2. Picornaviridae Assistant Professor & Consultant Virologist College of Medicine & KKUH By: Dr.Malak El-Hazmi

3. Picornaviruses Nonenveloped, icosahedral, ss (+) RNA

4. Enterovirus Members of the Family Picornaviridae Genus Species Poliovirus Coxsackieviruses Echoviruses Enteroviruses ( 68-71) Hepatovirus Parechovirus Rhinovirus Kobuvirus Cardiovirus Aphthovirus Erbovirus Teschovirus

5. Characteristics of Human Picornaviruses Property RhinoVs Enteroviruses ParechoVs Polio Coxsackie A B EchoEntero Serotypes >1001-3 1-241-6 1-3468 -711-4 Acid pH (3.0) LabileStable Temp 33 o C37 o C Site NoseGIT

6. Usual Host range of human enteroviruses: animal and tissue culture spectrum a a Many enteroviral strains have been isolated that do not conform to these categories b New types, beginning with type 68, are now assigned enterovirus type numbers instead of coxsackievirus or echovirus numbers. Types 68-71 have been identified. C Type 23 has been found to be the same as echovirus 9. d Echovirus 8 was determined to be the same serotype as echovirus 1 ; echovirus 10 has been reclassified as a reovirus type 1, echoviruses 22 & 23 as parechoviruses types 1& 2, echovirus 28 as human rhinovirus 1 A, and echovirus 34 as coxsackievirus A24. Cytopathic effect Illness & Pathology Virus Antigenic types b Monkey Kidney tissue culture Human Tissue culture Suckling Monkey mouse Polioviruses 1-3++-+ Coxsackieviruses, gp A 1-24 c ±± (+) flaccid - Coxsackieviruses, gp B 1-6++ (+) spastic - Echoviruses 1-34 d +±-- Enteroviruses 68-71++--

7.   Reservoir : Human   Spread :   Fecal - oral route (mainly)   Inhalation of Infectious aerosols   Direct & indirect contact of eye secretions (Crowded, Poor hygiene & Sanitation)   Age : children > adults   Seasonal distribution: summer & fall Epidemiology Excreta from human HandSewage Solid waste landfills Water Supply Shellfish Man

8. Pathogenesis Echo,cox HFM Most EVs are cytolytic, some cause immunopath mech

9. Coxsackievirus SyndromePoliovirus Types 1-3 Group A Types 1-24 Group B Types 1-6 Echovirus Types 1-34 Enterovirus Types 68-71 Neurologic Aseptic meningitis Paralysis Encephalitis 1-3 Many 7,9 2,5-7,9 1-6 2-5 1-5 Many 2,4,6,9,11,30 2,6,9,19 71 70,71 Skin and mucosa Herpangina Hand-foot-and-mouth disease Exanthems 2-6,8,10 5,10,16 Many52,4,6,9,11,16,18 71 Cardiac and muscular Pleurodynia (epidemic myalgia) Myocarditis, pericarditis 1-5 1,6,9 1,6,9,19 Ocular Acute hemorrhagic conjunctivitis2470 Respiratory Colds Pneumonia Pneumonitis of infants Pulmonary edema 21,24 9,16 1,3,4,5 4,5 4,9,11,20,25 68 71 Gastrointestinal Diarrhea Hepatitis 18,20-22,24 2 4,95 Many 2 4,9 Other Undiff. Febrile illness Generalized disease of infants Diabetes mellitus 1-3 1-6 1-5 3,4 11 Human enteroviruses & commonly associated clinical syndromes. 1 1 Examples are not all-inclusive. Other enterovirus types may be associated with a given disease: 2 Causality not established

