Swine Flue

WebMD Provides Answers to Your Questions About Swine Flu
By Miranda Hitti
WebMD Health News
Reviewed by Louise Chang, MD
The swine flu virus in the U.S. is the same one causing a deadly epidemic in Mexico. What is swine flu? What can we do about it? WebMD answers your questions.

• What is swine flu? 
• What are swine flu symptoms? 
• Who is at highest risk of H1N1 swine flu? 
• If I think I have swine flu, what should I do? 
• How does swine flu spread? 
• How is swine flu treated? 
• Is there a vaccine against the new swine flu virus? 
• I had a flu vaccine this season. Am I protected against swine flu? 
• How can I prevent swine flu infection? 
• How long does the flu virus survive on surfaces? 
• Can I still eat pork? 
• What else should I be doing? 
• How severe is swine flu? 
• Why has the swine flu infection been deadlier in Mexico than in other countries? 
• Have there been previous swine flu outbreaks? 
• I was vaccinated against the 1976 swine flu virus. Am I still protected? 
• How many people have swine flu? 
• How serious is the public health threat of a swine flu epidemic? 

What is swine flu?
Like people, pigs can get influenza (flu), but swine flu viruses aren't the same as human flu viruses. Swine flu doesn't often infect people, and the rare human cases that have occurred in the past have mainly affected people who had direct contact with pigs. But the current swine flu outbreak is different. It's caused by a new swine flu virus that has changed in ways that allow it to spread from person to person -- and it's happening among people who haven't had any contact with pigs.

What are swine flu symptoms?

Symptoms of swine flu are like regular flu symptoms and include fever, cough, sore throat, runny nose, body aches, headache, chills, and fatigue. Many people with swine flu have had diarrhea and vomiting. Nearly everyone with flu has at least two of these symptoms. But these symptoms can also be caused by many other conditions. That means that you and your doctor can't know, just based on your symptoms, if you've got swine flu. It takes a lab test to tell whether it's swine flu or some other condition.

Who is at highest risk from H1N1 swine flu?

Most U.S. cases of H1N1 swine flu have been in older children and young adults. It's not clear why, and it's not clear whether this will change.
But certain groups are at particularly high risk of severe disease or bad outcomes if they get the flu:
• Pregnant women 
• Young children, especially those under 12 months of age 
• People with heart disease or risk factors for heart disease 
• People with HIV infection 
• People with chronic diseases 
• People taking immune suppressing drugs, such as cancer chemotherapy or anti-rejection drugs for transplants 
People in these groups should seek medical care as soon as they get flu symptoms.

If I think I have swine flu, what should I do? When should I see my doctor?

If you have flu symptoms, stay home, and when you cough or sneeze, cover your mouth and nose with a tissue. Afterward, throw the tissue in the trash and wash your hands. That will help prevent your flu from spreading.
If you've got flu symptoms, and you live in or recently visited an area where H1N1 swine flu cases have been identified, CDC officials recommend that you see your doctor. If you have flu symptoms but you haven't been in a high-risk area, you can still see a doctor -- that's your call.
Keep in mind that your doctor will not be able to determine whether you have swine flu, but he or she may take a sample from you and send it to a state health department lab for testing to see if it's swine flu. If your doctor suspects swine flu, he or she would be able to write you a prescription for Tamiflu or Relenza. Those drugs aren't a question of life or death for the vast majority of people. Most U.S. swine flu patients have made a full recovery without antiviral drugs.
But there are emergency warning signs.
Children should be given urgent medical attention if they:
• Have fast breathing or trouble breathing
• Have bluish or gray skin color
• Are not drinking enough fluids
• Are not waking up or not interacting
• Are so irritable that the child does not want to be held
• Have flu-like symptoms that improve but then return with fever and a worse cough
• Have fever with a rash
Adults should seek urgent medical attention if they have:
• Difficulty breathing or shortness of breath
• Pain or pressure in the chest or abdomen
• Sudden dizziness
• Confusion
• Severe or persistent vomiting

How does swine flu spread? Is it airborne?

The new swine flu virus apparently spreads just like regular flu. You could pick up germs directly from an infected person, or by touching an object they recently touched, and then touching your eyes, mouth, or nose, delivering their germs for your own infection. That's why you should make washing your hands a habit, even when you're not ill. Infected people can start spreading flu germs up to a day before symptoms start, and for up to seven days after getting sick, according to the CDC.
The swine flu virus can become airborne if you cough or sneeze without covering your nose and mouth, sending germs into the air.
The U.S. residents infected with swine flu virus had no direct contact with pigs. The CDC says it's likely that the infections represent widely separated cycles of human-to-human infections.

How is swine flu treated?

The new swine flu virus is sensitive to the antiviral drugs Tamiflu and Relenza. The CDC recommends those drugs to prevent or treat swine flu; the drugs are most effective when taken within 48 hours of the start of flu symptoms. But not everyone needs those drugs; many of the first people in the U.S. with lab-confirmed swine flu recovered without treatment. The Department of Homeland Security has released 25% of its stockpile of Tamiflu and Relenza to states. Health officials have asked people not to hoard Tamiflu or Relenza.

