CDH releases fact sheet on 2009 H1N1 Flu

Tuesday, October 20, 2009

What is 2009 H1N1 (swine flu)?

2009 H1N1 (referred to as "swine flu" early on) 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. On June 11, 2009, the World Health Organization (WHO) signaled that a pandemic of 2009 H1N1 flu was underway.

Why is 2009 H1N1 virus sometimes called "swine flu"?

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.

How does 2009 H1N1 virus spread?

Spread of 2009 H1N1 virus is thought to occur 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 -- such as a surface or object -- with flu viruses on it and then touching their mouth or nose.

What are the signs and symptoms of this virus in people?

The symptoms of 2009 H1N1 flu virus in people include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. A significant number of people who have been infected with this virus also have reported diarrhea and vomiting. Severe illnesses and death has occurred as a result of illness associated with this virus.

The symptoms of H1N1 flu are almost identical to those of seasonal flu.

How severe is illness associated with 2009 H1N1 flu virus?

Illness with the new H1N1 virus has ranged from mild to severe. While most people who have been sick have recovered without needing medical treatment, hospitalizations and deaths from infection with this virus have occurred.

In seasonal flu, certain people are at "high risk" of serious complications. This includes people 65 years and older, children younger than five years old, pregnant women, and people of any age with certain chronic medical conditions.

Information analyzed by CDC seems to indicate that 2009 H1N1 flu causes more illness in people younger than 25 years of age than in older people.

About 70 percent of people who have been hospitalized with this 2009 H1N1 virus have had one or more medical conditions previously recognized as placing people at "high risk" of serious seasonal flu-related complications. This includes pregnancy, diabetes, heart disease, asthma and kidney disease.

One thing that appears to be different from seasonal influenza is that adults older than 64 years do not yet appear to be at increased risk of 2009 H1N1-related complications thus far.

How does 2009 H1N1 flu compare to seasonal flu in terms of its severity and infection rates?

With seasonal flu, the seasons vary in terms of timing, duration and severity. Seasonal influenza can cause mild to severe illness, and at times can lead to death.

Each year, in the United States, on average 36,000 people die from flu-related complications and more than 200,000 people are hospitalized from flu-related causes. Of those hospitalized, 20,000 are children younger than 5 years old. Over 90% of deaths and about 60 percent of hospitalization occur in people older than 65.

The 2009 H1N1 flu seems to cause more illness in people younger than 25 years of age than among than older people. At this time, there are few cases and few deaths reported in people older than 64 years old, which is unusual when compared with seasonal flu.

However, pregnancy and other previously recognized high risk medical conditions from seasonal influenza appear to be associated with increased risk of complications from this 2009 H1N1. These underlying conditions include asthma, diabetes, suppressed immune systems, heart disease, kidney disease, neurocognitive and neuromuscular disorders and pregnancy.

How long can an infected person spread this virus to others?

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 can I do to protect myself from getting sick?

The single best way to prevent seasonal flu is to get a seasonal flu vaccination each year. When the H1N1 flu vaccine becomes available you should make an effort to get that vaccination as well.

There are everyday actions that can help prevent the spread of germs that cause respiratory illnesses like influenza.

Take these everyday steps to protect your health:

* Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.

* Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.

* Avoid touching your eyes, nose or mouth. Germs spread this way.

* Try to avoid close contact with sick people.

* If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.) Keep away from others as much as possible to keep from making others sick.

Other important actions that you can take are:

* Follow public health advice regarding school closures, avoiding crowds and other social distancing measures.

* Be prepared in case you get sick and need to stay home for a week or so; a supply of over-the-counter medicines, alcohol-based hand rubs, tissues and other related items might could be useful and help avoid the need to make trips out in public while you are sick and contagious

If I have a family member at home who is sick with 2009 H1N1 flu, should I go to work?

