Dec. 3, 2003 -- Fujian flu is here. Will flu vaccine protect you?
That depends on what you mean by "protect." The CDC says flu vaccine will offer "some" immunity against the Fujian flu that's going around this year. Some people are expected to get the flu even though they got vaccinated. But they won't get as sick as those who didn't get the vaccine.
Fujian flu is what scientists call a "drift variant." It's nearly the same virus as the Panama flu included in this year's vaccine. But it's not exactly the same, notes Jennifer Wright, DVM, an officer in the epidemic intelligence service at the flu branch of the CDC.
"We just don't really know how well the vaccine will protect against the Fujian variant," Wright tells WebMD. "In the past, where a drift variant didn't match the vaccine strain exactly, some vaccinated people didn't get sick, and those who did, had a milder illness. We'll be looking to see if that's true this year."
It would be great if scientists could look at a virus and guess how bad it would be. That's just what the CDC is doing. And "guess" is a big part of it. "We're doing tests on Fujian viruses coming from infected people," Wright says. "Those tests are showing protection in laboratory studies. But we don't know how that translates into a living human body."
Drift and Shift
The Fujian flu is one kind of new flu virus. If you've got to have a new flu, this kind -- a drift variant -- is probably the best kind. Drift variants arise when a lot of people become immune to a circulating flu virus. They're just different enough to be able to spread more than their parent strain. But a drift variant is nothing compared to a shift variant. Shift variants are flu bugs that have managed to change one or both of their two kinds of surface molecules. This lets them entirely escape any immunity because of prior vaccination or infection, says Harry L. Keyserling, MD, director of pediatric
infectious diseases at Emory University in Atlanta.
"Antigenic shift that occurs when there is a new virus derived from animal strains," Keyserling tells WebMD. "That's what resulted in the swine flu pandemic of 1918 and the 1957, 1968, and 1977 influenza pandemics."
Shift variants aren't always as bad as feared. The swine flu scare of 1976 happened because a shift variant looked like the reappearance of the horribly deadly 1918 swine flu. Despite the failure of a mass vaccination effort, this shift variant never broke out as an epidemic. Instead, a drift variant called type A Victoria caused much more illness and death in the 1976-1977 flu season.
Why No Fujian Vaccine?
The Fujian flu outbreak in the U.S. this year isn't totally unexpected. By last June, the virus was spreading during Australia's flu season. Unfortunately, that's not enough warning for vaccine makers.
"The vaccine strains have to be selected about six months in advance of flu season," Wright says. "A WHO committee met in February to decide on the Northern Hemisphere vaccine. Australia didn't have its flu season until summer, when our vaccine already was in production. And just because a drift variant is in Australia is no guarantee it will show up here."
Flu vaccines are weakened viruses grown in eggs and then processed. Each egg can grow only two doses of vaccine. We're talking millions and millions of eggs here -- and lots of human effort to make the viruses into flu shots and flu nasal sprays.
"It takes months just to get all the vaccine viruses grown," Wright notes.
Tips on Protection
Wright and Keyserling agree that there's simply no way to tell how dangerous this year's Fujian flu outbreak is going to be. But the early signs aren't good: An early start to the season, and already several child deaths in the western U.S.
The good news is that it's not too late to get vaccinated. The vaccine takes about two weeks to work -- but flu season lasts until April.
Because the vaccine may not totally protect against infection, some people may need extra precautions -- even if they've had their flu vaccine. Wright says these high-risk people include:
People over 65.
Residents of nursing homes or chronic-care facilities.
People with lung or heart problems -- including people with asthma.
People with diabetes.
People with kidney problems.
Children 6 months to 18 years old who require long-term aspirin treatment.
Women in their second or third trimester of pregnancy.
If exposed to someone with the flu, Wright says these people should see a doctor right away. Doctors can prescribe antiviral drugs that -- if given soon after exposure -- can prevent the flu or make it milder.
Flu Vaccine's Strength Worries Experts
Health Experts Worry That Flu Shots Taken by Millions of Americans
Will Offer Weaker Protection
The Associated Press
Dec. 9 — As flu sweeps across the country, many health experts are worried that the shots taken by tens of millions of Americans will offer considerably weaker protection than any flu vaccine in recent years. The flu shot available this year was formulated to protect against three strains of the virus. But the strain actually circulating this year is somewhat different from those three, and it is probably too late to develop a new formula.
Even though one of the three is a close cousin of this season's bug, whether that will be enough to help people ward off the flu is simply unknown. Some experts expect the level of protection to be 50 percent or less.
Most agree the vaccine will do at least some good. But the word "some" is about specific as scientists at the Centers for Disease Control and Prevention are willing to get. Even in the best of years, the flu shot is not foolproof. Ordinarily it is between 70 percent and 90 percent effective in healthy young adults and somewhat less effective in the elderly. The last time the vaccine missed the mark was in 1997, when a strain called A-Sydney appeared that was significantly different from the strain included in the flu shot. Doctors are still uncertain about how much good the shot did that season, although the CDC estimates it was 30 percent to 50 percent protective.
