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Showing posts with label vaccine. Show all posts
Showing posts with label vaccine. Show all posts

Wednesday, May 22, 2013

Special Report: How vaccine scares cast shadows over science

By Kate Kelland, Health and Science Correspondent

HELSINKI (Reuters) - At a Finnish medical convention in January 2011, a colleague approached neurologist Markku Partinen, laid a hand on his shoulder and said: "Markku, it's going to be a bad year for you."

In the following months, other scientists ridiculed him, questioned his methods and motives, and raised doubts about his mental stability. Colleagues began crossing the street to avoid him, he says.

Partinen, director of the Helsinki Sleep Clinic and Research Centre, had raised the alarm about a GlaxoSmithKline vaccine called Pandemrix. He had discovered the drug, used to protect people from H1N1 swine flu, may be linked to a jump in cases of narcolepsy, a rare sleep disorder, in children and young people. He knew his findings might help limit the risks of narcolepsy for other children around the world, but was fearful nonetheless. The work was bound to generate scientific suspicion and public anxiety. Indeed, he struggled to get his paper on the vaccine published.

His story underscores an increasingly tough challenge for scientists balancing compelling data with public concern over vaccines and their side effects. Treatments which stimulate immunity to disease are highly controversial. In the past couple of decades - especially after a British doctor made now-discredited claims linking the measles-mumps-rubella (MMR) vaccine to autism - the field has become even more charged. After the false alarm sounded by British doctor Andrew Wakefield, some scientists say they are more hesitant to credit reports of potential side effects from vaccines.

Wakefield's 1998 paper suggesting a link between the MMR vaccine and autism was debunked after repeated scientific studies found no such connection, and was retracted by The Lancet medical journal in 2010. In that year, Wakefield was also struck off Britain's medical register by the General Medical Council for repeatedly breaching "fundamental principles" of research medicine, and he is no longer licensed to work in the UK as a doctor. But he still has thousands of passionate followers, especially in the United States, who question the use of any vaccine and applaud any new evidence that vaccines have unintended consequences.

"Wakefield has done so much damage. We've seen it with all these anti-vaccine people, and now we also see the damage he has done to science," Partinen said.

Partinen's findings have now been replicated and confirmed by at least four independent teams of international scientists. Studies in Sweden, Finland, Ireland, Norway and Britain have also shown the risk of developing narcolepsy is between seven and 13 times higher in children who were immunized with Pandemrix than in those who were not. European drug regulators have recommended the vaccine no longer be used in anyone under 20.

GlaxoSmithKline acknowledges the statistical association, but alongside many more research teams around the world, the company is investigating what might cause the link.

Emmanuel Mignot, a psychiatrist and narcolepsy expert at Stanford University in the United States, is being funded by GSK to investigate further. He says scientists now face a dilemma: even when you publish sound scientific findings, you could attract criticism "like Wakefield", he says.

"And at the same time, I really feel strongly that there's nothing worse than to suppress information - that's how you create paranoia in the public."

Wakefield, who now lives in Austin, Texas, told Reuters he stands by his 1998 Lancet paper. He also says he was the subject of "false allegations" in a subsequent investigation by the British Medical Journal and denies his research was fraudulent. A defamation lawsuit he took out in Texas against the British Medical Journal, its editor Fiona Godlee and writer Brian Deer was dismissed last year when the court said it did not have jurisdiction. Wakefield is appealing that decision.

Godlee said Deer and the BMJ stand by their reporting and their editorial commentary on the Wakefield case "and we believe that Dr. Wakefield's claims are meritless." She described his latest legal challenge as "frivolous" and "yet another instance of him trying to use litigation to harass and silence his critics."

ANTI-VAXXERS

Vaccines have been controversial almost since they were invented in the late 18th century. When British physician Edward Jenner showed he could protect children from smallpox if he infected them with cowpox, the objectors included clergy who believed vaccination was not Christian because it came from an animal.

