Influenza A occurs annually, during the late fall season, and strains change a little bit yearly, producing what we call “seasonal flu.” In April, 2009, we encountered a completely new strain of H1N1, the so-called “swine flu.”

The screening test for influenza is not very sensitive and needs additional confirmatory testing by the Department of Health or the CDC to diagnose H1N1. Due to the high volume of confirmatory flu testings requested, the Pennsylvania Department of Health is limiting testings to severe cases.

As a new strain, 2009 H1N1is behaving differently from the seasonal flu; it is affecting younger patients at an unusually high rate, and occurring at a time of the year when we don't typically see such intense flu activity. The typical seasonal flu may still occur later in the year, November and later.

When treatment is necessary, the same medications are prescribed for 2009 H1N1 and the seasonal flu, “antivirals” such as Tamiflu and Relenza.

Q: Should I get vaccinated with the H1N1 vaccine? Is it safe?

Dr. Liu: The Centers for Disease Control says the H1N1 vaccine is safe. The vaccine production went through the same manufacturing process as the seasonal flu vaccine which has been produced annually for decades.
The H1N1 vaccine is strongly recommended and prioritized for the following groups:
• Pregnant women
• People who live with or care for children younger than 6 months of age
• Healthcare and emergency medical services personnel
• Persons between the ages of 6 months and 24 years old
• People 25 through 64 years of age who are at higher risk for 2009 H1N1 because of chronic health disorders or compromised immune systems

If the supply of H1N1 vaccine is insufficient for the target group mentioned, the priority groups will be slightly different: pregnant women, people who live with or care for children younger than 6 months of age, health care and emergency medical services personnel with direct patient contact, children 6 months through 4 years of age, and children 5 through 18 years of age who have chronic medical conditions.

Once the target groups have been vaccinated, providers should begin vaccinating everyone from ages 25 through 64 years. Current studies indicate the risk for infection among persons age 65 or older is less than the risk for younger age groups. Therefore, as vaccine supply and demand for vaccine among younger age groups is being met, programs and providers should offer vaccination to people over the age of 65.

Q: Will the seasonal flu shot protect me at all from H1N1?

Dr. Liu: A seasonal flu shot will not protect you from H1N1, although there are different studies ongoing to see if there is some cross-protective activity.

Q: If my child gets the seasonal flu vaccine, can he/she receive the H1N1 vaccine right away, also?

Dr. Liu: H1N1 and Seasonal flu vaccinations both come as either an injection or a nasal spray. The nasal spray is a live-attenuated (weakened) (LAIV) vaccine and is not recommended for everybody. There must be 28 days—at least 21 days—between any two doses of live- vaccine.

CHILDREN under 10 years of age must receive TWO doses of the H1N1; if they get the live-attenuated virus vaccination (LAIV) which is recommended for young healthy people (between age 2 and 49 years old), they must wait at least 21 days, preferably 28, before the next dose. Injectable vaccine can be given at the same time or right after LAIV injections. In other words, your child can receive a shot after a nasal spray, but not two nasal sprays without 28 days (21 minimum) in between.

Q: If my 8-year-old gets the LAIV flu mist, does he shed the virus and possibly infect my infant daughter? What about others in my family who may have respiratory problems or pneumonia or a chronic illness such as diabetes?

Dr. Liu: In studies done, transmission rarely occurs (0.6 to 2.4%); and even with transmission, it is unlikely to result in clinical illness. Although the vaccine can cause runny nose, nasal congestion, cough, sore throat, headache, chills, symptoms are generally mild.

The LAIV vaccine contains a weakened ( attenuated) strain and can be used in people who take care of others with weakened immune systems ( as in health-care workers); except in instances where they take care of severely immuno-compromised patients such as bone marrow transplant patients while they are still in the hospital in the special isolation unit.

Q: Should I buy face masks to protect myself and my family?

Dr. Liu: In general, face masks are not recommended in the community or home-setting.

If you are suffering flu or flu-like symptoms- cough, fever, diarrhea, headache, or you are in the high risk group susceptible to severe flu—you should avoid public places or close contacts (within 6 feet of other people) if possible. When contact is unavoidable, consider acquiring a mask when you are around other people in close proximity, especially if you visit a public setting such as your doctor’s office or local hospital. Many of these places offer masks at the front door.

Q: Do those that have been previously vaccinated against the 1976 swine influenza need to get vaccinated against the 2009 H1N1 influenza?

Dr. Liu: The 1976 swine flu virus and the 2009 H1N1 virus are different enough that it’s unlikely a person vaccinated in 1976 will have full protection from the 2009 H1N1. People vaccinated in 1976 should still be given the 2009 H1N1 vaccine.

Q: If I get a mild case of H1N1 flu now, am I immune to a more serious case and don't need the vaccine?

Dr. Liu: If you really did have H1N1, you would most likely be immune and have some protection. However, unless your illness has been confirmed to be H1N1 and not something else, the CDC is still recommending the vaccine.

Q: Will my doctor have the H1N1 vaccine or do I have to go to a hospital?

Dr. Liu: The Centers for Disease Control (CDC) is shipping the vaccine to hospitals, clinics, doctor’s offices, health departments, and other providers of vaccines that have been designated as vaccine-receiving sites. In Pennsylvania, the Department of Health (DOH) is allocating the vaccines to doctors’ offices, clinics, hospitals and schools that have ordered doses through the DOH. You should ask your primary healthcare provider—your doctor or nurse practitioner—where you should go and what type of vaccine, injection or nasal, is best for you and your family. Or call the local office of the State Department of Health. *

Q: Are there other ways to prevent the spread of flu?

Dr. Liu: Yes, beginning with proper hygiene and respiratory “etiquette"
* Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.