Influenza Virus

Clinical Overview of Influenza

Influenza is a serious, contagious respiratory illness that affects 5 to 20 percent of the United States population every year²
Every year, seasonal flu is responsible for approximately 36,000 deaths and 226,000 hospitalizations in the U.S. More about the impact of influenza³
Influenza A and B viruses are the two types that cause epidemic disease ³
New variants of the influenza virus emerge regularly due to mutations that occur during viral replication³

Influenza is spread from person to person through respiratory droplets that are dispersed when an infected person coughs or sneezes in close proximity to someone who is not infected
The typical incubation period is 1 to 4 days, with an average of 2 days
Adults can be infectious from 1 day before onset of symptoms to 5 days after illness onset
Children can be infectious for 10 days or more after onset of symptoms, and young children can shed the virus before their illness onset
Uncomplicated influenza is characterized by abrupt onset of signs and symptoms that can include:
- Fever
- Chills
- Myalgia
- Headache
- Tiredness
- Non-productive cough
- Sore throat
- Rhinitis
Uncomplicated influenza typically resolves within 1 week, although cough and malaise can persist for up to 2 weeks ³

Complications of influenza can include:

Bacterial pneumonia
Ear infections
Sinus infections
Dehydration
Worsening of chronic medical conditions such as congestive heart failure, asthma or diabetes ²

Patients at high risk for influenza-related complications and severe disease include:

Pediatric patients aged 6 to 59 months
Pregnant women
Patients aged 50 years and older
Patients of any age with chronic medical conditions
Patients who live with or care for persons at high risk such as household contacts and healthcare workers ³

Access tools for helping your patients know the facts about influenza.

Minimize the impact of influenza season on your practice.