Revisiting The Influenza-Parkinson’s Link

 

Influenza Virons – Credit CDC PHIL

 

# 6443

 

We’ve a new study, conducted by the University of British Columbia, that finds a linkage between a past history of severe bouts of influenza and the likelihood of developing Parkinson’s disease later in life.

 

In fact, according to their research, a severe bout of influenza doubles a person’s chances of developing the neurological condition.

 

If all of this sounds vaguely familiar, it may be because we explored the idea of a Parkinson’s-Influenza link back in 2009 (see More On The Influenza-Parkinson’s Link).

 

Interestingly, the UBC researchers found that those who caught red measles as a child were 35% less likely to develop the disabling disease.   

 

The article appears in the journal Movement Disorders, and the abstract may be read at:

 

Association of Parkinson's disease with infections and occupational exposure to possible vectors

M. Anne Harris PhD, Joseph K. Tsui MB, Stephen A. Marion MD, Hui Shen PhD, Kay Teschke PhD

 

While the study is behind a pay wall, we’ve a short press release from the University of British Columbia  with some of the details.  After which I will return with more.

 

Severe flu increases risk of Parkinson's: UBC research

Severe influenza doubles the odds that a person will develop Parkinson's disease later in life, according to University of British Columbia researchers.

 

However, the opposite is true for people who contracted a typical case of red measles as children – they are 35 per cent less likely to develop Parkinson's, a nervous system disorder marked by slowness of movement, shaking, stiffness, and in the later stages, loss of balance.

 

The findings by researchers at UBC's School of Population and Public Health and the Pacific Parkinson's Research Centre, published online this month in the journal Movement Disorders, are based on interviews with 403 Parkinson's patients and 405 healthy people in British Columbia, Canada.

(Continue . . .)

 

 

Were this all the evidence – medical and occupational histories of a fewer than 1,000 people – then this might not be a terribly convincing study. But we’ve plenty of other research that suggest that some strains of influenza may be neurotropic - capable of infecting and damaging brain cells.

 

In 2009 a study appearing in PNAS found that the H5N1 virus was highly neurotropic in lab mice, and in the words of the authors `could initiate CNS disorders of protein aggregation including Parkinson's and Alzheimer's diseases’.

Highly pathogenic H5N1 influenza virus can enter the central nervous system and induce neuroinflammation and neurodegeneration

Haeman Jang, David Boltz, Katharine Sturm-Ramirez, Kennie R. Shepherd, Yun Jiao, Robert Webster and Richard J. Smeyne

 

Providing more analysis of this study, we’ve an article published on the  St. Jude Children’s Research Hospital website, again from 2009.

 

Avian influenza strain primes brain for Parkinson’s disease

At least one strain of the H5N1 avian influenza virus leaves survivors at significantly increased risk for Parkinson’s disease and possibly other neurological problems later in life, according to new research from St. Jude Children’s Research Hospital.

<SNIP>

This avian flu strain does not directly cause Parkinson’s disease, but it does make you more susceptible,” said Richard Smeyne, Ph.D., associate member in St. Jude Developmental Neurobiology. Smeyne is the paper’s senior author.

 

“Around age 40, people start to get a decline in brain cells. Most people die before they lose enough neurons to get Parkinson’s. But we believe this H5N1 infection changes the curve. It makes the brain more sensitive to another hit, possibly involving other environmental toxins,” Smeyne explained.

 

Smeyne noted the work involved a single strain of the H5N1 flu virus, the A/Vietnam/1203/04 strain. The threat posed by other viruses, including the current H1N1 pandemic flu virus, is still being studied.

(Continue . . . )

 

In 2011 a study by Boise State biology professor Troy Rohn  appeared in PLOS ONE , which unexpectedly found immunohistochemical evidence of prior influenza A infection in the post-mortem brain tissues of 12 Parkinson’s patients they tested.

 

Immunolocalization of Influenza A Virus and Markers of Inflammation in the Human Parkinson's Disease Brain

Troy T. Rohn^*, Lindsey W. Catlin

 

 

We’ve seen other (albeit largely anecdotal) evidence to support an  influenza-neurological disorder link, and not just with Parkinson’s Disease.

 

During the 1918 pandemic, and the decade that followed, more than a million people around the world were afflicted by a mysterious neurological disorder called Encephalitis Lethargica (EL), which some researchers believe may have been precipitated by the influenza virus.  

 

Other forms of neurological symptoms were also reported in the years (and decades) following the 1918 pandemic, leading some researchers to question whether or not it might be a part of some long-term sequelae of the virus.

 

Other scientists have linked EL with a post-streptococcal immune response, or believe it was an autoimmune response, and dismiss the link with the 1918 pandemic.  

 

The cause remains a mystery.

 

Last year a study appeared in the Annals of Neurology, that suggests a link between contracting an upper respiratory infection and developing narcolepsy (cite Narcolepsy Onset is Seasonal and Increased Following the H1N1 Pandemic in China).

 

What these researchers found was, that in China, among a largely unvaccinated population, the incidence of Narcolepsy increased dramatically in the spring after the winter flu season.

 

This increase was most pronounced following the emergence of the H1N1 swine flu virus in 2009.

 

Those results are reminiscent of another study we saw in 2010 (see Lancet: The Influenza - Guillain Barré Syndrome Connection) that suggested the risks of developing GBS – another type of autoimmune disease - were far greater following a bout of the flu, than from receiving the flu vaccine.

 

While conclusive proof of a link between severe influenza A infection and the later development of neurological disorders has not yet been produced, the anecdotal evidence continues to mount.

 

All of which should provide additional motivation to get that seasonal flu shot every year, since the evidence suggests that it may be protecting you against something far worse than simply spending a miserable week in bed.

»» Read More

Lancet: Guillain-Barré Syndrome & H1N1 Vaccine In Children

 

Photo Credit – CDC PHIL 

 

# 5928

 

 

We’ve another study – published yesterday in The Lancet- on the safety of the 2009 pandemic vaccine that looked specifically at the development of Guillain Barre Syndrome among pediatric vaccine recipients in the UK.

 

Guillain-Barre Syndrome (GBS) is a neurological disorder that gained notoriety in 1976 after it was linked to an emergency flu vaccine that was rolled out in anticipation of a `swine flu’ pandemic.

 

As it turned out, the feared pandemic never came.

 

But before the campaign was abandoned - among the 40 million people who were vaccinated - around 500 people developed GBS and 25 died.

 

While not all of those cases were likely caused by the vaccine, the incidence of Guillian-Barre Syndrome was  around 1 in every 100,000 vaccinations. Or five times the expected background rate of this disease.

 

I was a young paramedic at the time, and chronicled my part in that bit of influenza history some time ago in Deja Flu, All Over Again. 

 

In the more than 3 decades since that fiasco, there has been little or no evidence of flu shots causing Guillain-Barre Syndrome. 