Today, most doctors and scientists view the technique as one of the greatest breakthroughs in modern medicine. No other medical intervention has done more to save lives and fight disease.

Yet over the past couple of decades, a growing number of people have again become suspicious. The MMR scare "created a sense of fear of vaccines that has extended well beyond autism to a general fear that we're just giving too many vaccines too soon," says Paul Offit, an American pediatrician and vaccine scientist who blasted Wakefield in his book, "Autism's False Prophets."

Wakefield's dedicated following in the anti-vaccination movement - "anti-vaxxers" for short - believe all vaccines are dangerous and should be avoided. For example, Idaho-based group Vaccination Liberation declares on its website that "vaccines are toxic" and that there is no proof vaccinations are safe or effective. It says Wakefield was subjected to a "chain of persecution" and a "witch hunt."

Partinen rejects any comparison between himself and the man who sparked the MMR-autism scandal, calling Wakefield a "fake".

At a medical center on the outskirts of Helsinki, another Finnish scientist agrees with Partinen's results and is probing the mechanics of the Pandemrix-narcolepsy link, which she thinks may have to do with the vaccine's super-charging effect on the immune system.

Outi Vaarala previously worked in research on autoimmune diseases and diabetes. Since crossing over into the field of vaccinology, she says she has found herself harangued in emails and phone calls by people on one side accusing her of undermining trust in vaccines, or on the other begging her to join an anti-vaccine crusade.

"There's not the kind of open discussion we used to have. You're afraid you will lose your whole career if you say something bad," says Vaarala. "When you're dealing with vaccine it suddenly becomes like working in politics, or religion."

"SERVES YOU RIGHT"

For the parents of Swedish teenager Emelie Olsson, the row over vaccines complicates their struggle to come to terms with all that has happened to their family in the past few years.

Emelie is one of at least 800 people across Europe who developed narcolepsy, an incurable, life-long sleep disorder, after having the Pandemrix shot. In total, 30 million doses of the shot were given to people in 47 countries during the 2009/2010 H1N1 swine flu pandemic. It was not used in the United States.

An engaging 14-year-old, Emelie used to enjoy singing in a choir, taking tennis lessons, playing piano and kicking about with her friends. She now struggles to stay awake during the day and battles with terrors and hallucinations that deprive her of sleep and make her scream out in the night.

Her parents, Marie and Charles, still believe children should be vaccinated against diseases that put their lives at risk. The anti-vaccination movement denounces their views.

A blog post on the website "CureZone", which says it is dedicated to "educating instead of medicating", seeks to use Emelie's story as a "cautionary tale" against all flu vaccines. "Don't be fooled. Don't be brainwashed," says the post, by a blogger named "befurther". "Don't end up like Emelie and her parents."

Charles Olsson says some anti-vaccine campaigners have told him in comments online that he is to blame for Emelie's condition because he should not have allowed her to have the flu vaccine. "They even tell you: 'It serves you right,'" he said in their Stockholm apartment on a dark and snowy winter's afternoon.

He cites one post in Swedish on a Facebook page about vaccination where he was discussing what had happened to Emelie. A contributor called Peter W wrote: "Everyone is directly responsible for the vaccines that they take, parents as well, when recommending shooting poison into their newborn babies."

Marie says it feels uncomfortable that "we, people who are in favor of vaccines, have almost become marketing tools for the anti-vaccine movement."

BALANCING RISKS

Offit, the American pediatrician, says one reason the vaccine debate is so polarized is that people find it hard to balance risks. He helped invent a shot against rotavirus, a diarrheal disease that kills hundreds of thousands of children a year in poor countries.

Even at his state-of-the-art Children's Hospital of Philadelphia, he sees children die of diseases that could be prevented through immunization.

During the 2009/2010 pandemic, he saw five children die of H1N1 flu and saw parents baffled and crushed with grief.

"All those children's parents had chosen not to vaccinate them, and all of them said, 'I can't believe this happened to me,'" he told Reuters. "Vaccines are medical products. They have a benefit and - like any product that has a benefit - they could also have a risk. But from the public's standpoint it's difficult. For them, any risk is a bad thing."