Employees who are well but who have an ill family member at home with 2009 H1N1 flu can go to work as usual. These employees should monitor their health every day, and take everyday precautions including washing their hands often with soap and water, especially after they cough or sneeze. Alcohol-based hand cleaners are also effective.

If they become ill, they should notify their supervisor and stay home. Employees who have an underlying medical condition or who are pregnant should call their health care provider for advice, because they might need to receive influenza antiviral drugs to prevent illness.

What should I do if I get sick?

You should stay home and avoid contact with other people. CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)

Stay away from others as much as possible to keep from making others sick. Staying at home means that you should not leave your home except to seek medical care. This means avoiding normal activities, including work, school, travel, shopping, social events, and public gatherings.

If you have severe illness or you are at high risk for flu complications, contact your health care provider or seek medical care. Your health care provider will determine whether flu testing or treatment is needed.

If you become ill and experience any of the following warning signs, seek emergency medical care.

In children, emergency warning signs that need urgent medical attention include:

* Fast breathing or trouble breathing.

* Bluish or gray skin color.

* Not drinking enough fluids

* Severe or persistent vomiting

* 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.

In adults, emergency warning signs that need urgent medical attention include:

* Difficulty breathing or shortness of breath.

* Pain or pressure in the chest or abdomen.

* Sudden dizziness.

* Confusion.

* Severe or persistent vomiting.

* Flu-like symptoms improve but then return with fever and worse cough.

Can I get infected with 2009 H1N1 virus from eating or preparing pork?

No. 2009 H1N1 viruses are not spread by food. You cannot get infected with novel HIN1 virus from eating pork or pork products. Eating properly handled and cooked pork products is safe.

To better reach those in priority groups first, CDHD is also coordinating and supporting the following activities:

Joint efforts between CDHD and school nurses to vaccinate K--12 public school students in Ada County, McCall, and Glenns Ferry.

Distribute vaccine to some obstetrician clinics for pregnant females (call your provider to get more info).

Distribute vaccine to homebound individuals through their home health agencies (call your agency for more information).

Administer vaccine to first responders and healthcare workers.

Distribute vaccine to jails, prisons or other detention centers for vaccination of high priority groups.

Once good coverage of priority groups has been achieved (this is expected to take 4--5 weeks) CDHD will encourage all citizens to protect themselves, coworkers and the community by getting the H1N1 flu vaccination. CDHD will make the vaccine more broadly available in the community through health providers and through special flu clinics at the three district offices in Boise, McCall and Mountain Home.

Getting the H1N1 flu shot is important even if the number of reported cases is low and severity of the disease mild. Public health expects the H1N1 flu will continue through the fall and winter, and possibly through summer and into the next flu season. To decrease the burden of disease in the community and protect those at greatest risk for poor outcomes, CDHD encourages everyone who is able to receive the vaccine to get it.

Will there be a charge for getting the H1N1 flu vaccination?

No. All vaccines administered through the public health departments will be free of charge. Later, when private health providers begin administering the vaccine, there may be an administration charge.Facts about flu vaccinations

Both the seasonal and H1N1 flu vaccines will be made available in two forms:

* The "flu shot" -- an inactivated vaccine (containing killed virus) that is given with a needle. The seasonal flu shot is approved for use in people 6 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"). 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.

A seasonal flu vaccine will not protect you against the new 2009 H1N1 flu. And the vaccine against the new H1N1 flu will not protect you against the seasonal flu.

Who can use the Nasal Spray Flu Vaccine?

Vaccination with the nasal-spray flu vaccine is an option for healthy people 2-49 years of age who are not pregnant, even healthy persons who live with or care for those in a high risk group. The one exception is healthy persons who care for persons with severely weakened immune systems who require a protected environment; these healthy persons should get the inactivated flu vaccine.

Who Should Not Be Vaccinated Against Seasonal Flu?

Some people should not be vaccinated without first consulting a physician. They include:

* People who have a severe allergy to chicken eggs.

* People who have had a severe reaction to an influenza vaccination in the past.

