienic condition, and over crowded condition

18. Epidemiology Immunity life long, secondary infection is rare New born has transient immunity Nearly all epidemics are due to type 1, whereas types 2 and 3 are more often isolated in vaccine-associated poliomyelitis.

19. Epidemiology Disease of young children -80-90% <5 yrs Seasonal increase in cases in late summer Silent transmission - >99% of cases sub clinical Risk of paralysis increased by tonsillectomy, excercise, pregnancy, IM injections

20. Immunity By immunization Immunity to one type does not protect against other types Passive immunity from mother lasts several weeks in baby Believed to be life long by natural infection or OPV Optimal protection requires 3 or more doses of OP Epidemiology of Poliovirus

22. Pathogenesis Entry into mouth Replication in pharynx, GI tract, local lymphatic Hematologic spread to lymphatics and central nervous system Viral spread along nerve fibers Destruction of motor neurons

23. POLIO PARALYSIS Once established in the intestines, poliovirus can enter the blood stream and invade the central nervous system - spreading along nerve fibres. As it multiplies, the virus destroys nerve cells (motor neurons) which activate muscles. These nerve cells cannot be regenerated and the affected muscles no longer function. The muscles of the legs are affected more often than the arm muscles.

24. POLIO PARALYSIS Cont… The limb becomes floppy and lifeless a condition known as acute flaccid paralysis (AFP). More extensive paralysis, involving the trunk and muscles of the thorax and abdomen, can result in quadriplegia. In the most severe cases (bulbar polio), poliovirus attacks the motor neurons of the brain stem - reducing breathing capacity and causing difficulty in swallowing and speaking. Without respiratory support, bulbar polio can result in death.

25. POLIO: THE HIDDEN VIRUS Poliovirus can spread widely without even being 'seen'. As most people infected with poliovirus have no signs of illness, they are never aware they have been infected. After initial infection with poliovirus, the virus is shed intermittently in faeces (excrement) for several weeks.(3-8 weeks) During that time, polio can spread rapidly through the community.

26. HOW IS POLIO SPREAD? Poliovirus is spread through person-to-person, fecal-oral contact. Where hygiene and sanitation are poor, young children are especially at risk. Young children who are not yet toilet-trained are a ready source of transmission Polio can be spread when food or drink is contaminated by faeces. There is also evidence that flies can passively transfer poliovirus from faeces to food.

27. How is polio spread? Cont… Asymptomatic individuals will not develop polio, but can carry the virus in their intestines and can pass it to others in conditions of sub-standard hygiene. The disease may infect thousands of people, depending on the level of sanitation, before the first case of polio paralysis emerge. Individuals can carry the virus in their intestines just long enough to transmit to others. A single confirmed case of polio paralysis is considered epidemic

28. Risk Factors These include: immune deficiency pregnancy removal of the tonsils (tonsillectomy) intramuscular injections injury

29. Clinical Features of Poliomyelitis Acute onset, flaccid paralysis Fever present at onset No progression after 2-3 days Asymmetric Legs affected most often Mortality rate 5-10% Paralysis is permanent Aseptic meningitis & non-paralytic illness

30. Index symptoms (Clues) - Paralysis, paresis (weakness), - Flaccid (floppy) paralysis (in combination with any other words) - Weakness (of limb, of unclear origin, etc.) - “Gait disturbance", -- “Cannot walk", etc.

31. Clinical Outcome of Poliovirus Infections asymptomatic infection(90-95%) clinical illness, no paralysis(4-8%) paralytic poliomyelitis(< 1%)

32. Diagnosis Clinical: Acute onset of Flaccid paralysis Asymmetric Paralysis Associated fever Affecting leg than arms Decreased tendon reflexes Intact sensation Laboratory Stool culture: Viral Culture for primary isolates (National Labs) Serological test: Antibody testing CSF: Lymhocytosis and elevated proteins and rarely detection of Polio virus PCR amplification, to determine whether it is " wild type or "vaccine type" ( Regional Labs )- Intratypic differentiationPCR wild type Genetic tree : to determine the source of the virus (specialized labs)

33. Supportive Care to Parlayed persons by polio There is no cure for polio.cure Treatment is entirely symptomatic. The focus of modern treatment has been on providing relief of symptoms, speeding recovery and preventing complications. Supportive measures include antibiotics to prevent infections in weakened muscles, antibiotics analgesics for pain,analgesics moderate exercise and a nutritious diet.