Is there a vaccine against the new swine flu virus?

No. But the CDC and the World Health Organization are already taking the first steps toward making such a vaccine. That's a lengthy process -- it takes months. 
I had a flu vaccine this season. Am I protected against swine flu?
No. This season's flu vaccine wasn't made with the new swine flu virus in mind; no one saw this virus coming ahead of time. 
If you were vaccinated against flu last fall or winter, that vaccination will go a long way toward protecting you against certain human flu virus strains. But the new swine flu virus is a whole other problem.

How can I prevent swine flu infection?

 The CDC recommends taking these steps:
• Wash your hands regularly with soap and water, especially after coughing or sneezing. Or use an alcohol-based hand cleaner.
• Avoid close contact with sick people.
• Avoid touching your mouth, nose, or eyes. That's not easy to do, so keep those hands clean.
• If you feel ill, stay home.
How long does the flu virus survive on surfaces?
Flu bugs can survive for hours on surfaces. One study showed that flu viruses can live for up to 48 hours on hard, nonporous surfaces such as stainless steel and for up to 12 hours on cloth and tissues. The virus seems to survive only for minutes on your hands -- but that's plenty of time for you to transfer it to your mouth, nose, or eyes.
Can I still eat pork?
Yes. You can't get swine flu by eating pork, bacon, or other foods that come from pigs.

What else should I be doing?

Keep informed of what's going on in your community. Your state and local health departments may have important information if swine flu develops in your area. For instance, parents might want to consider what they would do if their child's school temporarily closed because of flu. Don't panic, but a little planning wouldn't hurt.

How severe is swine flu?

The severity of cases in the current swine flu outbreak has varied widely, from mild cases to fatalities. Early cases in the U.S. were mild, but there has been at least one U.S. death from swine flu. And it's impossible to know whether the virus will change, either becoming more or less dangerous. Scientists are watching closely to see which way the new swine flu virus is heading -- but health experts warn that flu viruses are notoriously hard to predict, as far as how and when they'll change.
But there's a lot of planning you can do. CDC officials predict that just about every U.S. community will have H1N1 swine flu cases. It's possible some schools in your community may temporarily close. So make contingency plans just in case you are affected.

Why has the swine flu infection been more severe in Mexico than in other countries?

That's not clear yet. Researchers around the world are investigating the differences between the cases in Mexico and those elsewhere. 

Have there been previous swine flu oubtreaks?

Yes. There was a swine flu outbreak at Fort Dix, N.J., in 1976 among military recruits. It lasted about a month and then went away as mysteriously as it appeared. As many as 240 people were infected; one died.
The swine flu that spread at Fort Dix was the H1N1 strain. That's the same flu strain that caused the disastrous flu pandemic of 1918-1919, resulting in tens of millions of deaths.
Concern that a new H1N1 pandemic might return in winter 1976 led to a crash program to create a vaccine and vaccinate all Americans against swine flu. That vaccine program ran into all kinds of problems -- not the least of which was public perception that the vaccine caused excessive rates of dangerous reactions. After more than 40 million people were vaccinated, the effort was abandoned.
As it turned out, there was no swine flu epidemic.
Even though it's an H1N1 type A flu bug, the new swine flu is a different virus than the ones that emerged in 1918 and in 1976.

I was vaccinated against the 1976 swine flu virus. Am I still protected?

Probably not. The new swine flu virus is different from the 1976 virus. And it's not clear whether a vaccine given more than 30 years ago would still be effective.

How many people have swine flu?

That's a hard question to answer because the figure is changing so quickly. If you want to keep track of U.S. cases that have been confirmed by lab tests and reported to the CDC, check the CDC's web site. If you're looking for cases in other countries, visit the World Health Organization's web site. And when you hear about large numbers of people who are ill, remember that lab tests may not yet have been done to confirm that they have swine flu. And there may be a little lag time before confirmed cases make it into the official tally.

How serious is the public health threat of a swine flu epidemic?

The U.S. government has declared swine flu to be a public health emergency.
It remains to be seen how severe swine flu will be in the U.S. and elsewhere, but countries worldwide are monitoring the situation closely and preparing for the possibility of a pandemic.
The World Health Organization has not declared swine flu to be a pandemic. The WHO wants to learn more about the virus first and see how severe it is and how deeply it takes root.
But it takes more than a new virus spreading among humans to make a pandemic. The virus has to be able to spread efficiently from one person to another, and transmission has to be sustained over time. In addition, the virus has to spread geographically.
How serious is the public health threat of a swine flu epidemic? continued...
The H1N1 swine flu outbreak comes at the end of the U.S. flu season. The virus has spread across the nation. Nobody knows whether it will stick around all summer or whether it will get worse when flu season begins again this fall.
Scientists are closely watching the Southern Hemisphere to see whether the H1N1 swine flu begins to circulate there. If it does, it will be important to see whether the virus changes over time, and whether it spreads more efficiently in the winter months.
 
WebMD senior writer Daniel J. DeNoon contributed to this report.