RNA viruses

RNA VIRUSES

Orthomyxoviruses Epidemic influenza A , B , C Due to Antigenic drift ( minor changes of HA ) Pandermic Antigenic shift ( major changes of HA ) influenza Sings : fever , sorethroat , headache , cough , nasal congestion & Resp. infection Transmission : aerosol Treatment & prevention :; Antiviral (Amantidine) Vaccination : Difficult due to Ag changes

RNA Viruses: Orthomyxo (influenza)

H&E of Trachea


Paramyxoviruses Parainfluenza human Resp. disease affect young adult & infant ( laryngeotrachitis )“ croup “ ; brocheolitis & pneumoniaTransmission : droplet Mumps : common childhood parotitis one or both side are affected . MMR vaccine solid immunity Measles : infectious disease of childhood ; rash , virus enters Resp. tract regional LN viraemia “ prodromal stage “ conjuctivitis , nasal discharge & fever .Sorethroat “ Koplik’s Spots “ Bluish white spots on buccal mucosa opposite molar teeth then Rash ( reactivation of virus & immuno system ) Koplik spots disappear

Parainflenza (Mumps)

Mumps

Parotid papilla

Suppurative parotid papilla

Parotitis

Parotid papilla

Suppurative parotid papilla

Parainflenza: Measles

Kolplik`s spots

Koplick`s spots & exanthems

Parotid papilla

Suppurative parotid papilla

Parainflenza: Measles

Kolplik`s spots

Koplick`s spots & exanthems

Measles rash

rash

Rash


Complications of measeles Resp. complication ; broncho pneumonia Otitis media Neurological - encephalomyelitis - SSPE progressive degenerative disease of brain Gangrenous stomatitis & noma African child suffer from bad nutrition with ANVG

Destruction of orofacial tissue Transmission of measles : Resp. secretion & urine ( prodromal stage ) Prevention : MMR Respiratory Syncytial virus ( RSV ) Lower resp. infection of infants & young adults

Cancrum oris

Picronaviruses A: Entero viruses Polioviruses : poliomyelitisIngestion of contaminated food ( primary replication in oropharyngeal & intestinal mucosa ) mesenteric LN viraemia CNSCoxsackieviruses : ( genra A , B ) cause mild disease Herpangina : common in children Sorethroat , ulceration an tonsil , soft palate grayish white vesicles on posterior hard palate , self limiting disease Hand , Foot & mouth disease :Coxa A , common in children Oral bright red macules vesides pale center on hand & footTransmission : oral – fecal , nasal route .

Picorna viruses:(ECHO rash)

Coxsackievirus (Herpangina Vs HSV)

Hand, food & mouth disease

HFM

HFM, HSV, GC

B: Rhino viruses : Common cold upper resp. ; more than 100 group transmitted by inhalation ( Winter & Autumn ) Togaviruses Rubella : German measles , childhood disease similar to measles but milder . Untreated during pregnancy lead to congenital abnormality spread by nasal secretion prevention : MMR

Rubella in T.C

Postnatal Rubella



Post and congenital Rubella

Congenital Glaucoma

Congenital cataract


Other RNA viruses Arena Bunya Rota Corona saris Rhabdo Rabies Viruses & Cancers Papova HPV , SV40 cervical carcinoma Adeno animalsHerpes HSV-2 , EBV , HHV-8 –KaposiHepatitis HBV & HCV hepatocellular carcinomaRetro HTLVs ( AIDS )