10. Herpangina

11. Hand, Foot & Mouth disease

12. Coxsackievirus SyndromePoliovirus Types 1-3 Group A Types 1-24 Group B Types 1-6 Echovirus Types 1-34 Enterovirus Types 68-71 Neurologic Aseptic meningitis Paralysis Encephalitis 1-3 Many 7,9 2,5-7,9 1-6 2-5 1-5 Many 2,4,6,9,11,30 2,6,9,19 71 70,71 Skin and mucosa Herpangina Hand-foot-and-mouth disease Exanthems 2-6,8,10 5,10,16 Many52,4,6,9,11,16,18 71 Cardiac and muscular Pleurodynia (epidemic myalgia) Myocarditis, pericarditis 1-5 1,6,9 1,6,9,19 Ocular Acute hemorrhagic conjunctivitis2470 Respiratory Colds Pneumonia Pneumonitis of infants Pulmonary edema 21,24 9,16 1,3,4,5 4,5 4,9,11,20,25 68 71 Gastrointestinal Diarrhea Hepatitis 18,20-22,24 2 4,95 Many 2 4,9 Other Undiff. Febrile illness Generalized disease of infants Diabetes mellitus 1-3 1-6 1-5 3,4 11 Human enteroviruses & commonly associated clinical syndromes. 1 1 Examples are not all-inclusive. Other enterovirus types may be associated with a given disease: 2 Causality not established

13.   Pathway to CNS by:   Blood   Peripheral nerves   Causing destruction of motor neurons of AHCs   Rarely affects brain stem (bulber poliomyelitis ) Pathogenesis of polio:

14. Pathogenesis of Polio : Immunity : IgA & IgG = Lifelong type-specific immunity

15. Poliovirus Infections Minor Illness No illness Major Illness 1- Nonparalytic poliomyelitis (Aseptic meningitis) 2- Paralytic poliomyelitis: (Flaccid paralysis) Abortive poliomyelitis (No CNS involvement) 90-95% Asymptomatic 4-8% 1-2%

17. Poliovirus Infections :   Bulber poliomyelitis ( brain stem)   Post polio syndrome

18. Lab Diagnosis of Enteroviruses   Virus isolation: Samples: Stool (best).Rectal, throat swabs, conjunctival swab, CSF Inoculate in MKC & HDF All EVs grown except some strains of Cox A viruses Observe for CPE Identify the type by Neutralization Test   CSF in aseptic meningitis; lymphocytosis Glucose level N to slightly, Protein level N or slightly Isolation rate is variable EV RNA detected in CSF by RT-PCR   Serology (limited value) IgM ≥ 4 fold rise in AB titer b/t Acute & Convalescent sera

19. Management   Rx:   No antiviral Rx   Prevention:   Sanitation & Hygienic measures   Poliovirus vaccines a- Inactivated polio vaccine (IPV) (Salk, Killed) (S/C or IM) b- Live-attenuated polio vaccine (OPV) (Sabin, oral)

20. Important Features of Polio Vaccines Attribute Killed (IPV)Live (OPV) 3 types(trivalent) YesYes Prevents disease YesYes Route of administration Injection Oral Induces humoral IgG YesYes Induces intestinal IgA NoYes Interrupts transmission NoYes Affords 2 o protection by spread to others Causes disease in the immun ed NoYes Reverts to virulance No Yes (rarely) NoYes Co-infection with other EVs may impair immunization Requires refrigeration NoYes Duration of immunity Shorter Longer

21. Poliovirus Vaccine   Adverse reactions ;   local reactions (IPV)   Vaccine -Associated Paralytic Poliomyelitis (OPV) adult, immuno ed   4 doses of PV; 2, 4, 6-18 ms & 4 - 6 yrs   Pediarix contains IPV, DTaP & HB vaccines

22. Polio Vaccination of Adults   Indications:   Travelers to polio-endemic countries   Selected laboratory workers   HCWs   IPV; 0, 1-2 ms, 6-12 ms

24. عن معاذ بن جبل رضي الله تعالى عنه أن رسول ا لله صلى الله عليه وسلم قال { ألا أدلكم على أبواب الخير } قلت : نعم قال :{ الصوم جنة, والصدقة برهان, وقيام العبد في جوف الليل يطفئ كل خطيئه }