 

Still, memories of 1976 linger on, and anti-vaccine activists were only too happy to recall the unfortunate events of that year as they repeatedly warned that the `2009 swine flu vaccine was deadlier than the flu’.

 

Of course, the evidence clearly showed otherwise. 

 

Surveillance and reporting systems have not found any unusual pattern of deaths in the United States attributable to the pandemic vaccine, and the oft predicted spike in Guillain-Barré syndrome (GBS) never occurred (see CIDRAP VAERS study finds H1N1 vaccine safety similar to seasonal vaccines').

 

In fact, the VAERS report cited above found 0 deaths they could link to the pandemic Vaccine. Meanwhile, during the same period the CDC estimated that at least 12,000 (mostly younger) Americans died from the flu.

 

The CDC, along with many other public health agencies, have allowed that the flu vaccine might carry with it a very low risk of developing GBS. But most years the incidence is so low (perhaps 1 in 500,000 or 1 in a million) as to be nearly impossible to measure.

 

This from the CDC’s Guillain-Barré syndrome (GBS)  Q&A page.

 

What causes GBS?

Many things can cause GBS; about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS.

People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

 

 

Recent studies have shown that you are many times more likely to develop GBS in the weeks following an influenza infection, than you are after getting the flu vaccine (see Lancet: The Influenza - Guillain Barré Syndrome Connection).

 

The irony here is, that the flu vaccine may turn out to be the best protection against the adverse vaccine effect that people seem to fear the most.

 

Adding a bit more weight to that argument, we’ve a letter published yesterday in The Lancet that looked at children who developed Guillain-Barré syndrome or Fisher's syndrome between September, 2009, and Aug 31, 2010.

 

doi:10.1016/S0140-6736(11)61665-6

Guillain-Barré syndrome and H1N1 influenza vaccine in UK children

Christopher Verity, Lesley Stellitano, Anne Marie Winstone, Nick Andrews , Julia Stowe , Elizabeth Miller

 

During the 12 months of surveillance, 55 children in the UK were diagnosed with GBS or Fisher’s syndrome. 

 

Of those, only 3 had received the pandemic flu shot, and of those, only 1 had received the shot within 6 weeks of developing neurological symptoms – a time frame that could suggest a causal relationship to the shot.

 

Among those same 55 children, 49 showed laboratory or clinical evidence of infection in the 90 days prior to developing symptoms.

 

• 22 had respiratory infections
• 13 had gastroenteritis
• 7 had H1N1 influenza (5 laboratory-confirmed)
• 2 had seasonal influenza (1 laboratory confirmed)
• 2 had Epstein-Barr virus
• 1 had chickenpox
• and 2 had unexplained fevers

 

Which matches pretty close to the CDC GBS FAQ above that states: about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness.

 

The authors conclude by stating:

 

The peak in the number of children with Guillain-Barré syndrome or Fisher's syndrome shortly after the peak of the second wave of H1N1 infection in November, 2009, might reflect this causal association (figure).

 

Given the proven effectiveness of pandemic influenza vaccine used in UK children, the vaccination programme might have had an overall protective effect against Guillain-Barré syndrome.

 

 

Another UK study I highlighted last July (see BMJ: No Substantial Link Between Flu Vaccines And Guillain-Barre Syndrome), similarly found: 

 

“Adjuvanted pandemic influenza A (H1N1) 2009 vaccines did not increase the risk of Guillain-Barré syndrome substantially, if at all.”

 

For more reassuring research on the safety profile of modern flu vaccines, you may wish to revisit the following blogs:

 

Harvard Study Reaffirms Safety Of Flu Vaccine

MJA: Safety Of Flu Shot In Young Children

NEJM: Study On China’s H1N1 Vaccine Safety

Lancet: Immunogenicity and safety Of Adjuvanted Flu Vaccines

 

While no vaccine (or drug) can be said to be 100% safe – and rare but sometimes serious adverse effects have been reported - the preponderance of evidence continues to support the scientific consensus that flu vaccines are very safe and most years, reasonably effective.

»» Read More

BMJ: Another Pandemrix Study To Ponder

 

 

Photo Credit CDC 

 

# 5897

 

Whenever there is a hint or a suggestion that a vaccine might have caused some sort of serious side effect, it invariably becomes big news. 

 

Even when the reports are preliminary, and the evidence less than rock solid, these stories often end up on the front pages of newspapers and quickly become fodder for the anti-vaccination brigade.

 

When more reassuring vaccine studies come out, they rarely get that kind of media play, since it isn’t the sort of thing that sells newspapers. 

 

Case in point:

 

A little over a year ago GSK’s Pandemrix vaccine was associated with a perceived increase in narcolepsy among children and adolescents in Finland. For early coverage of this story, you may wish to revisit Finland Suspends Use of Pandemrix Vaccine and EMA To Review Pandemrix Vaccine, both of which I wrote in August of 2010.

 

Despite some conflicting and incomplete data the European Medicines Agency issued a statement last July recommending:

 

In persons under 20 years of age Pandemrix to be used only in the absence of seasonal trivalent influenza vaccines, following link to very rare cases of narcolepsy in young people.

 

Finland also convened a Narcolepsy Task Force (see Finland: Task Force Report On Pandemrix-Narcolepsy Link) that confirmed an association – as yet unexplained  – between receipt of the vaccine and an increase in narcolepsy in children between the ages of 4 and 19.

 

Complicating matters, more than a dozen countries reported an increase in narcolepsy during the 2009 pandemic, even those where the adjuvanted vaccine was not used.

 

You can find details on one such study in Stanford Study Finds Influenza – Narcolepsy Connection  that linked narcolepsy not to the vaccine . . . but to infection by influenza virus itself.

 

Confused yet?

 

Alas, science isn’t always neat and tidy.  Good studies take time, and we don’t always get consistent results.

 

Today, we’ve another study that appears in the BMJ that is a bit more reassuring on the safety of the Pandemrix vaccine, but fails to answer the question of narcolepsy. 

 

It is called:

 

Neurological and autoimmune disorders after vaccination against pandemic influenza A (H1N1) with a monovalent adjuvanted vaccine: population based cohort study in Stockholm, Sweden

OPEN ACCESS

Carola Bardage, epidemiologist, Ingemar Persson, professor of pharmacoepidemiology and senior expert, Åke Örtqvist, county medical officer and associate professor, Ulf Bergman, professor of pharmaco-epidemiology and clinical pharmacologist, Jonas F Ludvigsson, paediatrician and epidemiologist, Fredrik Granath, senior biostatistician

 

This was a population based cohort study conducted in Stockholm, Sweden during the 2009 pandemic where 1,024,019  people were vaccinated with the Pandemrix vaccine and 921,005 remained unvaccinated.

