Harvard Medical School’s Harvard Health Publication – “Swine Flu” Q and A

Information on the Swine Flu, that can help us all stay safe this Flu season. Please read:

Q: What is “swine flu”?
A: Flu is a disease caused by the influenza virus. Humans, pigs, birds, and other animals all can be infected by influenza viruses. Typically, influenza viruses can infect only one species, so the influenza viruses of humans are different from those of pigs and birds. However, pigs sometimes can be infected not only with pig influenza viruses, but also with human and bird influenza viruses. Then these viruses can swap genes, creating new viruses that have a mix of genes—from human, pig, and bird viruses. That is what has happened with this new swine flu virus, which contains some genes from human, swine, and bird influenza viruses.
Sometimes this swapping of genes changes a virus from one able to infect only pigs or only birds to one that also can infect humans. When that happens, we refer to the illness as “swine flu” or “bird flu.”

Q: Are swine flu or bird flu viruses dangerous?
A: When swine flu or bird flu viruses develop the ability to spread from human to human, they can be very dangerous: they can cause a pandemic, and they can produce severe disease.
One reason that pandemic illness often is more severe than the regular winter flu is that the virus is so new. The regular winter flu viruses that circulate each year are human influenza viruses and are similar to the viruses that have caused the flu in years past. As a result, most people have some degree of immunity to the latest regular human flu virus. The unusual swine flu or bird flu viruses that develop the ability for person-to-person spread are so different from regular human flu viruses that many people have little or no immunity to them. That is what experts think has happened with the new swine flu H1N1 virus.

Q: How contagious will this virus be?
A: So far, this virus appears to be somewhat more contagious than the usual seasonal human flu virus. About a quarter of people who have had close exposure to someone with swine flu have gotten the virus. However, all flu viruses love cold weather: cold, dry air makes flu viruses both more contagious, and more likely to cause serious illness.

Q: How serious is the illness caused by this virus?
A: The normal winter flu kills about one out of 1,000 people who are infected with the virus. In the United States, that amounts to about 35,000 people every year. Early estimates indicate that the new swine flu virus may kill about two out of 1,000 people, about twice as many as normal seasonal flu. However, there is reason to believe that it could cause more severe disease in the late fall and winter of 2009–2010.

Q: How do I know if I’ve caught swine flu?
A: The initial symptoms of this flu virus are like those of the regular flu: fever, muscle aches, runny nose, and sore throat. Nausea, vomiting, and diarrhea may be more common with this swine flu than with the regular flu. If this epidemic hits your community and you develop flu-like symptoms, it is likely your doctor will take samples from your throat or material you cough up for testing.

Q: How do I protect myself?
A: To protect yourself from catching swine flu from others:
Wash your hands or use alcohol-based hand cleaners frequently. For a thorough hand washing, use soap, and scrub all parts of your hands, front and back, and between, for about 20 seconds (about as long as it takes to sing “Happy Birthday”).
Don’t touch your hands to any part of your face: if the virus is on your hands, it can spread to your throat and lungs from your nose and mouth, or even your eyes.
When you greet people, don’t shake hands or exchange kisses. Instead, bump elbows, wave, or just say “Hi.”
Avoid contact with people who are sneezing or coughing. To the extent you can do so, avoid crowded situations. Stay at least three feet away from others.
If you are in public places, remember that when your hands touch what other people’s hands have touched, the virus could be passed to you. For example:
On a bus, don’t hold on to an overhead strap or to a pole. Instead, wrap your arm around the pole to support yourself.
When climbing stairs, don’t hold on to the railing unless you absolutely have to.

Q: How do I protect others if I get sick?
A: If you develop symptoms that could be swine flu, like those mentioned just above, and if your local health department says there is an epidemic in your community, you should pay close attention to the specific advice of the health department. Our general advice is:
Stay at home!
At home, try to stay away from others as much as possible. If you can, try to stay in one room and have others avoid that room. If you have multiple bathrooms, claim one as your own and don’t share it with others.
If you are coughing and sneezing, don’t sneeze into your hands. Instead use tissue and deposit the tissue in a wastebasket or toilet. Wash your hands immediately after.
Don’t shake hands with people, or kiss hello.
If you have to go out, avoid crowded situations—public transportation, movie theaters, and the like.

Q: How long are people contagious?
A: Adults should be considered contagious until at least 7 days after the start of symptoms; with children, it may be 10 to 14 days.

Q: I hear the virus seems to be losing its punch. Is that true?
A: Probably not. The virus did seem to produce more severe disease in Mexico than in the United States and most other parts of the world. But that could be because the weather was getting warmer, and because people in Mexico—not knowing the danger—waited longer to seek medical help. As explained earlier, many experts worry that the virus could produce more severe disease as it spreads in the cold, dry air of fall and winter. That has happened with past pandemics: a summer reprieve was followed by a major outbreak in the fall and winter.
Also, influenza viruses change their genes so frequently that epidemics caused by influenza viruses can change their character quickly. The genetic changes could make the virus cause either more or less serious illness.

Q: Are there vaccines to prevent swine flu?
A: It appears that the first doses of the vaccine will be available in late October 2009. Almost certainly, there will not be enough vaccine for everyone, at first, and so some priority groups will get the vaccine first. In the United States the highest priority groups will be:
Pregnant women because they are at higher risk of complications and can potentially provide protection to infants who cannot be vaccinated.
Household contacts and caregivers for children younger than 6 months of age because younger infants are at higher risk of influenza-related complications and cannot be vaccinated. Vaccination of those in close contact with infants less than 6 months old might help protect infants by “cocooning” them from the virus.
Healthcare and emergency medical services personnel because infections among healthcare workers have been reported and this can be a potential source of infection for vulnerable patients. Also, increased absenteeism in this population could reduce healthcare system capacity.
Children 6 months through 4 years of age, because they are at higher risk of complications
Children 5 through 18 years of age who have chronic medical conditions, because they are at higher risk of complications.
If the vaccine supply is more plentiful, then the CDC recommends vaccinating these same groups plus:
All people from 5 years through 24 years of age
Children from 6 months through 18 years of age because many cases of novel H1N1 influenza occur in children and because children are in close contact with each other in school and day care settings, which increases the likelihood of disease spread, and
Young adults 19 through 24 years of age because many cases of novel H1N1 influenza occur in these healthy young adults, because they often live, work, and study in close proximity, and because they are a mobile population; and,
Persons aged 25 through 64 years who have health conditions associated with higher risk of medical complications from influenza.
Once these people have been vaccinated, then everyone from the ages of 25 through 64 years can begin to be vaccinated. Research shows that the risk for infection among persons age 65 or older is less than the risk for younger age groups, probably because healthy people in this age group are more likely to have some degree of immunity against the virus.

Q: Can you get swine flu from eating pork?
A: Absolutely not. But, as you probably know, you need to cook pork thoroughly to avoid getting other illnesses that can be spread by undercooked meat.For more information on swine flu and influenza, go to Harvard Medical School’s Flu Resource Center at www.health.harvard.edu/flu.

Swine flu symptoms
For adults, teens, and kids aged 3 to 12, the most worrisome symptoms are:
Shortness of breath
Persistent vomiting
Confusion
Dizziness
For children younger than 2, the most worrisome symptoms are:
Very rapid breathing
Not interacting normally, not eating or drinking normally, being unusually irritable, or appearing unusually sleepy
High fever and rash
A bluish color of the lips and skin

Reprinted from Swine flu: How to understand your risk and protect your health, a Special Health Report from Harvard Medical School, © 2009 by Harvard University. All rights reserved.