The ABCs of H1N1

Last Updated: 11th October 2009, 3:29am
What is H1N1?
2009 H1N1, once referred to as "swine flu," is a new influenza virus first detected in people in the U.S. in April, 2009. It is now spreading person-to-person worldwide, in much the same way that regular seasonal influenza spreads.
On June 11, 2009, the World Health Organization (WHO) signaled that a pandemic of 2009 H1N1 flu -- which is distinct from past versions of H1N1 in several ways --was underway.
It is believed that the virus first made the leap to infecting humans in La Gloria, Mexico, about three hours outside Mexico City.
The disease was originally nicknamed swine flu because it is believed the virus that now infects humans originated in pigs, though the virus contains genes from swine, bird and human flu viruses.
The flu viruses that spread among pigs aren't the same as human flu viruses. It is extremely rare for swine flu to infect people. Those rare human cases that have occurred mainly affect people who have direct contact with pigs through their work.
The current outbreak is different, though. It is caused by a virus that has mutated, allowing it to spread easily from person to person, creating an entirely new disease.
To distinguish it from flu viruses that mainly infect pigs, and from the seasonal influenza H1N1 viruses that have been in circulation for many years, the CDC calls the virus "2009 H1N1 virus."
how is it spread
The new H1N1 swine flu virus spreads just like regular flu. It can be picked up directly from the cough or sneeze of an infected person, or simply by touching an object contaminated by the cough or touch of an infected person and then touching your eyes, mouth or nose. It's just one more reason why you should make washing your hands a regular habit, even when you're not ill.
Incubation period: Between two and seven days.
immunity
Many people have at least partial immunity to seasonal flu viruses through previous infections or vaccinations. But these viruses "drift" genetically -- meaning they change over time -- which is one reason why the flu vaccine has to be tweaked every year.
But the new H1N1 virus is not the usual "drift variant" of H1N1. It's come to humans from a different evolutionary line. That means very few people have any natural immunity to the new H1N1. The normal seasonal flu shot offers no protection against this new virus.
Dig out your tape measure. If you get swine flu, you should stay at least 6 feet away from others to help them avoid getting sick. Check out how far away that is.
Who is most at risk?
Certain groups are at higher risk than others of experiencing severe, and sometimes deadly, symptoms if they get the flu. People in these groups should seek medical care as soon as they get flu symptoms.
Pregnant women are six times more likely to have severe flu disease than women who are not pregnant.
Young children, especially those under 2 years of age.
People with cardiovascular conditions (except high blood pressure).
People with liver problems.
People with kidney problems.
People with blood disorders, including sickle cell disease.
People with neurological disorders.
People with neuromuscular disorders.
People with metabolic disorders, including diabetes.
People with immune suppression, including HIV patients, those taking anti-rejection drugs for transplants or cancer patients.
Residents of a nursing home or other chronic-care facility.
Infectious period
People infected with the seasonal or H1N1 flu virus may be able to infect others from 1 day before getting sick up to 7 days after. This can be longer in some people, especially children or people with weakened immune systems.
How will you know if you have it?
If you know of an H1N1 outbreak in your area and you begin to experience any of the outlined symptoms, you may have contracted the virus. But that doesn't mean that any old case of the sniffles is a reason to panic.If you suspect anything, though, it's best to see your doctor.
Your doctor may or may not test you for the new H1N1 virus by taking samples from your nose or throat and sending the cultures off to a lab.
The symptoms of the new H1N1 flu are similar to seasonal flu, but may include additional symptoms such as vomiting and diarrhea.
Is it Cold or flu?
How do you know if you have the flu or a cold? Doctors recommend taking your temperature as a first step. Symptoms such as nasal congestion, cough, aches and malaise are a part of colds, seasonal and H1N1 flu. But a common cold rarely has symptoms of fever above 101F. Flu symptoms, however, includ an initial fever accompanied by body and muscle aches.
Relatively few 2009 H1N1 flu caseshave been seen in people over age 65.
Flu viruses enter your body through the mucous membranes of your nose, eyes or mouth.
Prevention tips
Wash your hands regularly with soap and water, especially after coughing or sneezing. Scrub for at least 20 seconds and rinse thoroughly.
If soap and water are not available, wash your hands with an alcohol-based hand gel. Rub your hands together until the alcohol dries completely.
Avoid close contact (being within 2 metres) with people who have flu-like symptoms.
Avoid touching your mouth, nose, or eyes.
If you have flu-like symptoms stay home until you've been symptom-free for 24 hours.
Breastfeeding mothers with flu symptoms should express their breast milk and feed their child by other means.
handwashing 101
Singing Happy Birthday through once is how long you should spend on handwashing, say experts. Remove jewelry, lather soap and scrub palm to palm, then between and around fingers, the back of each hand, and fingertips. Rinse, then pat dry with paper towel before using the towel to turn off the faucet.