 

Using the detailed healthcare registers for Stockholm County Council, researchers tracked all admissions to hospitals and visits to specialists for autoimmune or neurological diagnoses.

 

The conditions flagged in this study included:

 

• Guillain-Barré syndrome
• Bell’s palsy
• multiple sclerosis
• polyneuropathy
• anaesthesia or hypoaesthesia
• paraesthesia
• narcolepsy
• rheumatoid arthritis
• inflammatory bowel disease (ulcerative colitis, Crohn’s disease)
• type 1 diabetes

 

This study further divided this cohort into those who received the vaccine within the first 45 days of its availability, and those who received it later. Those in high risk groups, with comorbid conditions, were more likely to be vaccinated during the first 6 weeks of the vaccination campaign. 

 

The results (which are far more detailed in the open access report) indicated:

 

Conclusions

Results for the safety of Pandemrix over 8-10 months of follow-up were reassuring —notably, no change in the risk for Guillain-Barré syndrome, multiple sclerosis, type 1 diabetes, or rheumatoid arthritis.

 

Relative risks were significantly increased for Bell’s palsy, paraesthesia, and inflammatory bowel disease after vaccination, predominantly in the early phase of the vaccination campaign.

 

Small numbers of children and adolescents with narcolepsy precluded any meaningful conclusions.

 

The report summary states:

 

What is already known on this topic

• Studies are lacking on adverse events (except for narcolepsy) with any of the three vaccines used in the European Union against H1N1 during the pandemic period

• Available data are limited to case series or highly selected populations with short follow-up or no control group

What this study adds

• Excess risks for Bell’s palsy, paraesthesia, and inflammatory bowel disease after H1N1 vaccination with adjuvanted Pandemrix in Sweden were small but significant among more than one million vaccinated, but only in high risk groups targeted for early vaccination and who were likely to have earlier comorbidity

• The risk of Guillain-Barré syndrome, multiple sclerosis, type 1 diabetes, and rheumatoid arthritis remained unchanged

• Small numbers of children and adolescents with narcolepsy precluded any meaningful conclusions

 

While the low number of children and adolescents with narcolepsy may have precluded making any firm conclusions, their scarcity is nonetheless a bit reassuring.

 

The authors suggest that the small, but statistically significant increase in Bell’s palsy, paraesthesia, and inflammatory bowel disease among the early recipients of the vaccine may be partly, or perhaps entirely, explained by the higher number of high risk patients in that cohort.

 

We are still left with the mystery of what caused the increase in narcolepsy reported in Finland, of course. And there will no doubt be additional studies that will look at the safety of the Pandemrix vaccine in other regions.

 

But for now, as the authors state,  the news is `reassuring’.

 

For previous reports on the safety of (adjuvanted and unadjuvanted) flu vaccines, you may wish to revisit.

 

IOM Report On Vaccine Safety Concerns

 

BMJ: No Substantial Link Between Flu Vaccines And Guillain-Barre Syndrome

 

Lancet: Immunogenicity and safety Of Adjuvanted Flu Vaccines

 

NEJM: Study On China’s H1N1 Vaccine Safety

 

Harvard Study Reaffirms Safety Of Flu Vaccine

 

»» Read More

The Sonora/Arizona GBS Cluster

 

 

# 5694

 

 

Since the end of June the diligent newshounds on FluTrackers have been following reports of a growing number of `flaccid paralysis’ – sometimes described as Guillain-Barré Syndrome (GBS) – cases reported in Sonora Mexico and Southwestern Arizona.

 

The tracking thread, which as of today contains 35 – mostly Spanish-to-English translations - may be viewed here.

 

Those with good memories may recall that late last year another cluster of unexplained GBS-like cases occurred some 1500 miles to the south-east in Veracruz, Mexico.

 

I wrote about that outbreak twice (see Guillain-Barre Syndrome in Mexico, More On the Veracruz Paralysis Outbreak). Despite the detection of 38 cases, and several months of investigation, no definitive cause was determined.

 

Vaccines were eliminated from the suspect list, and the focus was on testing water, food, and environmental samples for toxins and bacterial contamination.

 

The Veracruz cluster dwindled in early 2011, and since then there have only been a few scattered cases of GBS in that region.

 

Since late last month Spanish Language newspapers in Sonora have been reporting on an unusual number of `flaccid paralysis’ cases and an elevated level of diarrheal diseases in their community.

 

Guillain-Barré Syndrome is an autoimmune disorder that causes muscle weakness ands sometimes paralysis. Most patients recover after a few weeks, although permanent nerve damage can remain.  On rare occasions, patients can die from the illness.

 

While all of the causes of GBS are not known, doctors do know that it often follows a bacterial or viral infection. 

 

This from the CDC’s Guillain-Barré syndrome (GBS)  Q&A page.

What causes GBS?

Many things can cause GBS; about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS.

People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

 

Late Wednesday afternoon the Yuma (Arizona) County Health Department issued a statement on the recent rise in diarrheal/Campylobacter cases and cluster of GBS-like cases in Southern Arizona and neighboring Sonora, Mexico.

Rare Condition Sparks Investigation

 

Posted Date: 7/13/2011 4:00 PM

Yuma County, Arizona, and San Luis, Sonora, have recently seen an increase in Campylobacter infection/acute diarrheal illness and Guillain-Barre’ Syndrome within their respective communities.

 

Campylobacter infection/acute diarrheal illness usually comes from a food or water source(s), and it causes diarrhea; sometimes with abdominal pain, and fever.

 

Campylobacter infection/acute diarrheal illness is one of the most common causes of diarrheal infection. Guillain-Barre’ Syndrome is a rare complication that can cause muscle weakness and sometimes paralysis. This condition is thought to be caused by an immune reaction response to a recent illness/infection.

 

The Yuma County Health District, along with the Arizona Department of Health Services, the Centers for Disease Control and Prevention (CDC) and Sonora health officials are working together to conduct an investigation into the source(s) of these health conditions.

 

“An investigation of this nature takes a lot of time and a lot of people. It’s like putting a puzzle together. You need all the pieces before you see the picture,” said Becky Brooks, Director of Yuma County Health District. “The response from all agencies has been great, and the expertise from each has certainly contributed to the investigation.”

 

Health officials from Arizona and Sonora have also conducted outreach and education and have asked physicians and hospitals to watch for the signs of GBS or Campylobacter infection and quickly contact their local health department with any possible cases.

 

It is important to note that GBS is not passed person to person and the best thing to do is to prevent gastrointestinal infections in the first place.

 

Good hand washing habits and safe food preparation go a long way to prevent common illnesses. Everyone should wash their hands thoroughly after using the bathroom, before and while they are cooking, and before eating.

 

Be sure to follow the four food safety tips: Clean, Separate, Cook, and Chill.

