Viral Respiratory Tract Infection-Part 2 Prof. Dr Asem Shehabi Faculty of Medicine, University of Jordan

Rhinoviruses Rhinoviruses part Picorna virus Group.. have positive- sense single stranded RNA genomes..surrounded by protein capsid composed 4 viral protein (VP1-4).. Icosahedron structure without Envelop. A & B Rhinovirus major group .. Over 100 serotypes.. Susceptible to stomach acidity, infect nasal mucosa..Common incidence all year seasons.. Few common serotypes are highly human communicable .. droplet infection.. Upper Respiratory Tract.. Caused about 10-20% of common cold infections/mild Flu-like symptoms.. Epidemic Outbreaks in crowded meeting & areas.

2/ Incub. 2-3 days.. Mild /Severe .. Acute Inflammation Nasal & Throat mucosa.. Mild sore throat, watery nasal discharge, cough.. Children often develop sinusitis, otitis media.. Serotype–specific Immunity for short time.. Re-infection is common.. Rare Lower RT infection. Complications: Bacterial infections.. Sinusitis, Pneumonia (Pneumococcus, H.influenzae, S.aureus)..antibiotic treatment. No vaccine

Corona Respiratory Viruses Virus structure: have positive- sense single stranded RNA genomes, Lipoprotein envelop associated with characteristic ring of small protein structures (spikes) covers nucleocapsid.. Crown-like structures..Multiply within cell cytoplasm..causing cell lysis & syncytia rapidly. Causing up 30% of human common cold. Attached to Ciliary epithelium Trachea, Nasal mucosa.. Mostly mild URT Infections. Both symptomatic or asymptomatic.. Winter-Spring.. Major symptoms Nasal discharge.. less pharyngitis, Fever or Cough.. Affect All Ages. Re-infections is common.. Mostly Sporadic Cases..less outbreaks.. In animals-birds (chicken) infect both Gut & RT.. May affects liver and CNS.

Coronavirus

SARS-Coronavirus SARS ( Severe Acute Respiratory Syndrome) is caused by Corona related virus. First detected 2003 in China.. Later spread worldwide (2003-4) within weeks first in Asian..later numerous countries caused thousands cases & hundred Deaths. In 2012-14 New SARS-Like Coronavirus strain caused Middle East Respiratory Syndrome.. More fatal cases, Saudi-Arabia, Jordan , other countries Coronaviruses affect the upper respiratory & gastrointestinal tract human ,animal & birds. Clinical Infection cause suddenly severe mixed viral & bacterial pneumonia.. Symptoms include high fever, dry cough, dyspnea, headache, hypoxemia, high mortality ..more severe in middle ages & elderly persons.. progressive respiratory failure & liver damage..few days..No vaccine or specific antiviral therapy.

Rubellavirus-1 Rubivirus: Rubella/ German measles.. positive-ss RNA, Envelope ..carries only Haemaggultinins (2 glycoproteins, E1, E2), only one virus antigenic type.. Part of Togavirus /Arovirrus Rubella is a highly contagious viral disease, spread through contact with droplet discharges nose, throat, rarely by skin contact.. Susceptible ultraviolet light, low pH, heat. The virus may also be present during active disease in the urine, feces, skin   Rubella virus incubation 2 weeks in Respiratory tract mucosa.. Saliva, Lymphadenopathy, Viremia, Mild fever, later macular fine skin rash .. develops on face, neck.. then the trunk and extremities.. Mostly subclinical infection.. Not recognized.. more in Children than Adults.. Results Rubella antibodies & immunity.