* People who developed Guillian-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.

* Children less than 6 months of age (influenza vaccine is not approved for use in this age group).

* People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.

If you have questions about whether you should get a flu vaccine, consult your health-care provider.

Will two doses of vaccine be required?

The U.S. Food and Drug Administration (FDA) has approved the use of one dose of 2009 H1N1 flu vaccine for persons 10 years of age and older.

Children younger than 10 years should receive two doses of 2009 H1N1 flu vaccine. This is slightly different from CDC's recommendations for seasonal influenza vaccination which state that children younger than 9 who are being vaccinated against influenza for the first time need to receive two doses. Infants younger than 6 months of age are too young to get the 2009 H1N1 and seasonal flu vaccines.

If I've already had the flu do I need to get the H1N1 flu vaccine?

Yes. It is recommended that you get the H1N1 flu vaccine even if you've had the flu because without a blood test confirming the type of flu you've had, you can't be certain you had H1N1 flu. You should also get your seasonal flu shot for the same reason.

Are flu vaccines, including the one for H1N1, safe?

The CDC expects the 2009 H1N1 influenza vaccine to have a similar safety profile as seasonal flu vaccines, which have a very good safety track record.

CDC expects that any serious side effects following vaccination with the 2009 H1N1 influenza vaccine would be rare.

If side effects occur, they will likely be similar to those experienced following seasonal influenza vaccine.

The CDC and FDA closely monitor the safety of seasonal influenza and other vaccines licensed for use in the United States in cooperation with state and local health department, healthcare providers, and other partner.

Mercury in Vaccines - Thimerosal

Thimerosal is a mercury-based preservative that is used in some influenza vaccines to keep them free from contamination of microorganisms.

The 2009 H1N1 influenza vaccine is being manufactured in several formulations.

Various vaccine manufacturers will be producing some of the 2009 H1N1 influenza vaccine in single-dose units, which will not require the use of thimerosal as a preservative.

The live-attenuated version of the vaccine, which is administered intranasally (through the nose), is produced in single-units and will not contain thimerosal.

Some vaccine will come in multi-dose vials and will contain thimerosal as a preservative.

Multi-dose vials of seasonal influenza vaccine contain thimerosal to prevent potential contamination after the vial is opened. Seasonal flu vaccines that do not contain thimerosal are available.

Guillain-Barré syndrome (GBS)

Guillain-Barré syndrome (GBS) is a medical condition in which the body damages its own nerve cells, causing muscle weakness and sometimes paralysis. Most people who develop GBS fully recover, but in some cases, death can result, usually from difficulty breathing.

It is not fully understood why some people develop GBS, but it often occurs following infection. It is believed that stimulation of the body's immune system may play a role in its development.

The infection that most commonly precedes GBS is caused by a bacterium called Campylobacter jejuni. Influenza virus infection has also been associated with GBS.

In 1976, there was a small risk of GBS following influenza (swine flu) vaccination (approximately 1 additional case per 100,000 people who received the swine flu vaccine). That number of GBS cases was slightly higher than the background rate for GBS. Since then, numerous studies have been done to evaluate if other flu vaccines were associated with GBS. In most studies, no association was found, but two studies suggested that approximately 1 additional person out of 1 million vaccinated people may be at risk for GBS associated with the seasonal influenza vaccine.

FDA and CDC and several partners will be closely monitoring reports of serious vaccine adverse events, including GBS, following the 2009 H1N1 influenza vaccination.

Are there medicines to treat 2009 H1N1 infection?

Yes. CDC recommends the use of antivirals for the treatment and/or prevention of infection with 2009 H1N1 flu virus. Antiviral drugs are prescription medicines (pills, liquid or an inhaled powder) that fight against the flu by keeping flu viruses from reproducing in your body.