Clean: Wash hands, cutting boards, utensils, and countertops.
Separate: Keep raw meat, poultry, and seafood separate from ready-to-eat foods ( fruits, vegetables, food that do not require cooking).
Cook: Use a food thermometer to ensure that foods are cooked to a safe internal temperature: 145 F for whole meats (allowing the meat to rest for 3 minutes before carving or consuming), 160 F for ground meats, and 165 F for all poultry.
Chill: Keep your refrigerator below 40 F and refrigerate food that will spoil. Keep cold things cold and hot things hot.

• Seek medical care if you develop Gastrointestinal symptoms.
• Don’t prepare food for others if you have diarrhea or vomiting.
• Be especially careful preparing food for children, pregnant women, those in poor health and older adults.
• Washing your hands is the single most important thing you can do to prevent illness.

 

Since this release, the local media has picked up on the story.  A few examples include:

 

Mystery diarrhea outbreak in Yuma County, Mexico

Diarrhea Cases on the Rise, Yuma Health Officials Investigates

CDC investigating increase in illnesses in Yuma County

 

While fairly rare, GBS affects between 3,000 and 6,000 Americans every year.  Campylobacter infections, on the other hand, are very common, with an estimated 2.4 million cases in the U.S. every year.

 

This from the CDC’s  NCZVED information page on:

 

Campylobacter

What is campylobacteriosis?

Campylobacteriosis is an infectious disease caused by bacteria of the genus Campylobacter. Most people who become ill with campylobacteriosis get diarrhea, cramping, abdominal pain, and fever within two to five days after exposure to the organism. The diarrhea may be bloody and can be accompanied by nausea and vomiting. The illness typically lasts one week. Some infected persons do not have any symptoms. In persons with compromised immune systems, Campylobacter occasionally spreads to the bloodstream and causes a serious life-threatening infection.

 

(Continue . . .)

 

Although a campylobacter link has not yet been established, this GBS outbreak will  likely subside once the outbreak of diarrheal disease can be stemmed.

 

The newshounds on FluTrackers will continue to follow the story in the U.S. and Mexican press, and if anything unusual comes out of the CDC’s investigation, I’ll report on it here.

»» Read More

BMJ: No Substantial Link Between Flu Vaccines And Guillain-Barre Syndrome

 

 

Photo Credit PHIL

 

 

# 5688

 

The supposed link between flu vaccines and Guillain-Barre Syndrome (GBS) goes back to the 1976 swine flu scare and vaccination drive, where it was estimated that roughly 1 in 100,000 vaccine recipients developed the neurological disorder.

 

The vaccination program was halted after 40 million Americans received the vaccine, several hundred developed GBS, and the expected pandemic failed to show.

 

I was a young paramedic at the time, and chronicled my part in that bit of influenza history some time ago in Deja Flu, All Over Again. 

 

 

In the years since, while there has been little or no evidence of flu shots causing GBS, there remains a palpable level of public concern over vaccines – fears that anti-vaccine activists have played heavily upon in recent years.

 

The CDC, along with many other public health agencies, have allowed that the flu vaccine might carry with it a very low risk of developing GBS.

 

But most years the incidence is so low (perhaps 1 in 500,000 or 1 in a million) as to be nearly impossible to measure.

 

This from the CDC’s Guillain-Barré syndrome (GBS)  Q&A page.

 

What causes GBS?

Many things can cause GBS; about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS.

 

People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

 

 

Which brings us to a new study appearing yesterday in the BMJ (British Medical Journal) that looks at adjuvanted and unadjuvanted vaccine recipients across 5 European countries in 2009, and once again finds `no substantial link’ between taking the vaccine and GBS.

 

First some excerpts from the study, then I’ll return with more.

 

BMJ 2011; 343:d3908

• Research

Guillain-Barré syndrome and adjuvanted pandemic influenza A (H1N1) 2009 vaccine: multinational case-control study in Europe

OPEN ACCESS

Jeanne Dieleman,Silvana Romio, Kari Johansen, Daniel Weibel, Jan Bonhoeffer,Miriam Sturkenboom,

Abstract

Objective To assess the association between pandemic influenza A (H1N1) 2009 vaccine and Guillain-Barré syndrome.

 

Design Case-control study.

 

Setting Five European countries.

 

Participants 104 patients with Guillain-Barré syndrome and its variant Miller-Fisher syndrome matched to one or more controls. Case status was classified according to the Brighton Collaboration definition. Controls were matched to cases on age, sex, index date, and country.

 

Main outcome measures Relative risk estimate for Guillain-Barré syndrome after pandemic influenza vaccine.

 

<SNIP>

 

Conclusions The risk of occurrence of Guillain-Barré syndrome is not increased after pandemic influenza vaccine, although the upper limit does not exclude a potential increase in risk up to 2.7-fold or three excess cases per one million vaccinated people.

<SNIP> 

The authors conclude by stating:

 

Adjuvanted pandemic influenza A (H1N1) 2009 vaccines did not increase the risk of Guillain-Barré syndrome substantially, if at all.

 

While this study cannot state with absolute scientific certainty that the 2009 pandemic flu vaccine never caused a single case of GBS, they were unable to find any compelling statistical evidence that it did.

 

The qualifier of a `substantial link’  is used because, quite frankly, once you get down to an incidence rate as low as 2 or 3 cases out of a million, adverse effects can be almost impossible to detect.

 

Since viral infections can spark GBS, this study found that vaccination may actually have prevented some cases of Guillain Barre Syndrome – although those numbers are also too low to effectively measure.

 

Just under a year ago, in Lancet: The Influenza - Guillain Barré Syndrome Connection I wrote about a study where the authors stated that the risks of contracting GBS from the vaccine appear to be minor compared to the risks of developing GBS from catching the flu virus itself.

Like all studies, this BMJ study was subject to certain limitations, and additional studies are underway.  It is, however, the latest in a long list of reassuring research on the safety of flu vaccines. 

 

Of course, no vaccine (or drug) can be said to be 100% safe – and so rare but sometimes serious adverse effects have been reported.

 

As an example, there is an investigation in Europe into a possible link between the Pandemrix vaccine and a small number of cases of narcolepsy.

 

But then, even over-the-counter aspirin and NSAIDs contribute to thousands of hospitalizations and deaths each year.

 

It’s all about relative risks. 

 

And the risks from getting influenza – which kills tens of thousands every year - far exceed whatever slim risks that might be posed by getting the flu shot.

 

For more reassuring research on the safety profile of modern flu vaccines, you may wish to revisit the following blogs:

 

Harvard Study Reaffirms Safety Of Flu Vaccine

MJA: Safety Of Flu Shot In Young Children

NEJM: Study On China’s H1N1 Vaccine Safety

Lancet: Immunogenicity and safety Of Adjuvanted Flu Vaccines

 

The preponderance of evidence continues to support the scientific consensus that flu vaccines are very safe and most years, reasonably effective. 

