About Seasonal Influenza

Influenza is a highly contagious viral infection that affects mainly the nose, throat, chest and lungs. The flu may cause mild to severe illness, and may even lead to death. In the very young, the elderly, and those with other serious medical conditions, infection can lead to severe complications such as pneumonia. 

Symptoms of Influenza

Symptoms of influenza include:

• Fever (typically ≥100° F)
• Headache
• Extreme tiredness
• Dry cough
• Sore throat
• Runny or stuffy nose
• Muscle aches
• Stomach symptoms, such as nausea, vomiting, and diarrhea, also can occur but are more common in children than in adults.
• Infectious Period
• People may be able to infect each other one day before symptoms occur and up to 10 days after being sick.

The Spread of Influenza

Flu viruses mainly spread from person to person through coughing or sneezing of people with influenza. Sometimes people may become infected by touching something with flu viruses on it and then touching their mouth or nose. Most healthy adults may be able to infect others beginning one day before symptoms develop and up to five days after becoming sick. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick.

How can you prevent the flu?

The single best way to prevent the flu is to get vaccinated each year. There are two types of vaccines:

The “flu” shot- an inactivated vaccine (containing killed virus) that is given with a needle. The flu shot is approved for use in people six months of age and older, including healthy people and people with chronic medical conditions.

The nasal-spray flu vaccine- a vaccine made with live, weakened flu viruses that do not cause the flu (sometimes called LAIV for “Live Attenuated Influenza Vaccine” or FluMist ®). LAIV is approved for use in healthy people 2-49 years of age who are not pregnant.

About two weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against flu-like illnesses caused by non-influenza viruses.

If you get the flu:

• Stay home from work or school
• Make sure and get plenty of rest and water
• Over-the-counter medications may relieve symptoms
• Consult your doctor.

H1N1 Update

Sixteen months after reports of a potentially fatal new influenza virus took the world and media by storm, the World Health Organization (WHO) declared an end to the 2009 H1N1 pandemic on August 10, 2010. Although the Phase 6 alert has been lifted and H1N1 is no longer the dominant influenza virus it once was, evidence from prior pandemics suggests that the virus will come to model the behavior of seasonal influenza and continue to circulate for years to come. Fortunately, global preparedness efforts and a swift public health response resulted in rapid detection and reporting of cases, extensive vaccination coverage for some high risk populations, and a legacy of stronger influenza control efforts even in communities with weaker health systems.

This special 1st anniversary session of Public Health Grand Rounds will review the roles that preparedness, surveillance, vaccine development, and risk communication played in the H1N1 response, discuss lessons learned, and tackle the myths and truths of this controversial and still relevant public health issue.

Stephen C. Redd, MD
Rear Admiral and Assistant Surgeon General, United States Public Health Service; Director, Influenza Coordination Unit, Office of Infectious Diseases, CDC
Myths and Misconceptions of the 2009 H1N1 Pandemic

Michael W. Shaw, PhD
Associate Director for Laboratory Science, Influenza Division, National Center for Immunization and Respiratory Diseases, CDC
The Pandemic Laboratory Response

Daniel B. Jernigan, MD, MPH
Deputy Director, Influenza Division, National Center for Immunization and
Respiratory Diseases, CDC
Epidemiology and Surveillance for Pandemic Response

Julie Morita, MD
Deputy Commissioner, Bureau of Public Health and Safety, Chicago Department of Public Health
Chicago Response to the H1N1 Pandemic: Strategy and Partnerships at the City Level

Vincent T. Covello, PhD
Director of the Center for Risk Communication, New York City, New York
H1N1 Risk and Crisis Communication: Successes and Challenges

Facilitated by:
Tanja Popovic, MD, PhD, Scientific Director, Public Health Grand Rounds
Shane Joiner, Communication Manager, Public Health Grand Rounds