If you get sick, antiviral drugs can make your illness milder and make you feel better faster. They may also prevent serious flu complications. During the current pandemic, the priority use for influenza antiviral drugs is to treat severe influenza illness (for example hospitalized patients) and people who are sick who have a condition that places them at high risk for serious flu-related complications.

What are the treatment benefits of influenza antiviral drugs?

For treatment, antiviral drugs should be started within 2 days after becoming sick. When used this way, these drugs can reduce the severity of flu symptoms and shorten the time you are sick by 1 or 2 days. They may also prevent serious flu complications.

Antiviral drugs may be especially important for people who are very sick (hospitalized) or people who are sick with the flu and who are at increased risk of serious flu complications, such as pregnant women, young children and those with chronic health conditions.

How effective are antiviral drugs at preventing the flu?

When used to prevent the flu, antiviral drugs are about 70% to 90% effective against susceptible viruses (i.e., viruses that are not resistant to the antiviral medication). It's important to remember that flu antiviral drugs are not a substitute for getting a flu vaccine.

Who is prioritized for treatment with influenza antiviral drugs?

Most people ill with influenza will recover without complications.

Some people are at highest risk of influenza-related complications and are prioritized for treatment with influenza antiviral drugs this season. They include:

* People with more severe illness, such as those hospitalized with suspected or confirmed influenza

* People with suspected or confirmed influenza who are at higher risk for complications

* Children younger than 2 years old

* Adults 65 years and older

* Pregnant women

* People with certain chronic medical or immunosuppressive conditions

* People younger than 19 years of age who are receiving long-term aspirin therapy

Children 2 years to 4 years old are more likely to require hospitalization or urgent medical evaluation for influenza compared with older children, although the risk is much lower than for children younger than 2 years old. Children aged 2 years to 4 years without high risk conditions and who are not severely ill do not necessarily require antiviral treatment.

Children and adults presenting with suspected influenza who have symptoms of lower respiratory tract illness or clinical deterioration should also receive prompt empiric antiviral therapy, regardless of previous health or age.

Physicians may also decide not to treat some people in these groups and/or treat people who are not in these groups based on their clinical judgment.

If I get sick with flu-like illness do I need to get tested to see if it's H1N1?

Your medical provider can help you decide whether to test for H1N1. Most people who have been sick with H1N1 flu have recovered without needing medical treatment, so your medical provider may decide it may not be worth the expense to test.

The Idaho Bureau of Laboratories (IBL) has set its testing priorities. IBL will test suspect H1N1 specimens if a patient has a fever and cough and/or a sore throat and is hospitalized or seriously ill, works in a hospital setting, is pregnant or is part of an outbreak or cluster of cases that have been reported to the health department and has authorized for specimens to be submitted to IBL.

What if I've been exposed to someone with H1N1 flu?

If you believe that you have been exposed to any other type of influenza you should:

* Watch for the signs and symptoms of influenza which include: fever greater than 100.5; sore throat, cough, body aches, runny nose, fatigue, and/or diarrhea and vomiting.

* Do not go to work or school or child care if you develop symptoms of influenza.

* Contact your doctor if you are pregnant or have a special health condition like diabetes, heart disease, asthma or emphysema.

* Seek emergency medical care if you or a person you are caring for develops difficulty breathing or chest pain; the lips turn blue; you are vomiting and unable to keep food or liquids down; develop signs of dehydration or seizures.

I've gotten sick after getting the flu shot in the past; can I get sick from the flu shot?

No, but you may have been exposed to the flu prior to getting the vaccine or shortly after. It will take approximately 8-11 days for the vaccine to become effective in persons 10 and older, and up to 6 weeks for those under 10 years of age (for children under 10 years, 2 doses are required for full immunity from H1N1).

Additional Resources:

* Central District Health Department

* Flu Hotline 321-2222 or 1-800-962-2343


* Centers for Disease Control and Prevention (CDC):"

* State of Idaho Flu Information:

* Pandemic Flu Idaho:

* Idaho State Department of Education:

* World Health Organization (WHO):