| Question | Answer |
| Important viral causes of LRTI: | Influenza
Para-influenza
Respiratory syncytial virus
SARS
MERS
Human metapneumovirus (2001) common in comprised children and elderly persons |
| Para influenza Viruses cause: | Croup (Acute Laryngotracheobronchitis),pneumonia in children, and common cold – like disease in adults |
| 5 subtypes for Para Influenza viruses: | 1, 2, 3, 4a and 4b |
| Surface spikes on para influenza viruses consist of: | H, N and fusion proteins |
| Transmission of Parainfluenza via: | Respiratory droplets |
| Clinical findings of infection with parainfluenza: | Croup
– Harsh cough
– Inspiratory stridor
– Hoarse voice
Patients are usually afebrile.
About 80% of patients exhibit runny nose |
| Which other viruses can induce croup? | Influenza viruses
RSV
Measles and chickenpox |
| Lab diagnosis: | Clinically for croup
Cell culture isolation
Immunoflurescence
Antibody rising titre using HAI or ELISA |
| Treatment for parainfluenza: | Nursing in plastic tents supplied with cool, moistened
oxygen
Severe respiratory obstruction may require endotracheal intubation followed by a tracheotomy |
| RSV infections cause: | Pneumonia
Bronchiolitis in infants |
| RSV is a major nosocomial pathogen in: | Pediatric wards |
| Transmission of RSV | Respiratory droplets and direct contact of contaminated hands with the nose or eye |
| Incubation period is: | 3-6 days |
| Syncytia form in which organ, in the case of RSV? | The lungs |
| RSV is the most common cause of: | Severe lower respiratory disease in young infants
50-90% bronchiolitis
5-40% pneumonias |
| In young children, RSV may cause: | Otitis media |
| In older children and adults, RSV may cause: | Common cold like disease |
| What is the effect of RSV infections in infants? | Febrile URTI
Lower respiratory tract involvement
Worsening cough
Tachypnoea and dyspnoea
Hyperinflation of lungs
Cyanosis |
| Risk groups for RSV infections: | Infants with congenital heart disease
Infants with pulmonary disease
Immunocompromised infants
Nephrotic syndrome and cystic fibrosis |
| Complications of RSV infections: | 1) Apnea
2) Alterations in pulmonary functions which may lead to chronic lung diseases later in life |
| Laboratory diagnosis of RSV infection is done with: | Immunoflurescence on smears of respiratory secretions
ELISA for detection of RSV antigens
Isolation in cell culture (multinucleated giant cells or syncytia)
Rise of antibody titer |
| Characteristics of SARS-causing virus: | Enveloped virus, Replicates in cytoplasm of animal cells
Single-strand 30 kb RNA genome
First identified in Guangdong Province, China in 2002
Associated Coronavirus SARS-HCoV
Replication in cytoplasm rather than nuclei |
| Symptoms for SARS: | Initially: High fever of 38оC or higher, head and body aches, and malaise.
Week Later: dry cough, difficulty breathing and severe diarrhea.
Recovery: after 5 to 6 days |
| Diagnostic tests for SARS: | Antivirals and steroids used for atypical pneumonia
Lab tests:
RT-PCR
EIA
ELISA |
| Prevention: | Isolation
Sterilization of area
3 possible Vaccines (whole-killed, adenovirus vector, or recombination spike protein |
| What is MERS? | Middle East respiratory syndrome coronavirus |
| MERS was first reported in: | Saudi Arabia |
| Characteristics of MERS: | Positive-sense, single-stranded RNA virus of the genus Betacoronavirus |
| MERS-CoV is distinct from | SARS coronavirus
Common-cold coronavirus
Betacoronaviruses (HCoV-OC43 and HCoV-HKU1) |
| How does transmission of MERS occur? | Via respiratory secretions |
| Metapneumovirus was first isolated in: | Nasophargyngeal aspirates from 28 children over a 20 year period |