»» Read More

More On the Veracruz Paralysis Outbreak

 

 

# 5157

 

 

Two days ago in Guillain-Barre Syndrome in Mexico, I wrote about a mysterious outbreak of acute flaccid paralysis in Mexico that at first was attributed to GBS, or Guillain-Barre Syndrome.

 

Since that time we’ve seen numerous news stories in the Mexican media, often with conflicting information.   FluTrackers has a thread with more than 50 posts on this outbreak, which has numerous translated news articles.

 

Early suggestions that this might in some way be connected to flu vaccinations (a common kneejerk reaction whenever GBS appears), are being dismissed by the Health Secretariat who announced that `of the 35 cases of acute flaccid paralysis, only two received the vaccine against seasonal influenza’.

 

Tonka, senior moderator on FluTrackers, posted a translation from an article from excelsior.com this morning.

 

SSA denies link with vaccine and H1N1 outbreak

The deputy director of epidemiology says there is no evidence that flaccid paralysis is caused by the vaccine and Guillain-Barré syndrome

Georgina Olson

• Strange outbreak sparks alert at Veracruz, and there are two dead

• Suman 33 patients with syndrome 'Guillain-Barre'

MEXICO CITY, Dec. 18 .- Of the 42 cases of acute flaccid paralysis have been presented in Veracruz and Nayarit none have been caused by the application of the vaccine against influenza A H1N1 or which is used to attack the influenza Seasonal also still have no evidence to prove that the disease is Guillain-Barré syndrome, said in an interview with Excelsior Dr. Hugo López-Gatell, deputy general director of epidemiology at the Health Secretariat (SSA).

"No, there is no evidence linking the vaccine against influenza A virus H1N1 or other influenza season, with the occurrence of these cases of acute flaccid paralysis," the official said.

(Continue . . . )

 

 

While all of this tells us what this outbreak isn’t, right now no one seems to know what this outbreak is.

 

According to media reports, of the (and the numbers here seem to vary a bit) 3 dozen or so cases reported so far, only 10 remain hospitalized.  

 

GBS-like symptoms (acute flaccid paralysis) can be caused by a variety of factors, including as sequelae from viral and bacterial infections, and even from environmental toxins.

 

According to another report on El Mundo, also posted by Tonka, health authorities are taking water, food,  and environmental samples from areas where these cases have been reported.

 

Performed first water sample

Staff of the Department of Health investigates the factors that can trigger paralysis, to make them known to the public and can be prevented.

Friday, December 17, 2010 Juliet H. Zambrano

 

 

All of these tests will likely take weeks.

 

The good news is that the number of cases does not seem to be expanding very rapidly, and that most of these cases are resolving fairly quickly.

 

For now, however, the cause of this outbreak remains unknown.

 

I’ll update this story from time to time, but you can follow this thread on Flutrackers to keep up with the latest news reports.

»» Read More

Guillain-Barre Syndrome in Mexico

 

 

 

 

# 5148

 

 

Every once in awhile we see reports of unusual disease activity from around the globe. Our first hint of something amiss often comes from (usually) fragmentary reporting in the local media, and is often first detected by the newshounds on the flu forums.

 

These early media reports are often incomplete, conflicting, and difficult to decipher. Many are machine translated into English, which can add another layer of ambiguity to the report.

 

So I tend to wait before posting them, since the details often change over time.

 

That said, we’ve some curious reports out of Mexico this week of an outbreak of what they are generally  describing as either Guillain Barre Syndrome or acute flaccid paralysis.

 

Tonka on FluTrackers began a thread on these reports on December 12th, which you can follow here, and which now has 30 posts.  The latest media reports indicate that there are now 33 cases, and 2 deaths associated with this outbreak.

 

Although (almost inevitably) some media sources are mentioning vaccine-related adverse affects as a possible cause, health officials are cautioning people not to leap to any conclusions.

 

Yesterday’s Healthmap blog carried a short report yesterday on the outbreak, and ProMed Mail has an RFI (request for information) out as well.

 

While a country the size of Mexico (111 million people) could reasonably expect to see a couple of thousand cases of Guillain-Barre syndrome a year, the number and geographic clustering of these reports does seem out of the ordinary.

 

The diagnosis of GBS is primarily one of clinical assessment and exclusion.  Diagnosis, particularly in its early stages, can be difficult.

 

This from the CDC’s Guillain-Barré syndrome (GBS)  Q&A page.

 

What causes GBS?

Many things can cause GBS; about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS.

 

People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

 

Since this seems to be an unusual outbreak of the syndrome, we’ll obviously be keeping a close eye on the investigation.

»» Read More

Good News Is No News

 

 

 

# 4987

 

 

The headline from yesterday’s Daily Mail proclaims:

Experts admit swine flu jab `may cause’ deadly nerve disease 

By Jo Macfarlane
Last updated at 11:24 PM on 16th October 2010

 

And the lede reads:

Health chiefs have for the first time acknowledged that the swine flu jab may be linked to an increased risk of developing a deadly nerve condition.

 

Breaking news?   Well, hardly.

In fact, I’m having a hard time finding anything `new’ in this story which states that experts from the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) are looking at whether there might be a possible connection between last year’s swine flu shot and Guillain-Barre Syndrome.

 

According to this story, a recent report from the MHRA stated:

 

‘Given the uncer­tainties in the available information and as with seasonal flu vaccines, a slightly elevated risk of GBS following H1N1 vaccines cannot be ruled out. Epidemiological studies are ongoing to further assess this possible association.’

 

Apparently, this one statement –`a slightly elevated risk of GBS cannot be ruled out’. – is the basis for all this journalistic consternation.

 

According to this Daily Mail report, out of 6 MILLION swine flu shots given last year in the UK, 15 suspected cases of GBS were reported after vaccination.

 

• Missing from this report is the fact that every year, about 1500 people in the UK are diagnosed with GBS – most of whom never received the flu vaccine.
• No mention is made of the burden of deaths and/or hospitalizations in the UK from last year’s influenza pandemic.
• Also missing is the evidence that getting the flu is a far greater risk factor for developing GBS than is getting the flu shot (more on that later).

 

 

But I suppose including these factoids would just clutter up what is otherwise a perfectly good story, wouldn’t it?

 

First, a little about GBS from the UK’s Guillain-Barre Syndrome Support Group. (Note: CIDP (chronic inflammatory demyelinating poly[radiculo]neuropathy) is considered a related disease).

 

Who can get GBS and CIDP?

Anyone: young or old, male or female. The illnesses are neither hereditary nor contagious. GBS affects about 1500 people every year in the United Kingdom; the incidence of CIDP is perhaps one tenth that of GBS.

What causes GBS/CIDP?

This is a matter of much research. About sixty percent of patients suffer from a throat or intestinal infection, influenza or stress symptoms in the previous two weeks. These infections trigger an incorrect response in the immune system which attacks the nerves.