Scientists say this year's mismatch does not seem to be as great as it was six years ago, but they cannot say with certainty how well the flu shot will work, or even whether it will. "With a vaccine with a less optimal match, you have to say it might not work at all," said Dr. Scott Harper, a CDC epidemiologist. "That's very unlikely. Probably it will not be 90 percent effective. But we just have no good sense of how it will work in humans. Biology is messy."
The mismatch occurred when experts decided to include a strain called A-Panama in this year's shot, the same as last year. It turns out that the dominant virus this fall has been A-Fujian, which has two genetic mutations that make it different. A variety of studies using ferrets, the primary lab animal for flu experiments, and human blood suggest that the A-Panama shots should offer at least partial protection against A-Fujian. The most encouraging predictions come from the World Health Organization, which, along with the U.S. Food and Drug Administration, decides what strains of flu virus will be included in the shot.
Dr. Klaus Stohr said blood taken from people who got this year's shot shows they have 41 percent fewer antibodies against A-Fujian than they do against A-Panama, and three-quarters of vaccinated adults have enough antibodies to protect against A-Fujian. "The data indicate that the vaccine in use does protect to a good extent against the currently circulating strain," Stohr said. However, Harper said human blood samples and ferret experiments cannot be reliably used to predict how well a vaccine will work. The CDC is doing several studies to estimate how well people are protected in areas where the flu is circulating, but the answer probably will not be known until the end of the flu season.
Dr. Walt Orenstein, director of the CDC's National Immunization Program, said it is probably too late to create an additional vaccine for this season, although manufacturers are working with the A-Fujian strain. "I won't rule it out, but it's unlikely," he said. Meanwhile, doctors continue to urge people to get vaccinated, even though supplies are running short, because the vaccine may help make the flu less severe, even if it fails to give complete protection. It also protects against two other flu strains that could appear later in the season.
Dr. Sandra Kemmerly, associate head of infectious diseases at the Oschner Clinic in New Orleans, said there is already anecdotal evidence that the shots are helping people escape the worst of the flu. "Of the people we are seeing who were vaccinated and have flu-like symptoms, it is much milder than if they had not been vaccinated at all," she said.
Dr. Theodore Eickhoff of the University of Colorado, a member of the FDA advisory committee that chose this year's vaccine, estimated it will be less than 50 percent effective at preventing the flu. "It's a guess based on prior years' experience with variant strains," he said. Dr. William Schaffner, head of preventive medicine at Vanderbilt University, noted that even a vaccine that is 50 percent effective may turn a serious illness into a milder one and help protect those who are especially vulnerable, such as the elderly, against pneumonia and death.
"There is no doubt that all of us are concerned," Schaffner said. Doctors said there is circumstantial evidence suggesting that the FluMist nasal spray vaccine, which uses a weakened live virus, may do a better job of protecting against a mismatched virus. Dr. Robert Belshe of St. Louis University said FluMist was tested in children during the season when A-Sydney emerged, and it still appeared to be 86 percent protective. More than 90 percent of children given FluMist that year made antibodies against the new strain, compared with less than a third who received standard flu shots.
This year, manufacturers made 83 million doses of flu vaccine. Supplies ran short in some parts of the country as the early and intense outbreak in Western states increased demand. The CDC said Tuesday it is working to redistribute remaining U.S. supplies and may buy fewer than 500,000 more doses from a British maker. EDITOR'S NOTE: Medical Editor Daniel Q. Haney is a special correspondent for The Associated Press.
Article Date: 18 Apr 2008 - 3:00 PDT
According to the US Centers for Disease Control and Prevention, this year's seasonal flu vaccine has only been 44 per cent effective. And depending on how you look at the effectiveness in the various strains, it would appear overall to be the least effective vaccine for since the 1997-98 flu season when the vaccine effectiveness was essentially zero, the CDC told a press conference.
The 44 per cent effectiveness figure comes from a CDC study whose findings are published in this week's issue of the federal agency's Morbidity and Mortality Weekly Report (MMWR), dated 17th April 2008.The 44 per cent figure is the overall vaccine effectiveness for influenza type A (H3N2), and influenza type B. Type A H3N2 constitutes the majority of the strains circulating so far this year.
When broken down, the effectiveness of the trivalent inactivated vaccine (flu shot) in preventing medically attended laboratory confirmed influenza for type A (H3N2) was found to be 58 per cent, but for type B the effectiveness was found to be zero. So this year, the vaccine has essentially offered no protection against the type B strain.
The study was carried out at the CDC Marshfield clinic in Wisconsin, involving patients enrolled from January 21st to February 8th of 2008 who lived in and around Marshfield, Wisconsin. Dr Dan Jernigan, Deputy Director, CDC Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), briefed reporters in a web conference yesterday.
He said that most of the flu viruses circulating this year have been "less than optimally matched to the viruses in the vaccine". He said the main strains circulating this year were type A H3N2, type A H1N1, and type B. He said that type A H3N2 constituted the majority of the strains circulating this year, and within those, 70 per cent were a series of strains called A-Brisbane10/ 2007.
