ad
This Article
Right arrow Images Only
Right arrow Full Version
Right arrow Update: 2010-2011 Influenza Statement and Guidance
Right arrow Update: Mandatory Influenza Immunization for HCP
Right arrow Update: Egg Allergy and Influenza Vaccine
Services
Right arrow E-mail this link to a friend
Right arrow Add to My File Cabinet
Right arrow Download to citation manager
Right arrow reprints & permissions
Right arrow Section 1
Section 2
Section 3
Section 4
Section 5
Appendices
Right arrow Earn CME - What's This?

The first 300 words of the full text of this section appear below.

Section 3. Summaries of Infectious Diseases

Influenza

Clinical Manifestations
Etiology
Epidemiology
Diagnostic Tests
Treatment
Isolation of the Hospitalized Patient
Control Measures

Top
 Next
See Images

CLINICAL MANIFESTATIONS

Influenza typically begins with the sudden onset of fever, often accompanied by chills or rigors, headache, malaise, diffuse myalgia, and nonproductive cough. Subsequently, respiratory tract signs including sore throat, nasal congestion, rhinitis, and cough become more prominent. Conjunctival injection, abdominal pain, nausea, vomiting, and diarrhea less commonly are associated with influenza illness. In some children, influenza can appear as an upper respiratory tract infection or as a febrile illness with few respiratory tract signs. Influenza is an important cause of otitis media. Acute myositis characterized by calf tenderness and refusal to walk has been described. In infants, influenza can produce a sepsis-like picture and occasionally can cause croup, bronchiolitis, or pneumonia. Although the large majority of children with influenza recover fully after 3 to 7 days, previously healthy children can have severe symptoms and complications. Neurologic complications associated with influenza range from febrile seizures to severe encephalopathy and encephalitis with status epilepticus, with resulting neurologic sequelae or death. Reye syndrome has been associated with influenza infection. Death from influenza-associated myocarditis has been reported. Invasive secondary infections or coinfections with group A streptococcus, Staphylococcus aureus (including methicillin-resistant S aureus [MRSA]), Streptococcus pneumoniae, or other bacterial pathogens can result in severe disease and death.


Top
 Previous
Next
See Images

ETIOLOGY

Influenza viruses are orthomyxoviruses of 3 genera or types (A, B, and C). Epidemic disease is caused by influenza virus types A and B, and both influenza A and B virus antigens are included in influenza vaccines. Type C influenza viruses cause sporadic mild influenza-like illness in children, and type C antigens are not included in influenza vaccines. Influenza A viruses are subclassified into subtypes by 2 surface antigens, hemagglutinin (HA) and neuraminidase . . . [Go to Full Text]