 

While the exact cause of GBS isn’t well understood, scientists have known for decades that it often appears following a respiratory, or intestinal infection.

 

In 1976, an increased incidence of GBS in the United States was associated with that year’s Swine Flu shot, but repeated studies have failed to establish a link between subsequent flu vaccines and GBS over the past three decades.

 

For those interested in learning more about the events of that year, I would direct you to my blog essay Deja Flu, All Over Again.

 

 

The CDC, along with many other public health agencies, accept that the flu vaccine might carry with it a very low risk of developing GBS. But most years the incidence is so low (perhaps 1 in 500,000 or 1 in a million) as to be nearly impossible to measure.

 

This from the CDC’s Guillain-Barré syndrome (GBS)  Q&A page.

 

What causes GBS?

Many things can cause GBS; about two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with diarrhea or a respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS.

People also can develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks after getting a vaccination.

 

According to the CDC, here in the United States the background rate of GBS runs from between 80 to 160 new cases per week – regardless of vaccination status.

 

While there is always some small risk involved in taking a vaccine, in the face of our yearly flu epidemic (or last year, a pandemic) I’ve always maintained that it is a risk worth taking.

 

No medicine, no drug, and no vaccine is 100% safe for 100% of the people that take it.

 

Even aspirin and NSAIDs – sold over the counter – contribute to thousands of hospitalizations and deaths each year.   Penicillin, which has saved millions of lives over the years, can cause life threatening anaphylactic responses in some people.

 

All medicines are a double-edged sword.

 

That said, last year in excess of 12,000 Americans are believed to have died from the Swine flu, and the CDC estimates there were roughly 274,000 pandemic flu related hospitalizations.

 

A disproportionate number of those (90%) were under the age of 65.

 

Despite near-hysterical warnings over the safety of the pandemic vaccine, no deaths were attributed to the Swine flu shot (see CIDRAP VAERS study finds H1N1 vaccine safety similar to seasonal vaccines') and most reported side effects from the vaccine were minor, and temporary.

 

Only rarely did serious adverse reactions occur.

 

The truth is, the benefits of the flu shot far exceeded its risks.

 

As far as GBS is concerned . . . even if (and its a big `if’) vaccines were responsible for a handful of Guillain Barre cases last year . . . the flu almost certainly caused many more.

Two studies for you to ponder.

 

The first one comes from The American Journal of Epidemiology, and was published before the 2009 pandemic in September of 2008.

 

Investigation of the Temporal Association of Guillain-Barré Syndrome With Influenza Vaccine and Influenzalike Illness Using the United Kingdom General Practice Research Database

1. Julia Stowe, Nick Andrews, Lesley Wise and Elizabeth Miller

 

 

The entire study is available online, complete with graphs and charts, and supporting information.  But the `money quote’ from the abstract reads:

 

The authors found no evidence of an increased risk of Guillain-Barré syndrome after seasonal influenza vaccine.

 

The finding of a greatly increased risk after influenzalike illness is consistent with anecdotal reports of a preceding respiratory illness in Guillain-Barré syndrome and has important implications for the risk/benefit assessment that would be carried out should pandemic vaccines be deployed in the future.

 

 

And second, a more recent study that I covered earlier this summer (see Lancet: The Influenza - Guillain Barré Syndrome Connection) that also found that influenza – not the flu shot – was a significant trigger for developing GBS.

 

 

The Lancet Infectious Diseases, Volume 10, Issue 9, Pages 643 - 651, September 2010

doi:10.1016/S1473-3099(10)70140-7

Guillain-Barré syndrome after exposure to influenza virus

Original Text

Helmar C Lehmann MD, Prof Hans-Peter Hartung MD, Prof Bernd C Kieseier MD , Prof Richard AC Hughes MD

Summary

Guillain-Barré syndrome (GBS) is an acute, acquired, monophasic autoimmune disorder of peripheral nerves that develops in susceptible individuals after infection and, in rare cases, after immunisation. Exposure to influenza via infection or vaccination has been associated with GBS.

 

We review the relation between GBS and these routes of exposure. Epidemiological studies have shown that, except for the 1976 US national immunisation programme against swine-origin influenza A H1N1 subtype A/NJ/76, influenza vaccine has probably not caused GBS or, if it has, rates have been extremely low (less than one case per million vaccine recipients).

 

By contrast, influenza-like illnesses seem to be relevant triggering events for GBS. The concerns about the risk of inducing GBS in mass immunisation programmes against H1N1 2009 do not, therefore, seem justified by the available epidemiological data.

 

 

 

It’s within the realm of possibility that over time we’ll discover that modern flu vaccines may be responsible for causing a small number of GBS cases each year. The evidence for that is scant right now, but as the MHRA stated, it can’t be ruled out.

 

The evidence, on the other hand, showing that influenza (and influenza-like) viruses can be a trigger for GBS is far greater.

 

If you want to reduce your (admittedly small) risk of developing GBS this winter, the good news is that getting the flu shot is a pretty good strategy.

 

But of course, those who get their vaccine knowledge from the `popular press’, instead of The Lancet or The American Journal of Epidemiology , are unlikely to know that.

»» Read More

Lancet: The Influenza - Guillain Barré Syndrome Connection

 

 

# 4829

 

 

For more than 3 decades the public’s image of influenza vaccines has been tainted by memories of the 1976 swine flu shot which was associated with an unexpected increase in the number of GBS (Guillain Barré Syndrome) cases.

 

I’ve repeated the story, and my minor role in it, many times before.  But for those interested in the history of the 1976 Swine Flu program you may wish to read  Deja Flu, All Over Again. 

 

In the 34 intervening years, however, surveillance systems have failed to find any convincing evidence linking the neurological disorder with the influenza vaccine.  

 

It is believed that if such a link does exist, that it occurs so infrequently as to be practically undetectable.  The statistic of 1 case out of 1 million vaccinations is often mentioned, but no one really knows.  

 

But we do know that GBS  most often occurs after a viral or bacterial infection, and here in the United States, can be expected to strike several thousand people each year.

 

The CDC has a fact sheet on GBS, which states in part:

 

Fact Sheet: Guillain-Barré Syndrome (GBS)

December 15, 2009, 3:30 PM ET

Guillain-Barré syndrome is rare

Guillain-Barré syndrome (GBS) is a rare disorder in which a person’s own immune system damages the nerves, causing muscle weakness and sometimes paralysis. GBS can cause symptoms that last for as little as a few weeks, or go on for several months. Most people recover fully from GBS, but some people have nerve damage that does not go away. In rare cases, people have died of GBS, usually from not being able to breathe due to weakness of their breathing muscles.

