Table 46.1.
Viruses infecting the respiratory tract
| Virus | No. of serotypes | Group antigen? | Common disease presentationa |
|---|---|---|---|
| A. USUALLY PATHOGENIC IN THE RESPIRATORY TRACT | |||
| RSV | 1 (2 subtypes: A and B) | Yesb | Bronchiolitis in <2 years and in elderly (also URTI, failure to thrive, febrile fits) |
| Influenza A | Genetically unstable → sequential variantsc | Yes | URTI, influenza |
| Influenza B | Genetically unstable → sequential variantsc | Yes | URTI, influenza, may include abdominal pain |
| Human metapneumovirus | 1 (2 subtypes: A and B) | Yes | Bronchiolitis in <2 years, and in elderly (also URTI, failure to thrive, febrile fits) |
| Parainfluenza | 1-4a,b | No | URTI, croup, bronchiolitis |
| Adenovirus | 47d | Yes | URTI, acute respiratory disease |
| Rhinovirus | >100 | No | URTI (‘common cold’) |
| Coronaviruse | 229E, OC43, NL63, HKU1 | No | URTI (‘common cold’), LRTI, croup, pneumonia |
| SARS-coronavirus | 1 | Yes | Severe and often fatal pneumonia |
| Epstein-Barr virus | 1 | Yesb | Glandular fever |
| Cytomegalovirus | 1 | Yesb | Various (in the immunocompromised only)f |
| Measles | 1 | Yesb | Measlesg |
| Hantaviruses | Several | No | Hantavirus pulmonary syndrome |
| Bocavirus | Only 1 known | ? | − |
| B. MAY BE RECOVERED FROM THE RESPIRATORY TRACT BUT ROLE IN RESPIRATORY DISEASE UNCERTAIN | |||
| Enteroviruses | 68 | No | − |
| Herpes simplex (hominis) | 1 | Yesb | –h |
| Reovirus | 3 | No | –i |
Although this column lists the more common presentations, there is considerable overlap in clinical signs and symptoms between respiratory viruses.
There is only one serotype. This is used as a group antigen for diagnostic purposes.
The RNA of influenza A and B viruses is constantly undergoing mutation which is reflected antigenically, causing ‘drift’ in both influenza A and B and ‘shift’ in influenza A.
Most respiratory infections are due to types 1–7.
Coronavirus 229E, OC43, NL63 and HKU1 viruses are now recognized.
Usually no overt illness in the immunocompetent, except congenital damage and for some examples of glandular fever.
Rash may be absent in the immunocompromised.
Causes stomatitis and may be a cause of pneumonitis in compromised patients.
No identified disease in man.