Swine flu could mix with bird flu, expert warns

Bird flu kills more than 60 percent of its human victims, but doesn't easily pass from person to person. Swine flu can be spread with a sneeze or handshake, but kills only a small fraction of the people it infects.

So what happens if they mix?

This is the scenario that has some scientists worried: The two viruses meet — possibly in Asia, where bird flu is endemic — and combine into a new bug that is both highly contagious and lethal and can spread around the world.

Scientists are unsure how likely this possibility is, but note that the new swine flu strain — a never-before-seen mixture of pig, human and bird viruses — has shown itself to be especially adept at snatching evolutionarily advantageous genetic material from other flu viruses.

"This particular virus seems to have this unique ability to pick up other genes," said leading virologist Dr. Robert Webster, whose team discovered an ancestor of the current flu virus at a North Carolina pig farm in 1998.

The current swine flu strain — known as H1N1 — has sickened more than 2,300 people in 24 countries. While people can catch bird flu from birds, the bird flu virus — H5N1 — does not easily jump from person to person. It has killed at least 258 people worldwide since it began to ravage poultry stocks in Asia in late 2003.

‘Do not drop the ball’

The World Health Organization reported two new human cases of bird flu on Wednesday. One patient is recovering in Egypt, while another died in Vietnam — a reminder that the H5N1 virus is far from gone.

"Do not drop the ball in monitoring H5N1," WHO Director-General Margaret Chan told a meeting of Asia's top health officials in Bangkok on Friday by video link. "We have no idea how H5N1 will behave under the pressure of a pandemic."

Experts have long feared that bird flu could mutate into a form that spreads easily among people. The past three flu pandemics — the 1918 Spanish flu, the 1957-58 Asian flu and the Hong Kong flu of 1968-69 — were all linked to birds, though some scientists believe pigs also played a role in 1918.

Webster, who works at St. Jude's Children's Research Hospital in Memphis, Tenn., said bird flu should be a worry now. Bird flu is endemic in parts of Asia and Africa, and cases of swine flu have already been confirmed in South Korea and Hong Kong.

"My great worry is that when this H1N1 virus gets into the epicenters for H5N1 in Indonesia, Egypt and China, we may have real problems," he told The Associated Press. "We have to watch what's going on very diligently now."

Spokesman Dave Daigle said he could not comment specifically on how concerned the U.S. Centers for Disease Control and Prevention is about the scenario Webster describes, or what it is doing to study such a possibility.

Malik Peiris, a flu expert at Hong Kong University, said the more immediate worry is that swine flu will mix with regular flu viruses, as flu season begins in the Southern Hemisphere. It is unclear what such a combination would produce.

But he said there are indications that scenario is possible. Peiris noted that the swine flu virus jumped from a farmworker in Canada and infected about 220 pigs. The worker and the pigs recovered, but the incident showed how easily the virus can leap to a different species.

"It will get passed back to pigs and then probably go from pigs to humans," Peiris said. "So there would be opportunities for further reassortments to occur with viruses in pigs."

He said so far bird flu hasn't established itself in pigs — but that could change.

"H5N1 itself has not got established in pigs," he said. "If that were to happen and then these two viruses were both established in pigs in Asia, that would be quite a worrying scenario."

No evidence of mixing yet

Michael Osterholm, an infectious disease specialist at the University of Minnesota who has advised the U.S. government on flu preparations, said while flu experts are discussing the scenario, he has yet to see specific evidence causing him to think it will happen.

"Everything with influenza is a huge guessing game because Mother Nature holds all the rules, and we don't even know what they are, so anything's possible," he said. "We don't have any evidence that this particular reassortment is that much more likely to pick up H5N1 than any other reassortment out there."

"We don't have to put these things together," he added. "This is not chocolate and peanut butter running into each other in the dark hallway."

But there is in fact discussion of putting them together — in a high-security laboratory — to see what a combination would look like, according to Webster. Similar tests have been done at the CDC mixing bird flu and seasonal human flu, resulting in a weak product, he said.

Daigle, the CDC spokesman, refused to comment on the prospect of any such experiment.

Infections around the world

Webster has done groundbreaking work on both swine and bird flus in his 40-year career, and has followed the evolution of the current swine flu strain from a virus that sickened a handful of people who worked with North Carolina hogs into a bug that has spread from person to person around the world.