Offit says he's had hate mail and death threats, and needed an armed guard at meetings at the CDC during the years he has spent arguing against the anti-vaccination movement.

Vaccination rates, which fell after the MMR scare, have now recovered. But millions of children were unvaccinated, which scientists say explains why some diseases that were nearly eradicated in wealthy countries have rebounded.

Last year, the U.S. Centers for Disease Control and Prevention (CDC) reported an outbreak of whooping cough in the United States that was the most severe in more than half a century.

Hitting an 18-year high, there were 2,016 cases of measles in England and Wales in 2012, according to the UK Health Protection Agency, the highest annual total since 1994.

BIG PROBLEMS

Partinen attended another Helsinki medical conference last month, two years after he had been warned about difficult times ahead. But this time he was leading the first Nordic Symposium on Narcolepsy and its links to the H1N1 swine flu vaccine.

"When we found this, we wanted to publish our results and spread the news to the world because we knew Pandemrix was also being used in other countries," he said. "But there were big problems."

Having double- and triple-checked his findings, Partinen approached the New England Journal of Medicine, one of the world's most respected medical journals, and submitted his study for publication. He says the journal asked for several revisions to the paper, then finally declined to accept it.

"After that we sent it to The Lancet," he said, stressing that this was the same journal which published the now discredited Wakefield paper.

While it is not unusual for such high-level medical journals to reject many papers, Partinen said he was shocked by the strength of The Lancet's resistance to his.

"It was quite exceptional, they asked for revision and revision and revision," Partinen said. "Then they said they'd made an editorial decision - that they couldn't publish it because we didn't know the (biological) mechanism (behind the link between narcolepsy and Pandemrix)."

Partinen argues that scientists don't know the biological mechanisms behind a whole host of diseases - multiple sclerosis and diabetes to name just two - yet The Lancet is full of peer-reviewed papers about those.

Neither The Lancet nor the New England Medical Journal would comment on their editorial decisions.

By the time Partinen's study was published - March 2012, in the open-access journal of the Public Library of Science, PLoS One - many more scientists had replicated his findings, the H1N1 flu pandemic that Pandemrix was designed to protect against had been declared over, and the vaccine's use had been restricted.

For those with narcolepsy it was already too late.

"There is no doubt any more that there is a link," Partinen said. "But it's taken three years to get here."

(This story has been refiled to add a dropped word in the first paragraph)

(Edited by Simon Robinson and Sara Ledwith)


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Wednesday, May 1, 2013

UK scientists develop safer foot-and-mouth vaccine

By Ben Hirschler

LONDON (Reuters) - British scientists have developed a new vaccine against foot-and-mouth disease that is safer and easier to manufacture, an advance they believe should greatly increase production capacity and reduce costs.

The technology behind the livestock product might also be applied to make improved human vaccines to protect against similar viruses, including polio.

The new vaccine does not require live virus in its production - an important consideration as foot-and-mouth disease (FMD) is extremely infectious and vaccine facilities handling virus samples are difficult to secure.

"It spreads like wild fire," said David Stuart, a professor of biology at the University of Oxford, who led the research.

A 2007 outbreak of FMD in southeast England, for example, was traced to a nearby vaccine site. The same facility, ironically, is home to some of the researchers behind the new vaccine.

In contrast to standard FMD livestock vaccines, the new product is made from synthetic empty protein shells containing no infectious viral genome, scientists reported in the journal PLOS Pathogens on Wednesday.

This means the vaccine can be produced without expensive biosecurity and does not need to be kept refrigerated.

"One of the big advantages is that since it is not derived from live virus, the production facility requires no special containment," Stuart said.

"One could imagine local plants being set up in large parts of the world where foot and mouth is endemic and where it still remains a huge problem."

Worldwide, between 3 billion and 4 billion doses of FMD vaccine are administered every year but there are shortages in many parts of Asia and Africa were the disease is a serious problem.