Jernigan said that while the Brisbane strain had "drifted", it was still "somewhat related" to A-Wisconsin strain, which is in this year's vaccine. Of the type B, over 90 per cent are of the B Florida strain, which belongs to the Yamagada lineage, which is quite different to the Victoria lineage that is in this year's flu vaccine.
The figure of 44 per cent means that the people in the study who received this year's flu shot were 44 per cent less likely to have laboratory diagnosed influenza than those in the study who did not receive the flu shot. This figure is high enough to justify continuing to promote the public health message that people should be vaccinated, said Jernigan. However, he pointed out that because of the less than optimal level of protection offered by the vaccine this year, health professionals and the public need to consider taking what he called the "three pronged approach" to protect against the flu this year.
The "three pronged approach" consists of first, get vaccinated, second take every day precautions such as covering your cough and washing your hands to prevent spreading of germs, and third, take anti-viral drugs, as recommended by your doctor. Jernigan warned that if the B strains become dominant in the rest of this season, health care professionals should be prepared for an increased risk of vaccine failure and consider using anti-virals earlier to treat and prevent illness in people at higher risk of flu complications.
The Wisconsin study mentioned in the MMWR report was based on laboratory data, which is only part of the picture when assessing the effectiveness of the vaccine. Jernigan said the CDC was beginning to get early figures that showed "substantial cross protection against the predominant virus in the United States this season", and this showed that "continuing to promote vaccination is beneficial even when some of the laboratory data might indicate a less than optimum match".
A record number of Americans were vaccinated against the flu this year. Around 113 million doses of flu vaccine were delivered by drug companies in the US this year, more than ever before, and around 10 million more doses than last season, Dr Jeanne Santoli, Deputy Director, CDC Immunization Services Division, NCIRD told the news conference.
At the peak of the season this year, which was around the middle of February, flu deaths peaked to reach 9.1 per cent of all deaths in the US. This is similar to four years ago, when during the 2003-2004 season, flu deaths peaked at 10.4 per cent of all US deaths. The flu epidemic is still ongoing in the US, with six states, Connecticut, Maine, Maryland, New York, Pennsylvania, and Vermont, still experiencing widespread infection. The strains included in a seasonal flu vaccine are decided every year, when world experts get together to anticipate the strains of flu that are likely to circulate the globe in the coming flu season.
But, because of the lead times to produce the hundreds of millions of vaccine doses needed worldwide, it means the experts have to make the decision about the likely strains months before we know which strains will actually be circulating by the time the flu comes around. And during that time the risk is that things can go very differently. Flu viruses mutate and the balance among the strains changes. So there are "good" years, when the vaccine strains match the circulating strains (these are when the match is about 70 per cent effective) and there are bad years, when the match can even be zero for some subtypes.
Depending on how you look at the vaccine's effectiveness, for instance taking just the overall vaccine effectiveness figure, it appears that this year's effectiveness is the lowest since the 1997-1998 season, when overall effectiveness was about 50 per cent. This emerged during a question and answer session between Jernigan and reporters.
"Interim Within-Season Estimate of the Effectiveness of Trivalent Inactivated Influenza Vaccine - Marshfield, Wisconsin, 2007-08 Influenza Season."
Centers for Disease Control and Prevention.
Morbidity and Mortality Weekly Report (MMWR), 17 April 2008.
DECEMBER 16, 2003. The bigger and more insane the lie, the more people will believe it---even after it's obvious it IS a lie.
In the last two days, AP has posted an article on the flu vaccine, explaining how difficult it is to make the right prediction, each season, on which strain of flu to build a vaccine against. Which strain will be the dominant infection in the population, etc. Blah, blah.
Buried in the story is this VERY interesting remark:
"Ten percent to 20 percent of H3N2 viruses around the world were Fujian [this year]. But the Centers for Disease Control and Prevention [CDC] was having trouble isolating a sample that could be the basis of a vaccine."
COULD NOT ISOLATE THE FLU VIRUS.
OBVIOUSLY HAD ALREADY ISOLATED IT ONCE IN ORDER TO DETECT ITS EXISTENCE BUT NOW COULD NOT ISOLATE IT AGAIN.
OR HAD IT EVER BEEN ISOLATED IN THE FIRST PLACE?
OR HAD IT JUST BEEN INFERRED FROM SO-CALLED EVIDENCE?
WHEN THE CHIPS WERE DOWN---TIME TO MAKE A VACCINE---THEY COULD NOT FIND IT.
This goes to the heart of what I have been writing for years about the virus hunters. They are winging it. They have established certain patterns or rituals for discovering new viruses...and they stick to them even though they are not scientific. The more arcane these rituals are, the more other scientists are cowed and refuse to issue challenges.
This is the Boy Who Cried Wolf, over and over. When the townspeople show up, the wolf isn't there.
"Oh the wolf was here, but he isn't now."
"The Fujian virus was here, I know I put it somewhere, but I can't find it." This is sheer blue sky baloney. "I can describe the entire genetic sequence and headlights and the grill and the fins and the color and door handles of this new virus...I just can't get my hands on an actual virus."
Sure. Just go back to your padded cell. We'll call you if we need you.
JON RAPPOPORT www.nomorefakenews.com