He is closely involved in the global effort to analyze what the virus might do next. It has killed 42 people in Mexico and two in Texas, but so far has not proven very deadly elsewhere, leading to some criticism that the World Health Organization's warnings of a potential pandemic have been overblown.

Webster said underestimating the swine flu virus would be a huge mistake.

"This H1N1 hasn't been overblown. It's a puppy, it's an infant, and it's growing," he said. "This virus has got the whole human population in the world to breed in — it's just happened. What we have to do is to watch it, and it may become a wimp and disappear, or it may become nasty."

source: msn health

H1N1 flu (swine flu): Can you catch it twice?

H1N1 flu (swine flu) can't reinfect you, but it's not the only flu in town.

From MayoClinic.com

No name / No state givenQ: My children are just getting over the swine flu (H1N1), and I may have picked it up. If I get sick, is there a chance the kids will catch swine flu a second time, from me?

After being infected with the 2009 swine flu virus, your children can't catch the same virus again — not from you, not from anyone else. All flu viruses are that way. Once you're exposed to a flu virus, your immune system develops antibodies and memory cells unique to that virus. Your body can then defend itself if you're exposed to the virus again. This system of defense is known as acquired immunity. You also acquire immunity to flu viruses when you get a flu shot or take the nasal flu vaccine.

If having the flu or getting vaccinated gives you immunity, why is the 2009 swine flu (H1N1) virus such a problem? And why get a seasonal flu shot every year?

The short answer: Flu viruses rearrange their DNA all the time; it's how they survive. So, while your children are now immune to influenza caused by the 2009 swine flu virus, other flu viruses can still make them sick, as can many noninfluenza viruses, including those that cause colds and pneumonia.

What you're coming down with is most likely an infection with the same virus your kids had, and most flu-like illness these days is caused by the H1N1 virus. But on the off chance that you have a viral infection your children aren't immune to, it's still wise for everyone in your home to wash their hands often and cover their coughs and sneezes. You don't have to isolate yourself from the rest of the family, but give them some distance until you're well again.

Flu Shots While Pregnant?

Protecting yourself and your fetus from viruses.

By Howard LeWine, M.D., Harvard Health Publications

Pregnant women and those who expect to become pregnant are being urged to get flu shots, especially the vaccine for H1N1 (swine) flu. But that’s not always a simple decision for a woman once she knows she is pregnant. For most, protecting the health of the fetus is their No. 1 concern. This means many of them won't take a medicine or have a medical procedure unless they know that it is absolutely safe for the baby.

A vaccine against the novel H1N1 flu virus is being shipped and has arrived in many states. Its rapid development and production is a terrific achievement. The vaccine will help to protect against the virus commonly called swine flu.

The U.S. Centers for Disease Control and Prevention says that pregnant women should get the vaccine. In fact, they are on the priority list to get the vaccine first.

Pregnancy puts women at increased risk of getting serious health problems if they get seasonal flu. We don't completely understand why this happens. The risk is even higher if they get infected with the H1N1 flu virus. It can even be life-threatening.

This risk probably is higher than usual because most pregnant women have not been exposed to flu strains similar to the new H1N1 virus. So they don't have any natural immunity. Older people, especially those over age 60, do seem to have some natural immunity. This is one of the reasons younger people have a higher priority to get the vaccine.

It is understandable that pregnant women are anxious about choosing to get the swine flu vaccine. The vaccine is too new to give pregnant women assurance that it is 100 percent safe. But the safety of the H1N1 flu shot should be equal to the well established safety of previous flu shots. The swine flu shot, similar to the seasonal flu shot, is made from purified killed virus. There is no chance that you or your baby can get an infection from the vaccine.

Pregnant women should get the H1N1 flu shot and the seasonal flu shot for several reasons:

• They can protect infants who cannot receive vaccination. The mother can pass protective antibodies to her fetus. They may help protect the baby after it's born.
• If you do get the flu, you have a higher than average risk of getting pneumonia. Pneumonia lowers your blood oxygen level. This means your fetus may not receive the oxygen needed for normal development.
• Having the flu in pregnancy increases your risk of a miscarriage or giving birth too early.
• Women who have a fever during early pregnancy are more likely to deliver a baby with a neural tube defect, such as spina bifida.
  