GBS may have several causes

While it is not fully known what causes GBS, it is known that about two-thirds of people who get GBS do so several days or weeks after they have been sick with diarrhea or a lung or sinus illness. An infection with the bacteria Campylobacter jejuni, which can cause diarrhea, is one of the most common illnesses linked to GBS. Although rare, people can also get GBS after having the flu or other infections such as Epstein Barr virus. Except for the swine flu vaccine used in 1976, no other flu vaccines have been clearly linked to GBS.

 

Despite the warnings of the anti-vaccine crowd - many of whom predicted massive deaths and injury from the shot -  the evidence has shown that the pandemic shot given here in the United States and in Canada was extraordinarily safe.

 

A few blogs on the safety of the 2009 H1N1 vaccine include:

 

MMRW: Surveillance For GBS Among H1N1 Vaccine Recipients

What A Difference Three Decades Makes

VAERS Vaccine Safety Report

 

All of which brings us to a Lancet article (hat tip @jnwilliams76) that, alas, is behind a pay wall. A pity since I’d love to see their data.

 

What we do have access to is the abstract (below - slightly reformatted for readability) where the authors state that the risks of contracting GBS from the vaccine appear to be minor compared to the risks of developing GBS from catching the flu virus itself.

 

 

The Lancet Infectious Diseases, Volume 10, Issue 9, Pages 643 - 651, September 2010

doi:10.1016/S1473-3099(10)70140-7

Guillain-Barré syndrome after exposure to influenza virus

Original Text

Helmar C Lehmann MD, Prof Hans-Peter Hartung MD, Prof Bernd C Kieseier MD , Prof Richard AC Hughes MD

Summary

Guillain-Barré syndrome (GBS) is an acute, acquired, monophasic autoimmune disorder of peripheral nerves that develops in susceptible individuals after infection and, in rare cases, after immunisation. Exposure to influenza via infection or vaccination has been associated with GBS.

 

We review the relation between GBS and these routes of exposure. Epidemiological studies have shown that, except for the 1976 US national immunisation programme against swine-origin influenza A H1N1 subtype A/NJ/76, influenza vaccine has probably not caused GBS or, if it has, rates have been extremely low (less than one case per million vaccine recipients).

 

By contrast, influenza-like illnesses seem to be relevant triggering events for GBS. The concerns about the risk of inducing GBS in mass immunisation programmes against H1N1 2009 do not, therefore, seem justified by the available epidemiological data.

 

However, the experiences from the 1976 swine flu vaccination programme emphasise the importance for active and passive surveillance to monitor vaccine safety.

»» Read More

MMRW: Surveillance For GBS Among H1N1 Vaccine Recipients

 

 

# 4616

 

 

The MMWR (Morbidity and Mortality Weekly Report) from the CDC has preliminary results of surveillance for GBS (Guillain Barre Syndrome) – a rare neuromuscular disease – among those who did, and did not, receive the pandemic flu shot.

 

As you may recall, for reasons that have never been adequately explained, we saw a 10-fold higher rate of GBS among recipients of the 1976 swine flu vaccine than the background rate of the disease, which caused the cessation of the vaccination program and resulted in numerous claims of damage.

 

Since that time, there has a faint link between trivalent flu vaccines and GBS, with estimates that flu vaccines might be responsible for 1 extra case of GBS out of every million shot recipients.

 

When you are dealing with side effects that are that rare, the true incidence can be very difficult to nail down.

 

The numbers are still coming in, and being analyzed, but the good news here is that the incidence of GBS among pandemic vaccine recipients appears to be in line with that which has been seen from the seasonal flu vaccine in the past.

In other words, less than 1 extra case in a million.

 

Far more people who went unvaccinated developed GBS than did those who got the vaccine.

 

Among those who were vaccinated and developed the disease, 59% reported an antecedent illness – often a trigger for GBS – and so it is by no means certain that all of those cases can be linked to the vaccine.

 

The MMWR report is lengthy, but worth reading in its entirety.  I’ve just reproduced (and reformatted) the first paragraph.

 

 

Preliminary Results: Surveillance for Guillain-Barré Syndrome After Receipt of Influenza A (H1N1) 2009 Monovalent Vaccine --- United States, 2009--2010

Early Release

June 2, 2010 / 59(Early Release);1-5

Guillain-Barré syndrome (GBS) is an uncommon peripheral neuropathy causing paralysis and in severe cases respiratory failure and death. GBS often follows an antecedent gastrointestinal or upper respiratory illness but, in rare cases, can follow vaccination.

 

In 1976, vaccination against a novel swine-origin influenza A (H1N1) virus was associated with a statistically significant increased risk for GBS in the 42 days after vaccination (approximately 10 excess cases per 1 million vaccinations), a consideration in halting the vaccination program in the context of limited influenza virus transmission (1).

 

To monitor influenza A (H1N1) 2009 monovalent vaccine safety, several federal surveillance systems, including CDC's Emerging Infections Program (EIP), are being used. In October 2009, EIP began active surveillance to assess the risk for GBS after 2009 H1N1 vaccination.

 

Preliminary results from an analysis in EIP comparing GBS patients hospitalized through March 31, 2010, who did and did not receive 2009 H1N1 vaccination showed an estimated age-adjusted rate ratio of 1.77 (GBS incidence of 1.92 per 100,000 person-years among vaccinated persons and 1.21 per 100,000 person-years among unvaccinated persons). If end-of-surveillance analysis confirms this finding, this would correspond to 0.8 excess cases of GBS per 1 million vaccinations, similar to that found in seasonal influenza vaccines (2,3).

 

No other federal system to date has detected a statistically significant association between GBS and 2009 H1N1 vaccination. Surveillance and further analyses are ongoing. The 2009 H1N1 vaccine safety profile is similar to that for seasonal influenza vaccines, which have an excellent safety record.

Vaccination remains the most effective method to prevent serious illness and death from 2009 H1N1 influenza infection; illness from the 2009 H1N1 influenza virus has been associated with a hospitalization rate of 222 per 1 million and a death rate of 9.7 per 1 million population.

 

(Continue . . . )

»» Read More

NVAC To Investigate Incidence Of GBS

 

# 2524

 

 

 

From Rob Stein of the Washington Post today we get a story that indicates that researchers are delving deeper into a possible link between the H1N1 pandemic vaccine and a very slight increase in the incidence of GBS (Guillain Barre Syndrome).

 

The data is preliminary, incomplete, and may yet prove to be unsubstantiated.  But a panel at the HHS’s NVAC (National Vaccine Advisory Committee) has voted unanimously to follow up with further research.

 

First the story from the Washington Post, then a few brief comments.

 

Study hints at H1N1 vaccine complications

Officials: Flu perils still outweigh risk

Sunday,  April 25, 2010 2:56 AM

By Rob Stein

THE WASHINGTON POST

Federal health officials are investigating the first hints of possible significant complications from the H1N1 vaccine, but they've stressed that the concerns probably will turn out to be a false alarm.

