Clinical Presentation
Patients
with non-severe or uncomplicated
influenza present with sudden onset of cough, headache, muscle and joint pain,
severe malaise, sore throat, and rhinorrhea, with or without fever. While
severe influenza may lead to severe illness such as sepsis, septic shock,
severe pneumonia, acute respiratory distress syndrome, multi-organ failure, and
exacerbation of chronic medical conditions or death.
Clinical
Presentation of Seasonal Influenza
The typical signs
and symptoms of seasonal influenza include an abrupt onset of fever, severe
myalgia and/or arthralgia, dry cough, pleuritic chest pain, loss of
appetite, abdominal pain, diarrhea, headache, malaise, fatigue, sore throat,
and rhinitis.
Physical examination
of patients with seasonal influenza may present with flushing, pain on eye
movement, nonexudative pharyngitis, and scattered rales or rhonchi. Elderly
patients may have hot, dry, or diaphoretic skin.
Clinical
Presentation of Zoonotic Influenza
Avian Influenza
A(H5N1) Should Be Suspected in the Following:
- Documented temperature of >38°C and
- At least 1 of the following: Cough, sore throat, and/or shortness of breath and
- Contact history:
- History of contact with sick or dead poultry, family members with suspected or confirmed H5N1 infection, healthcare workers of suspected or confirmed H5N1 patients, laboratory workers handling specimens or viral cultures of H5N1 viruses
- History of living in an endemic area or an environment with sick or dead poultry
- If the patient only has a history of travel to endemic areas, a risk assessment will need to be individualized
Avian Influenza A
(H7N9)
Avian influenza A
(H7N9) is a subtype of influenza virus first reported in March 2013 in China.
Transmission is by direct contact with infected poultry or exposure to the
environment of infected poultry. No human-to-human transmission has been
recorded yet. Signs and symptoms are the same as seasonal influenza, but it is
most often accompanied by a history of severe pneumonia.
Other Reported
Presentations of Avian Influenza in Humans
Other presentations
include typical influenza-like symptoms (abrupt onset with headache, high-grade
fever, sore throat, chills, dry cough, malaise, myalgia, anorexia), dyspnea or
bloody sputum, chest pain, bleeding from the nose and gums, gastrointestinal
upset (vomiting, diarrhea, abdominal pain), neurological symptoms (eg stupor,
convulsions), conjunctivitis, pneumonia or pneumonitis, and acute respiratory
distress.