Some people are concerned about thimerosal, a preservative used in many vaccines. The safety of thimerosal has been extensively studied. There is no scientific evidence of any bad effects on babies when mothers get shots containing this preservative.

Pregnant women have an understandable reluctance to getting a shot that has not had thorough testing. Certainly more testing would make all of us feel more secure about its safety. But in balance, I believe the risks of not having the shot are greater than the unlikely, but remotely possible, side effects that have not been seen so far.

From: MSN Health

Your Swine Flu To-Do (and Don’t Do) List

by Theresa Tamkins

Health.com

Swine flu vaccines are rolling out this month—finally. Health-care workers in Indiana and Tennessee were the first to get the nose-spray version, while New Yorkers clamoring for the H1N1 vaccine finally had their chance too.

However, the onslaught of information about H1N1—be it playground rumors, employer signs telling you to cover your cough, memos from your kids’ school, or scary-sounding news reports—is making it pretty hard to figure out what you should be doing right now.

Although some people have already been vaccinated, it could be weeks—depending on your age and risk factors—before you even get a chance at the shot (or spray). So now what?

Sometimes it feels like you have two choices:

Wring your hands endlessly about something over which you have no control.

Tune out the static and pretend this is all just a horrible dream. (Call it the ignore-the-whole-sorry-mess-until-my-neighbor-is-sick approach.)

Well, guess what? There are a few things you should—and should not—be doing at the moment. Here’s your guide.

Look up local flu outbreaks

If you’re getting most of your news from the Internet—and about 40% of people say they do—you may not be up on H1N1 activity in your community. Take the time to check local flu activity on the online version of your local newspaper (remember those?) or health department. Try FluTrends, which is produced by Rhiza Labs, and includes past cases and current activity, or the Centers for Disease Control and Prevention’s (CDC) weekly flu update.

If your city or state is a bit of a hot spot, you may need to focus on some of these to-do points sooner than others. The good news is that some of the hardest hit areas in spring—like New York—don’t seem to have that many H1N1 cases at the moment. (Experts estimate that up to 1 million New Yorkers may have had H1N1 in the spring, which would protect against subsequent infections.)

Don’t panic

For most people, an H1N1 infection is generally mild and can be cured with time, bed rest, and fluids. The virus is serious, though—particularly for those in high-risk groups. So far this year, 28 pregnant women have died of H1N1, as have 76 children. “At least two-thirds of [the children] had underlying conditions, which we recognize as putting them at increased risk for complications,” says Nathan Litman, MD, the chief of pediatric infectious diseases at the Children’s Hospital at Montefiore, in New York City. High-risk people, whether adults or children, tend to have chronic heart or lung conditions (including asthma), weakened immune systems due to disease or chemotherapy treatment, or diabetes.

That said, H1N1 will feel like seasonal flu for most people. “I’d say at the present time the swine flu looks no more serious than the routine seasonal influenza,” says Dr. Litman.

Stay home

Are you sick right now? Say, with flu-like symptoms such as fever, aches, stuffy nose, and chills? Sorry, but it’s quite possible you already have swine flu. Experts say that flu activity is higher-than-normal for this time of year and almost all of it is due to H1N1. If you (or your child) are not in a high-risk group, it’s best to stay put.

If a child is 2 or older "and has no risk factors for complications and has fever, runny nose, or cough, the best thing to do is to stay home,” says Dr. Litman. “Plenty of fluids, Tylenol, Motrin, or Advil for fever, and it should run its course on its own.”

If a child has difficulty breathing, is unable to take fluids, or starts to be less responsive, or after appearing to recover from the influenza develops a fever and starts coughing again, then see a doctor.

If you are pregnant and have flu symptoms, it might be best to call your doctor before going in to see him or her, says Dr. Litman.

“They may want to set up a separate location to be seen or separate times to see sick patients,” he says. “You don’t want the pregnant woman with influenza who is coughing and sneezing to go into the room with pregnant women who are well and just there to get routine prenatal care.”