 

Officials' latest analysis of data has detected what could be a somewhat elevated rate of Guillain-Barre syndrome, which can cause paralysis and death; Bell's palsy, a temporary facial paralysis; and thrombocytopenia, which is a low level of blood platelets.

 

The data are being collected through five of the networks the government is using to monitor people who were inoculated against H1N1, also known as swine flu.

(Continue . . .)

 

 

Because of the problems experienced 34 years ago with the 1976 swine flu vaccine, doctors, researchers, and a small army of statisticians have been on the lookout for any possible spike in vaccine-related side effects with the 2009 H1N1 vaccine.

 

As with any drug, vaccines have the potential to cause adverse side effects.  There is no such thing as a 100% safe drug.

 

A risk-reward calculation must be made to decide if the benefits of a drug trumps any potential down-side to taking it.  Even over-the-counter medications, like Aspirin and NSAIDS, are known to cause thousands of severe medical complications each year.

 

Here in the United States recipients of this year’s flu vaccine have been under close scrutiny by a number of monitoring programs, including the VAERS (Vaccine Adverse Event Reporting System), the military (with over 1 million personnel getting shots, and intense follow up), and the VSD project (Vaccine Safety Datalink).

Their goal is to look for, analyze, and identify any risks from either the pandemic or the seasonal flu shot.  

 

This is the most scrutiny any influenza vaccination campaign has ever received, and so it isn’t terribly surprising that they are seeing hints of what may be very rare adverse reactions.

 

We’ll have to wait to see what is learned here, but even if a link is determined, it is important to keep things in perspective. 

 

Somewhere between 12,000 and 18,000 Americans likely died from the H1N1 virus over the past year, and most of those were under the age of 65.

 

While the vaccine came too late to prevent many of those fatalities, the vaccination of 80 million Americans is probably at least partially responsible for our not seeing a serious third wave this spring.

 

The vaccine, we can assume, probably saved some number of lives.   How many?   

 

Well . . .  I wouldn’t even want to begin to quantify that.  But I suspect it is a significant number.

If the vaccine is eventually linked to some small increase in the rate of GBS, or any other serous side effect for that matter, that risk must be balanced against the benefits it produced.   

 

And based on what we know right now, those benefits appear substantial.

»» Read More

What A Difference Three Decades Makes

 

 

# 4497

 

 

Thirty-four years ago – as a young paramedic – I was involved in the distribution of the much maligned 1976 Swine Flu vaccine. 

 

For months during the summer of that year, I spoke at civic organizations, schools, and churches about the upcoming flu season and the need for vaccination, and that fall, I gave thousands of flu shots.

 

 

Me, giving my famous `painless flu shot’.  Ignore the look on the lady’s face.

 

I described the events of that campaign some time ago in a blog entitled Deja Flu, All Over Again.  As most of you probably remember, that vaccine was plagued by a low - but significant -incidence of serious side effects.

 

Of them, Guillain-Barre syndrome (GBS) was the most famous.  It is believed to have contributed to the paralysis (usually temporary) of nearly 500 people, and the deaths of 25 others.

 

The vaccination program was brought to a halt in December after 40 million shots had been given, scores of people claimed injury, and the swine flu pandemic had failed to appear as predicted.

 

Of course, had the swine flu pandemic of 1976 arrived with the vengeance originally feared, then these side effects would have been considered acceptable losses.

 

It didn’t, and instead, this incident left the vaccine industry in a shambles and a public mistrust of vaccines in general.

 

In the three decades since that time, there has been no similar connection between influenza vaccines and Guillain-Barre syndrome.  This paralytic syndrome most often occurs after a viral or bacterial infection, and here in the United States, can be expect to strike several thousand people each year.

 

Fast forward 33 years, and a new `swine flu threat’ emerges.  As in 1976, it is an H1N1 virus, and once again a pandemic vaccine is rapidly moved into production.

Understandably, there were concerns -  even among the scientists who were producing and promoting the vaccine- over the remote possibility that some serious side effects might occur.

 

But there were some differences this time. 

 

• First, unlike 1976, the novel H1N1 of 2009 was already widely circulating, and claiming lives, when the decision was made to produce the vaccine.  
• Second, vaccine technology has improved considerably over the past 30+ years.  

 

 

While there is always some small risk involved in taking a vaccine, in the face of our yearly flu epidemic (or in this case a pandemic) I’ve always maintained that it is a risk worth taking.

 

No medicine, no drug, and no vaccine is 100% safe for 100% of the people that take it.  

 

Even aspirin and NSAIDs – sold over the counter – contribute to thousands of hospitalizations and deaths each year.   Penicillin, which has saved millions of lives over the years, can cause life threatening anaphylactic responses in some people.

All medicines are a double-edged sword.  

 

The CDC and the HHS, along with many other public health entities around the world have been watching to see if the pandemic vaccine released could be linked to adverse effects, and Guillain-Barre syndrome.    Much of this information comes from VAERS (Vaccine Adverse Event Reporting System).

Despite the hysterical warnings of the anti-vaccine crowd - many of whom predicted massive deaths and injury from the shot -  the evidence to date is that the pandemic shot given here in the United States and in Canada has been extraordinarily safe.

 

Some blogs on the relative safety of this year’s pandemic vaccine.

 

CIDRAP Reports On H1N1 Vaccine Safety

Canada Probes Adverse Vaccine Reactions

MMWR Vaccine Safety Report

VAERS Vaccine Safety Report

The Background Is Always In Motion

 

Which brings us to today’s research, presented at the American Academy of Neurology's 62nd annual meeting in Toronto, that showed a very low incidence of GBS (Guillain-Barre Syndrome) among those who received the H1N1 shot.

 

A brief excerpt from an article that appeared in The Globe & Mail.  Follow the link to read it in its entirety.

 

Incidence of Guillain-Barré Syndrome was low with H1N1 vaccine, researchers report

Carly Weeks

Globe and Mail Update Published on Tuesday, Apr. 13, 2010 7:33PM EDT

(EXCERPT)

U.S. researchers presented a study yesterday at the American Academy of Neurology’s annual meeting, taking place in Toronto this week, that showed reports of Guillain-Barré Syndrome associated with H1N1 vaccination in the U.S. were extremely low.

 

Specifically, there were 6.2 reports of the syndrome for every 10 million H1N1 vaccinations administered last year. Meanwhile, researchers said there were 10.6 reports of GBS for every 10 million seasonal flu vaccinations given last year. The rates are low, and similar to those observed during other vaccination campaigns.

A similar incidence of GBS was reported in Canada among (adjuvanted) shot recipients, of about 1 case per 1 million people.

 

A rate less than, or equal to what might be expected in the general (unvaccinated) population.

 

Whether adjuvanted (as in Canada and Europe) or unadjuvanted (as in the US and some other countries) vaccines, the evidence continues to show that the pandemic and seasonal flu shots are exceptionally safe.

»» Read More