1. Paramyxoviruses 미생물학교실 권 형 주

2. GenusHuman Pathogen Mobillivirus Measles virus (rubeola, 홍역 – maculopapular rash) Paramyxovirus Parainfluenza viruses 1 to 4 Mumps virus Pneumovirus Respiratory syncytial virus –upper respiratory tract infection Metapneumovirus - Cell-cell fusion Syncytia formation Multinucleated giant cells - New group Zoonosis-causing viruses Nipah virus Hendra virus - Live vaccine Measles viruses Mumps viruses  only one serotype Paramyxoviruses (from Greek para-, beyond, -myxo-, mucus or slime, plus virus, from Latin poison, slime)

3. STRUCTURE and REPLICATION - Negative-sense, single-stranded RNA - Envelope -the order of the protein-coding regions differs for each genus - orthomyxoviruses : segmented genome

5. Replication of paramyxoviruses

6. Measles Virus ( 홍역바이러스 ) - Measles is still one of the most prominent causes of disease (45 million cases per year) and death (1 to 2 million per year) worldwide in unvaccinated populations Pathogenesis and Immunity Family : Paramyxoviridae Genus : Mobillivirus - Host – only human - cell fusion, giant cells - cell-to-cell spread  escape antibody control - Hemagglutinin(+), Neuraminidase (-) - Highly contagious - respiratory droplets

7. - Time course of measles virus infection. - 초기증상 : cough, conjunctivitis, coryza, and photophobia (CCC and P) - Koplik’s spots, rash - SSPE (subacute sclerosing panencephalitis, 아급성 경화범뇌염 )-rare -Maculopapular measles rash : T cells targeted to measles-infected endothelial cells lining small blood vessels  rash (lifelong immunity) - Encephalitis 1) direct infection of neurons 2) a postinfectious encephalitis : immune mediated 3) SSPE – a defective variant of measles

8. Epidemiology -Development of effective vaccine programs

9. Clinical Syndromes -Incubation periods : 7-13 days - 초기증상 ( 발진전 ) : High fever, CCC and p -After 2 days of illness : Koplik spots - A typical mucous membrane lesions - first day or two after the rash appears - mouth, conjunctivae, vagina - 발진 (exanthem of measles) : starts belows the ears and spreads over the body : maculopapular rash - Complications : Pneumonia, bacterial superinfection Prevention

10. Parainfluenza Virus -Respiratory viruses : mild cold-like symptoms, serious respiratory tract disease - Human pathogens : four serotypes

11. Clinical Syndromes -Types 1, 2, 3 : respiratory tract syndromes - mild cold-like upper respiratory tract infection (coryza, pharyngitis, mild bronchitis, wheezing, fever) - Bronchiolitis - Pneumonia - Croup (laryngotracheobronchitis) Laboratory Diagnosis -Isolated from nasal washing and respiratory secretion -Grow well in primary monkey kidney cells -Hemagglutination -Serotype (antibody) ; hemagglutination inhibition -RT-PCR -Administration of nebulized cold or hot steam -No specific antiviral agents -Killed vaccine : ineffective -No live attenuated vaccine Treatment, Prevention, and Control

12. Mumps Virus - 볼거리, 볼치기 ( 귀밑샘염 ) - Parotitis ( 이하선염 ) : painful swelling of the salivary glands - Isolated in embryonated eggs in 1945 - Cell culture in 1955 - Human pathogen : One serotype

13. -Recovered from saliva, urine, pharynx, stensen duct, cerebrospinal fluid - Grow well in monkey kidney cells - Formation of multinucleated giant cells -Hemadsorption of guinea pig erythrocytes: hemagglutinin -MMR vaccine -Antiviral agents are not available

14. Respiratory Syncytial Virus (RSV) 호흡기세포융합바이러스 Family : Paramyxoviridae Genus : Pneumovirus Subgroups : A and B - Fatal acute respiratory tract infection - Infants, young children

15. RSV Virion, Genome and Proteins plasma membrane budding virion (EM by Tony Kalica, LID/NIAID) 150 nm NS2 NS1 M2-1 M2-2 Single-stranded negative-sense RNA, 15.2 kb 3´5´ G F SH M N P L ribonucleocapsid envelope spikes nonstructural NS1 NS2 inhibit host type I interferon response regulation of RNA synthesis M2-2 unassigned inner envelope face assembly M M2-1 transcription processivity factor RNA-binding phosphoprotein polymerase N P L Neutralization targets SH G attachment fusion unknown F

16. RSV –syncytium formation

17. - Virus infections almost always occur in the winter. - Infants : lower respiratory infection (bronchiolitis and pneumonia) - Children : mild to pneumonia - Adults : mild symptoms Symptom : bronchiolitis, pneumonia, mechanical ventilation, and respiratory failure in infants.

19. Laboratory Diagnosis Treatment, Prevention, and Control -RT-PCR -Immunofluorescence and enzyme immunoassay test -Ribavirin ( 제한적 ) : inhalation(nebulization) -Passive immunization :anti-RSV Ig ( 제한적 ) -No vaccine is currently available -Inactivated vaccine : severe RSV disease : heightened immunologic response (Th2 immune response ?)