Understand the risks

While the symptoms of H1N1 may be no different from seasonal flu, there are some key differences. H1NI may be easier to catch than regular flu, and younger people may be more likely to come down with it than older people. “From what I’ve seen, I actually believe it to be more contagious,” says Dr. Litman. Often with the seasonal flu that’s circulating, a percentage of the population has some immunity to it. With H1N1, it looks like most people—other than the elderly—have no immunity to it, and that may be why it appears more contagious, he says.

People who are older than 60 may have been exposed to a swine-flu-like virus in the distant past, which is giving them an edge with this pandemic. That’s not to say they can’t get sick, but “many of them appear to have immunity from a prior infection with a similar virus or cross reactions with a similar virus that help protect them against the swine flu,” says Dr. Litman.

Get a seasonal flu shot

The regular seasonal flu shots are available now, and it makes sense to “get the jab” (as the Brits say). While most flu cases happening right now are caused by H1N1, “in two months or three months it may be the regular seasonal flu and we should be prepared for that,” says Dr. Litman. “Since that vaccine is currently available, I recommend that everyone considered a risk group receive the seasonal flu vaccine.” Seasonal flu can be just as dangerous as H1N1; about 36,000 people die, including about 80 children, of seasonal flu every year.

Get a pneumonia vaccine

What, another shot? For the vaccine wary, this might just feel like one too many pinpricks. However, the pneumonia vaccine, a shot that can help prevent any illness caused by certain types of pneumococcus bacteria, including meningitis and ear infections, may be a good idea too.

The CDC has analyzed H1N1-related deaths and found many people who died had dual infections, including some with pneumococcus. The good news is that if you’re up-to-date on your child’s vaccines, they probably already have it. Approved in 2001 and called Prevnar, it’s routinely given to children.

Another vaccine, Pneumovax, is available for adults, and is recommended for the elderly and those at high risk of infections.

Wash your hands

Just about every expert is chanting a “wash your hands” mantra. And, in fact, washing your hands with soap and water or using an alcohol rub can help. However, when it comes to flu, just keep in mind that hand-washing may fall into the “can’t hurt and may help” category.

Because flu virus can hitch a ride on airborne water droplets, you can inhale the virus and get sick even if you wear gloves 24-7 or scrub-in like a brain surgeon. But again, flu viruses can live on surfaces for up to 48 hours. So, yes, wash up. Plus, good hygiene can protect you from other germs, like pneumococcus, which could make a simple case of flu much worse when added into the mix.

Don’t stock up on face masks or Tamiflu. If you’re the type of person who hoarded cans of soup and bottled water in 1999 just in case the world ended in 2000, it can be tempting to grab a box of surgical masks “just in case.” The CDC and most experts say that’s not a recommended—or a proven way—to prevent infection, although some studies suggest that they can be helpful in homes with a flu-infected family member or when used by hospital workers in place of a N95 respirator.

And while it may seem perfectly harmless to stockpile antiviral drugs, it isn’t. If Tamiflu is gathering dust in your medicine cabinet, then people who truly need it may find the pharmacies are fresh out. And the surest route to a drug-resistant flu virus is having people taking it “just in case” or for symptoms that would go away on their own.

Get a swine flu vaccine—really

Or at least seriously consider it. Lots of people are not crazy about vaccines in general, and fully one-third of parents say they’re going to skip them for their child, according to an AP poll. Understandable. Taking something that could cause side effects, when you feel (or your child feels) perfectly healthy is tough. But keep in mind that if you’re thinking about waiting until swine flu is in full force in your community, it may be too late. It can take several weeks after vaccination before your immune system ramps up to full-protection mode.

If you or your child is perfectly healthy, you can get the nose-spray version, which contains a weakened, but not killed, virus. Unfortunately, if you’re in a high-risk group, you may have to wait a bit for the version with killed virus, which is given in shot form. Those should be available in mid- to late-October.

While mulling over your options, try not to think of large federal agencies as faceless giants trying to impose vaccines on you. In fact, such agencies are staffed by scientists and doctors who are trying to protect the public.

“Each year approximately 30% to 40% of children between 5 and 19 years of age get influenza, that not only keeps them out of school for a few days, but they are also the epicenter of the epidemic—they spread it to household contacts, other school contacts, and high-risk people in the community, like the elderly—their grandparents,” says Dr. Litman. “For their benefit and for the benefit of others, it’s wise to get both the seasonal flu vaccine and swine flu vaccine.”