Current standard vaccines are based on 50-year-old technology, although U.S. biotech company GenVec last year won U.S. approval for a new one.

The purely synthetic British vaccine has so far been tested in small-scale cattle trials and found to be effective.

Stuart said the research team from the universities of Oxford and Reading and two state-funded bodies - Diamond Light Source and the Pirbright Institute - would now conduct larger tests while discussing the vaccine's commercial development.

"We are talking to a potential commercial partner," Stuart told Reuters, adding that it would probably take around six years to bring the new vaccine to market. He said it was too early to give an indication of how much the vaccine would cost.

He declined to name the company involved but said it was not Merial, the animal health division of Sanofi that shares Pirbright's site in southeast England.

Stuart and his colleagues were able to produce empty protein shells to imitate the protein coat that surrounds the FMD virus using Diamond's X-ray system to visualize images a billion times smaller than a pinhead.

The same approach could in future be used to make empty shell vaccines against related viruses such as polio and hand-foot-and-mouth, a human disease that mainly affects infants and children, the researchers said.

(Editing by Keiron Henderson)


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Monday, June 27, 2011

Scientists develop new approach for cancer vaccine

By Kate Kelland

LONDON | Mon Jun 20, 2011 10:35am EDT

LONDON (Reuters) - Scientists have developed a technique that uses a library of DNA taken from organs in which tumors can form and harnesses the body's immune response to create a vaccine designed to treat cancer.

In a study published in the journal Nature Medicine on Sunday, researchers from Britain and the United States said that in early tests in mice with prostate cancer, their experimental vaccine was able to shrink tumors, suggesting it could be developed in the future into a treatment for cancer patients.

"Using the immune system to treat cancer is a very exciting area at the moment," Alan Melcher of Leeds University, who co-led the study, said in an interview. "What we've done is to develop a new approach which builds on a promising foundation."

He said the method could potentially be used against other forms of cancer such as skin or breast cancer, but added that the research was at an early stage and it would be several years before a vaccine could be developed for testing in humans.

Immunotherapy treatments -- medicines that enlist the help of the body's immune system to fight disease -- are a relatively new form of potential cancer treatment.

An immunotherapy drug called ipilimumab, or Yervoy, made by Bristol-Myers Squibb, was approved by the U.S. Food and Drug Administration (FDA) in March as the first drug to help advanced melanoma patients live longer.

And last April, the FDA approved Dendreon Corp's Provenge, a therapeutic vaccine designed to stimulate the immune system to attack prostate cancer.

CELLS

Unlike traditional vaccines, therapeutic vaccines are not designed to prevent disease, but to treat it. They contain genes to stimulate the immune system to produce proteins called antigens, which activate the immune system to kill cancer cells.

Several drugmakers are trying to develop cancer vaccines but the work is proving difficult because each tumor has specific proteins and identifying the right antigens is tricky. There are also concerns that if more genes are used to increase the chances of producing successful antigens, this might trigger an immune response that is too strong for the body to handle.

Working with scientists from the Mayo Clinic in Rochester, Minnesota, Melcher's team made a vaccine made from a virus which they genetically engineered to contain a "library" of DNA including multiple fragments of genes -- and therefore many possible antigens.

They found that this approach did not send the immune system into overdrive. Instead, the range of DNA meant the vaccine was able to target the tumor through many routes, they said.

Importantly, the DNA library was harvested from the same organ as the tumor, Melcher explained. This meant that the immune system "self-selected" the cancer antigens to respond to and did not react against other healthy parts of the body.

"The biggest challenge in immunology is developing antigens that can target the tumor without causing harm elsewhere," he said. "By using DNA from the same part of the body as the tumor ... we may be able to solve that problem."

Melcher said his team now planned to develop the technique further and have an experimental vaccine ready for testing in humans within a few years.

SOURCE: bit.ly/kXu1yI Nature Medicine, online June 19, 2011.


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