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Picornavirus Pico + RNA = Picorna

Picornavirus Pico + RNA = Picorna. eIF4G cleaved  cellular protein synthesis is shut off. Kozak sequence (NNNPuNN AUG G ) The initiation AUG codon in the polio virus open reading frame is preceded by eight other AUGs. RCCAUGG RYYAUGG (R = purine, Y = pyrimidine);. Poliovirus infection.

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Picornavirus Pico + RNA = Picorna

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  1. Picornavirus Pico + RNA = Picorna

  2. eIF4G cleaved  cellular protein synthesis is shut off

  3. Kozak sequence (NNNPuNNAUGG ) The initiation AUG codon in the polio virus open reading frame is preceded by eight other AUGs. RCCAUGG RYYAUGG (R = purine, Y = pyrimidine);

  4. Poliovirus infection • Asymptomatic illness results if the viral infection is limited to the oropharynx and the gut. At least 90% of poliovirus infections are asymptomatic. • Abortive poliomyelitis, the minor illness, is a nonspecific febrile illness occurring in approximately 5% of infected people. Fever, headache, malaise, sore throat, and vomiting occur in such people within 3 to 4 days of exposure. • Nonparalytic poliomyelitis or aseptic meningitis occurs in 1% to 2% of patients with poliovirus infections. In this disease, the virus progresses into the central nervous system and the meninges, causing back pain and muscle spasms in addition to the symptoms of the minor illness.

  5. Paralytic polio, the major illness, occurs in 0.1% to 2.0% of persons with poliovirus infections and is the most severe outcome. It appears 3 to 4 days after the minor illness has subsided, thereby producing a biphasic illness. In this disease, the virus spreads from the blood to the anterior horn cells of the spinal cord and to the motor cortex of the brain. The severity of paralysis is determined by the extent of the neuronal infection and by which neurons are affected. Spinal paralysis may involve one or more limbs, whereas bulbar (cranial) paralysis may involve a combination of cranial nerves and even the medullary respiratory center. • Paralytic poliomyelitis is characterized by an asymmetrical flaccid paralysis with no sensory loss. Poliovirus type 1 is responsible for 85% of the cases of paralytic polio. Reversion of the attenuated vaccine virus types 2 and 3 to virulence can cause vaccine-associated disease.

  6. Coxsackievirus and Echovirus Infections

  7. Herpangina Type A 1-10 Type B 1-5 Echoviruses Mostly in children; epidemicin summer months Abrupt fever, sore throat, anorexia, abdominal pain and vesicles on soft palate, pharinx and tonsills

  8. Hand-foot-and-mouth disease • Coxsackie A16, 4, 5, 10

  9. Myocardial and pericardial infections • Coxsackie B, echovirus • Sudden onset Diabetes: Coxsackie B 4

  10. Viral (aseptic) meningitis • Coxsackie A, B • Echovirus • Summer and fall

  11. Fever, rash, and common coldlike symptoms • Summer minor illnes: Rubelliform rush on face, neck and chest Accompanied by fever No distinctive feature Short duration

  12. Plerodynia • Coxsackie B • Sudden chest pain, fever, malaise • (Abdominal or testicular pain)

  13. Laboratory Diagnosis • CSF findings • Culture • Molecular and serological methods

  14. Treatment and Prevention • Vaccine available only for Polio

  15. Rhinoviruses • Epidemiology of Rhinovirus Infections • Disease/Viral Factors • Virion is resistant to drying and detergents • Multiple serotypes preclude prior immunity • Replication occurs at optimum temperature of 33° C and cooler temperatures • Transmission • Direct contact via infected hands and fomites • Inhalation of infectious droplets • Who Is at Risk? • People of all ages • Geography/Season • Virus found worldwide • Disease more common in early autumn and late spring • Modes of Control • Washing hands and disinfecting contaminated objects help prevent spread

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