Don’t let the past haunt you

Although the 2009 virus has been tagged with the unfortunate moniker swine flu (just like the 1976 version), there is a world of difference between the two. For one, they are different viruses. And if you were alive in 1976, you were probably digging the bicentennial, groovy pants, and platform shoes, but your chances of getting swine flu were pretty much nil. (There were roughly 200 cases in Fort Dix, N.J., and the virus never spread.)

Fast forward to 2009, which is truly a pandemic—there have been more than 340,000 confirmed cases worldwide and nearly 44,000 confirmed and probable cases in the U.S. alone. (The CDC estimates that more than 1 million people have contracted swine flu, but that their cases weren’t recorded because they didn’t seek treatment.) And the ’76 version did have a problem with side effects, including Guillain-Barré syndrome (GBS), a rare condition in which the immune system attacks nerves, resulting in weakness and even paralysis (although most people eventually recover).

However, the vaccine production used in the 1970s now looks as outdated as your striped bell-bottoms and rockin’ sideburns.

“Over the years there have been several improvements in vaccine manufacturing,” says Claudia Vellozzi, MD, the assistant director of the CDC’s Immunization Safety Office. “That certainly plays a role in improved vaccine safety now, compared to 1976.”

Of the 30 to 40 million people vaccinated for swine flu in 1976, about 1 in 100,000 did develop GBS. However, current research suggests there is little to no GBS risk associated with seasonal flu vaccine.

"There have been one or two studies that showed that if there is a risk, it’s very small, or about one in 1,000,000 additional cases of GBS would be attributable to the flu vaccine—but most studies have not supported any association,” she says. (There are 2,000 to 3,000 GBS cases in the U.S. every year, unrelated to vaccines, says Dr. Vellozzi. The cause is unknown, but it can be triggered by infections.)

“In terms of our current vaccine, we expect to have a similar safety profile as our seasonal flu vaccine, which has a good track record,” she says.

Be prepared

If you do want to get an H1N1 flu shot, it’s best to be patient. It may take weeks before everyone who wants one can get it. In the meantime, think about what you will do if you or a family member does get sick.

“Get immunized, wash your hands, cover your mouth and nose if you’re sneezing or coughing, stay home if you’re sick, and if any warning signs come up—difficulty breathing, not responsive as usual, unable to take fluids, or after a day or two of the fever coming down and having more fever and cough again—see the doctor,” says Dr. Litman.

Swine Flu

Swine influenza virus (SIV) is caused by Orthomyxoviruses that are endemic to pig populations. SIV strains isolated to date have been classified either as Influenzavirus C or one of the various subtypes of the genus Influenzavirus A.

Swine flu, unlike bird flu, is able to pass from human to human contact. The 2009 swine flu outbreak is the spread of a new strain of H1N1 influenza virus that was first detected by public health agencies in March 2009. Local outbreaks of influenza-like illness were detected in three areas of Mexico, but the presence of this new strain was not discovered for a month.

Following this discovery in the parts of United States bordering Mexico, its presence was swiftly confirmed in the local outbreaks in Mexico, and in isolated cases elsewhere. By April 27, the new strain was confirmed also in Canada, Spain, and the United Kingdom and suspected in many other nations, with over 1,800 candidate cases.

The new strain is an apparent reassortment of several strains of influenza A virus subtype H1N1, including a strain endemic in humans and two strains endemic in pigs, as well as an avian influenza.

Reassortment is common in influenza viruses, due to the structure of their genome. This particular reassortment is consistent with a transmission of swine influenza from pig to human combined with the mixing of two viral infections in the same person.

In April both the World Health Organization (WHO) and the United States Centers for Disease Control and Prevention (CDC) expressed serious concerns about this novel strain, because it apparently transmits from human to human, has had a relatively high mortality rate in Mexico, and because it has the potential to become a flu pandemic.

On April 25, 2009, the WHO determined the situation to be a formal “public health emergency of international concern”, with knowledge lacking in regard to “the clinical features, epidemiology, and virology of reported cases and the appropriate responses”.

Government health agencies around the world also expressed concerns over the outbreak and are monitoring the situation closely.