34. Treatment of polio often requires long-term rehabilitation, including physical therapy,physical therapy braces, corrective shoes and, orthopedic surgery in some cases,. orthopedic surgery Portable ventilators to support breathing.ventilators Today many polio survivors with permanent respiratory paralysis use modern jacket-type negative-pressure ventilators that are worn over the chest and abdomen.jacket-type Treatment Cont….

35. Prognosis Patients with abortive polio infections recover completely In those that develop only aseptic meningitis, the symptoms can be expected to persist for two to ten days, followed by complete recovery. In cases of spinal polio, if the affected nerve cells are completely destroyed, paralysis will be permanent; Nerve cells that are not destroyed but lose function temporarily may recover within four to six weeks after onset. Spinal polio 50% the patients with recover fully, 25% recover with mild disability and 25% are left with severe disability.

36. Prognosis Cont… 5–10% of patients with paralytic polio die due to the paralysis of muscles used for breathing. 2–5% of children and up to 15–30% of adults die Bulbar polio often causes death if respiratory support is not provided; with support, its mortality rate ranges from 25 to 75%, depending on the age of the patient. When positive pressure ventilators are available, the mortality can be reduced to 15%.

37. Complications Skeletal deformities,Skeletal Tightening of the joints and Movement disability Equines foot deformities of the spine (such as scoliosis)scoliosis one leg is shorter than the other and the person limps and leans to one side Osteoporosis and increased likelihood of bone fractures may occurOsteoporosisbone fractures Extended use of braces or wheelchairs may cause compression neuropathyneuropathy Complications from prolonged immobility involving the lungs, kidneys and heart:lungskidneys heart pulmonary edema, aspiration pneumonia, urinary tract infections, kidney stones, paralytic ileus, myocarditis and pulmonary edemaaspiration pneumoniaurinary tract infections kidney stonesparalytic ileusmyocarditis cor pulmonale.cor pulmonale

38. How can polio be prevented? There is no cure for polio, It can only be prevented through immunization. Polio vaccine, given multiple times, almost always protects a child for life. Full immunization will markedly reduce an individual's risk of developing paralytic polio. Full immunization will protect most people,

40. Polio Eradication Strategies 1- Strong EPI Routine Program OPV 3 Coverage equal or more that 80% 2 -National Immunization days the objective is to vaccinate all the target under five children (100%) 3-AFP Surveillance to reach and on time notify all paralysis or weaknesses under fifteen years old children 4- Mopping Up Immunization 100% reach and vaccinated all under five years old children in the selected area or district with strong monitoring.

44. Polio Vaccines Oral polio vaccine (OPV): Developed in 1952 by Dr Albert Sabin and licensed in 1955Developed in 1952 by Dr Albert Sabin A live attenuated (weakened) vaccine OPV is given orally. An inactivated (killed) polio vaccine (IPV): Developed in 1957 by Dr. Jonas Salk and licensed in 1962Developed in 1957 by Dr. Jonas Salk IPV has to be injected by a trained health worker. IPV works by producing protective antibodies in the blood (serum immunity)

45. OPV Advantages of Oral Polio Vaccine OPV is an orally applicable vaccine. It does not have to be administered by a trained health worker, Can be given by volunteers, Does not require sterile injection equipment. The vaccine is relatively inexpensive ‘Passive' immunization of persons within close contact. The unique ability of OPV to induce intestinal local immunity.

46. Disadvantages of Oral Polio Vaccine Vaccine Associated Paralytic Poliomyelitis: (VAPP) Extremely rare cases (approx. 1 in every 2.5 million doses of the vaccine) Relatively more common with the first dose Vaccine-derived polioviruses (VDPV): Genetically mutant strain of OPV Common in a community with low population immunity

47. INACTIVATED POLIO VACCINE (IPV) Advantages of inactivated Polio Vaccine IPV is not a 'live' vaccine - no risk of vaccine- associated polio paralysis. Immunization with IPV triggers an excellent response of the immune system in most IPV recipients.

49. د پولیو د منځه وړلو نوښت د افغانستان داسلامی دولت ولسمشر دپولیو دامحا پروګرم ته په نړیواله کچه ژمن دی

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