Rubella Rash

Rubellavirus-2 Rubella may have symptoms similar to those of flu.. Lymphadenopathy begins 3 days prior to the skin rash and lasts until 3 days after disappear of rash.. Infected person remain for 2 weeks highly Infectious to susceptible persons of all ages. Humans are the only known reservoir for disease.. RT, Intestine, Urinary tract. Rubella infection spread all the year.. But more in late winter and spring months. Rubella is mostly endemic in countries who have less than 90% immunization. Infection during pregnancy: Lack of Rubella antibodies.. Virus reach placenta & fetus via blood.. multiply in fetal organ and cause severe damage, stillbirth, abortion during the 1-trimester (3-4 months)

Rubellavirus -3 Risk of birth defects drops after the first trimester/20- week pregnancy.. rarely any complications in fetus. Rubella Intra-uterine infection during pregnancy: Detected by presence virus IgM antibodies in fetus blood.. Mother should abort her fetus. Congenital rubella syndrome: Affects the eyes of new born babies (cataracts), Blindness, congenital heart defects, Brain & CNS abnormalities, Mental retardation, Deafness, Hepatitis. Virus may persist in the infected new born baby tissues for 3-4 years and can infect others up to one year after birth. Rubella infection acquired later in life of young women may be associated with Arthralgia / Arthritis.

Rubella immunity-4 Rubella Humoral antibodies develop soon after infection/vaccination (IgM, IgG).. Rubella IgG alone indicates immunity .. The lack of both antibodies or IgG indicates susceptible to Rubella. Passive prophylaxis: Susceptible pregnant women after contact with infected Rubella case should given Rubella human immunoglobulin. Laboratory test : A 4-fold increase in Rubella serum antibodies titer IgM or both IgG & IgM is diagnostic for recent infection. A live attenuated vaccine is given in combination with measles and mumps (MMR) to any woman lacks enough Rubella Antibodies.. 2-3 months prior to becoming pregnant.

Adenoviruses Group Virus structure: linear ds-DNA, non-enveloped, enclosed in a cubical capsid shell with projected surface fibers act as specific receptors.. human & Avian specific virus groups.. Wide distribution nature. Human Adenovirus: 47 serotypes..common few types Pathogensis: Attachment to mucosal surfaces of respiratory tract, GI tract, and conjunctiva.. Produces severe cytopathic effect (CPE) in infected tissues. Transmission: Respiratory droplets, Saliva, Blood., Fecal-oral, Urine..close contacts.. common asymptomatic infections in medical professionals, Common healthy carriers.. children & Adults can transmitted the virus. Virus persist in Tonsils+ Adenoids, Intestine & Urinary tract , in lymphoid tissues including Peyer's Patches.. For short/ long live time.. may be reactivated by immunosuppression condition.

Adenoviruses (ds-DNA) Adenoviruses (ds-DNA).. non-enveloped, The capsid is built up 252 capsomers with apical Surface Fibers

Adenovirus-2 Clinical Manifestation: Almost all humans acquire Adenovirus infection early in life.. Only a few percentage (1- 5%) develop mild clinical disease.. Serious disease in Immunocompromised persons, Common associated with kidney transplant. Common Clinical Diseases: 1-Acute Respiratory Infections: Few serotypes.. Common in crowded schools, military & refuge camps .. Acute febrile pharyngitis, fever, runny nose, mild cough.. Rarely pneumonia/ Pharyngo-conjunctivitis. 2-Conjunctivitis: Epidemic keratoconjunctivitis with no systemic symptoms, very painful, Sporadic & Outbreaks cases. 3-Acute Gastroenteritis: Few serotypes.. common infants.. Less other children/Adults.. Mesenteric Adenitis.. Mild-acute Diarrhea.. chronic diarrhea in patient with AIDS or immunosuppressed conditions.

Adenovirus-3 4-Acute Hemorrhagic Cystitis: Children & Young Males/Females.. Infection genital tract cause Cervicitis , Urethritis , Haemorrhagic cystitis, Hepatitis, Pneumonitis..Fatal immunosuppressant. Immunity: Specific humoral antibodies against one or few serotype..Last long time and protect against re-infection.. Each country has endemic specific Adenovirus type infections. Diagnosis: Detection a rise in specific antibodies by ELASA.. Viral antigen Detection DNA PCR . Treatment: Antiviral drugs for eye infection & other patients .. Cidofovir, Ribavirin.. No Vaccine.