Recommendations to prevent infection by the virus consist of the standard personal precautions against influenza. This includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public. People should avoid touching their mouth, nose or eyes with their hands unless they've washed their hands. If people do cough, they should either cough into a tissue and throw it in the garbage immediately or, if they cough in their hand, they should wash their hands immediately.

Many countries confirmed that inbound international passengers will be screened. Typical airport health screening involves asking passengers which countries they have visited and checking whether they feel or look particularly unwell.

On April 27, the CDC recommended the use of Tamiflu and Relenza for both treatment and prevention of the new strain.

Some physicians in the US are recommending the use of masks when in public. The purpose of a face mask is to effectively cover a person’s mouth and nose so that if a person is around someone who is infected, there is a decreased likelihood of transmission.

Cases by country
Country	Laboratory confirmed cases	Other possible cases*	Attributed deaths‡	Refs.
Mexico (details)	26	1,995	149 (20)	[1][2]
United States (details)	48	212+	0	[3][2][4]
Canada (details)	6	28+	0	[2][5]
United Kingdom (details)	2	21	0	[6]
Spain (details)	1	35	0	[7][8]
New Zealand	0	56	0	[9]
Australia	0	19	0	[10][11]
Colombia	0	12	0	[12]
Brazil	0	11	0	[13][14]
Switzerland	0	5	0	[15]
Denmark	0	4	0	[16]
Ireland	0	4	0	[17]
Czech Republic	0	3	0	[18]
Poland	0	3	0	[19]
France	0	3	0	[20]
Guatemala	0	3	0	[21]
Israel	0	2	0	[22]
Argentina	0	1	0	[23]
Costa Rica	0	1	0	[24]
Peru	0	1	0	[25]
Russia	0	1	0	[26]
South Korea	0	1	0	[27]
Totals	83	2,443+	149 (20)
* Not all cases have been confirmed as being due to this strain. Possible cases are cases of influenza-like illness (ILI) that have not been confirmed through testing to be due to this strain. ‡ Deaths with confirmed presence of virus in parentheses.

Questions and answers about swine flu

Mexico is contending with an outbreak of swine flu, suspected in the deaths of dozens of people and sickening perhaps 1,000. In the United States, at least eight cases have been confirmed with the infection, all of them in California and Texas; only one person was hospitalized. Here are some questions and answers about the illness:


Q. What is swine flu?

A. Swine flu is a respiratory illness in pigs caused by a virus. The swine flu virus routinely causes outbreaks in pigs but doesn’t usually kill many of them.

Q. Can people get swine flu?

A. Swine flu viruses don’t usually infect humans. There have been occasional cases, usually among people who’ve had direct contact with infected pigs, such as farm workers. “We’ve seen swine influenza in humans over the past several years, and in most cases, it’s come from direct pig contact. This seems to be different,” said Dr. Arnold Monto, a flu expert with the University of Michigan.

Q. Can it spread among humans?

A. There have been cases of the virus spreading from human to human, probably in the same way as seasonal flu, through coughing and sneezing by infected people.

Q. What are the symptoms of swine flu?

A. The symptoms are similar to those of regular flu — fever, cough, fatigue, lack of appetite.

Q. Is the same swine flu virus making people sick in Mexico and the U.S.?

A. The Centers for Disease Control and Prevention said the Mexican virus samples match the U.S. virus. The virus is a mix of human virus, bird virus from North America and pig viruses from North America, Europe and Asia.

Q. Are there drugs to treat swine flu in humans?

A. There are four different drugs approved in the U.S. to treat the flu, but the new virus has shown resistance to the two oldest. If you suspects any symptoms of Swine flu, contact your physician.

Q. Does a regular flu shot protect against swine flu?

A. The seasonal flu vaccine used in the U.S. this year won’t likely provide protection against the latest swine flu virus. There is a swine flu vaccine for pigs but not for humans.

Q. Should residents of California or Texas do anything special?

A. The CDC recommends routine precautions to prevent the spread of infectious diseases: wash your hands often, cover your nose and mouth when you cough or sneeze, avoid close contact with sick people. If you are sick, stay at home and limit contact with others.

Q. What about traveling to Mexico?

A. The CDC has not warned Americans against traveling to Mexico but advises that they be aware of the illnesses there and take precautions to protect against infections, like washing their hands.

Swine Flu Symptoms