Frequently Asked Questions (FAQ):

What Is H1N1 Influenza?

  2009 H1N1, sometimes called "swine flu", is a new influenza virus causing illness in people. This new virus was first detected in people in the United States in April 2009. This virus is spreading from person-to-person worldwide, probably in much the same way that regular seasonal influenza viruses spread. This virus was originally referred to as "swine flu" because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs (swine) in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and bird (avian) genes and human genes. Scientists call this a "quadruple reassortant" virus.

What Are The Symptoms Of The H1N1 Flu?

The symptoms of 2009 H1N1 flu virus in people include:
  • fever
  • cough
  • sore throat
  • runny or stuffy nose
  • body aches
  • headache
  • chills
  • fatigue
Some people may have vomiting and diarrhea. People may be infected with the flu, including 2009 H1N1 and have respiratory symptoms without a fever. Severe illnesses and deaths have occurred as a result of illness associated with this virus.

How Does The Flu Spread?

The main way that influenza viruses are thought to spread is from person to person in respiratory droplets of coughs and sneezes. This can happen when droplets from a cough or sneeze of an infected person are propelled (generally up to 3 feet) through the air and deposited on the mouth or nose of people nearby. The viruses also can spread when a person touches respiratory droplets on another person or an object and then touches their own mouth or nose (or someone else’s mouth or nose) before washing their hands.  
How H1H1 Is Spread

How Long Is Someone Considered "Contagious"?

People infected with seasonal and 2009 H1N1 flu shed virus and may be able to infect others from 1 day before getting sick to 5 to 7 days after. This can be longer in some people, especially children and people with weakened immune systems and in people infected with the new H1N1 virus.

What Is The Difference Between 'Seasonal' and 'H1N1' Flu?

The flu appears from year to year in different forms or "strains". H1N1 is one of these strains. The difference with H1N1 is that it is a new strain of influenza not seen for many years and therefore no one has any natural immunity to it. The H1N1 strain has the potential to cause more illness or more severe illness than the seasonal strain. H1N1 has already demonstrated the ability to spread quickly and globally, quickly creating a pandemic, which is the term used to indicate the spread of a disease from continent to continent. Similarities:
  • Symptoms - Symptoms of H1N1 and seasonal flu are very similar, and include fever, body aches, headache, sore throat, cough, runny/stuffy nose, chills, fatigue, and possibly diarrhea and/or vomiting.
  • How it’s spread - The spread of the H1N1 virus is thought to be happening in the same way that seasonal flu spreads. Flu viruses are spread mainly from person-to-person through coughing or sneezing by people with influenza. Sometimes people may become infected by touching something with flu viruses on it and then touching their mouth or nose.
  • Who is impacted - While everyone is at risk for contracting H1N1, so far the number of cases and deaths reported from H1N1 are less among the people over the age of 64 than that of the seasonal flu. In addition, the CDC reports that novel H1N1 flu has caused greater disease burden in people younger than 25 years of age than older people.
  • Vaccinations - Currently there is no vaccination against H1N1. However, a vaccination is being developed and will likely be available later this year. The seasonal flu has a vaccine developed annually in order to help people protect themselves. Find out more information about how to protect yourself against seasonal flu by visiting and read our H1N1 blog for the latest information on H1N1 and vaccine development.

How Can I Help Prevent Influenza?

  • Vaccinate - This is the single best way to help prevent the flu.
  • Wash Your Hands - Washing your hands OFTEN will help protect you from not only influenza, but other germs as well.
  • Avoid Touching Your Eyes, Nose, or Mouth - This includes licking your fingers to turn pages of paper, and rubbing your eyes. Germs are often spread when a person touches something that is contaminated with germs and then touches their eyes, nose, or mouth.
  • Cover Your Mouth and Nose - Cough or sneeze into your shirt sleeve or cover your mouth and nose with a tissue. It may prevent those around you from getting sick.
  • Avoid Close Contact - Avoid close contact with people who are sick. Keep your distance from others when you are sick to protect them from getting sick as well.
  • Stay Home When You Are Sick - If possible, stay home from work, school and errands when you are sick.
  • Practice Other Good Health Habits - Get plenty of sleep, be physically active, manage your stress, drink plenty of fluids and eat nutritious foods.

Should I Get Vaccinated?

  The best way to prevent H1N1 flu is by getting an H1N1 vaccination. Since the seasonal flu and H1N1 flu are indeed different strains of influenza it is necessary to receive separate vaccines specifically engineered for each virus in order to protect yourself from each strain. In the United States, on average 5% to 20% of the population gets the seasonal flu; more than 200,000 people are hospitalized from seasonal flu-related complications, and; about 36,000 people die from seasonal flu-related causes. Some people, such as older people, young children, pregnant women, and people with certain health conditions, are at high risk for serious flu complications. The H1N1 strain has already reached pandemic levels and has clearly demonstrated an ability to easily transmit from human to human. Therefore, as with the seasonal flu, it is important to get vaccinated to help stop the spread of the disease

What About "Thimerosol"? Is It Safe?

Thimerosal is a very effective preservative that has been used since the 1930s to prevent contamination in some multi-dose vials of vaccines. There is no convincing evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site. However, in July 1999 the Public Health Service (PHS) agencies, the American Academy of Pediatrics (AAP), and vaccine manufacturers agreed that thimerosal should be reduced or eliminated in vaccines as a precautionary measure. For more information concerning thimerosol please visit the CDC's Thimerosol web page.

Should I Seek Medical Treatment?

The American College of Emergency Physicians has issued guidelines on when to visit an emergency room for the flu. While it is usually not necessary to go to the Emergency Room for the flu, the following symptoms may indicate a serious condition requiring immediate medical care.
  • In Children
    • Fast breathing or trouble breathing
    • Bluish skin color
    • Not drinking enough fluids
    • Not waking up or not interacting
    • Being so irritable that the child does not want to be held
    • Flu-like symptoms improve but then return with fever and worse cough
    • Fever with a rash
  • In Adults
    • Difficulty breathing or shortness of breath
    • Pain or pressure in the chest or abdomen
    • Sudden dizziness
    • Confusion
    • Severe or persistent vomiting
If possible, consult your family physician first to see what he/she recommends. If in doubt and severe symptoms do exist don't wait, seek emergency medical care.

Where Can I Find More Information?

For more information regarding H1N1 please visit the Centers for Disease Control H1N1 web page.