When to call the doctor
If you only have mild flu symptoms, you do not need medical attention unless your illness worsens. But if you are in one of the high-risk groups, contact your doctor at the first sign of flu-like illness. In such cases, the Centre for Disease Control recommends that people call or email their doctor before rushing to an emergency room.
If you already have flu or cold symptoms, call your doctor if you develop any of the following severe symptoms:
Persistent fever: May be a sign of another bacterial infection that should be treated.
Painful swallowing: Severe pain could mean strep throat, which requires treatment by a doctor.
Persistent coughing: If a cough persists for more than two or three weeks, it could be bronchitis, which may need an antibiotic. Postnasal drip or sinusitis can also result in a persistent cough.
Persistent congestion and headaches: Colds and allergies can lead to sinus infection. If you have pain around the eyes and face with thick nasal discharge after a week, you may have a bacterial infection and need an antibiotic.
Get emergency medical treatement if you have:
- Severe chest pain
- Severe headache
- Shortness of breath
- Dizziness
- Confusion
- Persistent vomiting
In children:
- Difficulty breathing or rapid breathing
- Bluish or grey skin color
- Not drinking enough fluids
- Are not waking up
- Lethargy and failure to interact normally
- Extreme irritability or distress
- Symptoms that were improving suddenly worsen
- Fever with a rash
2009 H1N1
(swine) flu is NOT caused by eating pork or pork products. No variety of flu is a foodborne disease.
Things to Do Before You Get Swine Flu
Make a backup plan. What will you do if you need to stay home from your workplace, college, or school? Do you have paid sick days? If you're in school, can you still keep up with class work? Don't wait until the last minute to find out.
Find a friend or neighbour that can help out. Will you need someone to drive your kids to school or events? Will meals still need to be prepared? Is there someone that can take you to the doctor or hospital if necessary?
Stock up on tissues. Have a week's worth of pain/fever-reducing medication on hand for each member in the household. Buy a thermometer.
Get yourself some DVDs and books you can pass the time with while you're lying on the couch or in bed.
Stock up on foods that comfort you when you're not feeling well, such as teas, juices or chicken noodle soup. Remember that you won't be well enough to go.
Stock your freezer with a week's worth of pre-made dinners so you won't have to worry about cooking until you've fully recovered.
Dig out your doctor's phone number and post it on your fridge. You should also add any school or work numbers that you may need to call for any absenteeism.
Buy yourself a nice handsoap and a good hand lotion. You should be washing your hands alot, so may as well pamper them in the process.
Learn the different symptoms for colds and flus and learn what is considered a medical emergency.
How is the new H1N1 treated?
2009 H1N1 flu virus is sensitive to the antiviral drugs Tamiflu and Relenza. These antiviral drugs are most effective when taken within 48 hours of the onset of flu symptoms.
Most people who come down with the new H1N1 flu recover fully without antiviral treatment.
Antiviral treatment is recommended, though, for people in high-risk groups who could suffer from flu complications.
Keep in mind that your doctor will not be able to determine whether you have the new H1N1 flu, but may take a sample and send it to a lab for testing. Because of the testing time, though, you could be fully recovered by the time the results come back. If your doctor suspects it to be the new H1N1 flu, they may also write you a prescription for Tamiflu or Relenza just to be safe.
Flu vaccine
If you have had a flu vaccine this season, it does not mean you are protected against the new H1N1 flu virus. You need to get both a seasonal flu shot as well as a 2009 H1N1 flu shot.
The vaccine should be available to Canadians in November.
It generally takes three weeks for the vaccine to give a person full immunity.
While there will be enough of the vaccine for all Canadians who need and want protection, not everyone can be immunized at the same time. Those that need it most will get it first.
who will be immunized first?
- People under 65 with chronic health conditions
- Pregnant women
- Children 6 months to 5 years old
- People living in remote and isolated settings
- Health care workers involved in pandemic response or the delivery of essential health care services
- Household contacts and care providers of persons at high risk
How long does the flu virus survive on surfaces?
The H1N1 flu virus can live outside the body for:
24-48 hours on hard surfaces such as stainless steel and plastic
8-12 hours on soft surfaces cloth, tissues or paper
But it often only remains infectious for 2-8 hours after being deposited on hard surfaces, and only a few minutes on soft surfaces.
How bad is the new H1N1 flu?
The severity of cases in the current outbreak has varied widely, from mild cases to fatalities. The vast majority of cases have been mild.
Many of the complicated cases have appeared in young people aged 5 to 24. Pregnant women have also been particularly vulnerable to severe flu.
Studies of the virus show that it is more infectious to lung cells than regular seasonal flu viruses. But the new H1N1 flu virus is less well adapted to humans and may be harder to inhale deep into the lungs.
Flu viruses change all the time -- and are notoriously hard to predict. The way this flu virus evolved suggests that it is liable to swap gene segments with other flu viruses. To date, the 2009 H1N1 flu virus has not evolved much since the initial outbreak, which is good news for the vaccine, which is based on H1N1 strains isolated early in the pandemic. Scientist are watching closely to see whether the virus continues to evolve.