Category Archives: Vaccines

Nervous About Vaccine Safety? I Hope This IOM Report Reassures You

A hot news story this fall was from California, where students were forced to get the pertussis booster vaccine or they won’t be allowed in school. This new law was pushed because of a pertussis epidemic which has already killed 11 children, especially in areas like Marin county where vaccination rates had slumped. I’m a big fan of vaccines, and it’s clear to me and my colleagues that vaccines have been, and continue to be, one of the fundamental medical advances of the last few hundred years. But we are increasingly fighting a media war against the anti-vaccine crowd, and vaccination rates are dropping in some areas, often with predictably disastrous results as we now see in California.

We doctors now always need be on alert to counter the many anti-vaccine arguments, and now we have a major reinforcement in a new evidence-based  review of the 8 most common vaccines. This very important report is from the US Institute of Medicine, which is considered the gold-standard of objective, evidence-based reviews upon which many countries base their medical care. Or to put it another way — many lawsuits regarding vaccines would use IOM reports as their top evidence. (Here is the link to the IOM report, called “Adverse Effects of Vaccines: Evidence and Causality”.)

The most important take-home message from this study was that “the M.M.R. vaccine doesn’t cause autism, and the evidence is overwhelming that it doesn’t,” according to Dr. Ellen Wright Clayton, the chairwoman of the IOM panel. To put it more dryly, the IOM states, “evidence favors rejection of five vaccine-adverse event relationships, including MMR vaccine and autism and inactivated influenza vaccine and asthma episodes.” This certainly isn’t the first time scientists have found no link, but hopefully this IOM report can be the final nail in the coffin of the MMR-autism allegations.

So that’s the good news; the less good news is that there are some adverse reactions, sometimes severe, which vaccines can cause. The most concise review of the report’s pros and cons is from a Medscape report:

The IOM group decided that the evidence “convincingly” supports a link between

  • anaphylaxis and MMR, varicella, influenza, hepatitis B, meningococcal, and tetanus toxoid vaccines;
  • febrile seizures and MMR vaccine (such seizures almost always have no long-term consequences);
  • syncope and the injection of any vaccine;
  • deltoid bursitis and the injection of any vaccine;
  • disseminated Oka-strain varicella zoster virus, along with Oka-strain varicella zoster virus viral reactivation (both with and without other organ involvement) and varicella vaccine; and
  • measles inclusion body encephalitis and MMR vaccine in individuals with severe immune system deficiencies.

According to another set of committee conclusions with a lower certainty level, scientific evidence favorsaccepting a causal relationship between

  • anaphylaxis and HPV vaccine,
  • transient arthralgia in adult women and MMR vaccine,
  • transient arthralgia in children and MMR vaccine, and
  • a mild and temporary oculorespiratory syndrome and certain trivalent influenza vaccines in Canada.

Conversely, the committee stated that the evidence favors rejecting a causal relationship between

  • type 1 diabetes and MMR vaccine;
  • type 1 diabetes and diphtheria, tetanus, and pertussis vaccine;
  • Bell’s palsy and inactivated influenza vaccine;
  • asthma exacerbation or reactive airway disease episodes and inactivated influenza vaccine; and
  • autism and MMR vaccine.

In its deliberation on MMR vaccine and autism, the committee stated that it reviewed 22 studies for epidemiologic evidence but relied only on 5 that, unlike the others, were “reasonably valid” overall. Each of the 5 studies asserted that there is no causal relationship between the vaccine and autism.

The committee also reviewed 4 articles and weighed evidence for the biological mechanisms by which MMR vaccine could possibly trigger autism. Its report noted that one of those articles, authored by the controversial Andrew Wakefield, was retracted last year by its publisher, The Lancet. Earlier this year, a series of articles and editorials in the British Medical Journal called Wakefield’s article an “elaborate fraud.”

“The committee assesses the mechanistic evidence regarding an association between MMR vaccine and autism as lacking,” the report stated.

There was also a good review of this important research by the The New York Times, which mentioned how the chicken pox (varicella) vaccine can sometimes cause problems as adults:

The panel did conclude, however, that there are risks to getting the chickenpox vaccine that can arise years after vaccination. People who have had the vaccine can develop pneumoniameningitis or hepatitis years later if the virus used in the vaccine reawakens because an unrelated health problem, like cancer, has compromised their immune systems.

The same problems are far more likely in patients who are infected naturally at some point in their lives with chickenpox, since varicella zoster, the virus that causes chickenpox, can live dormant in nerve cells for decades. Shingles, a painful eruption of skin blisters that usually affects the aged, is generally caused by this Lazarus-like ability of varicella zoster.

 

The Flu Vaccine: Do You Need It This Year?

It’s that time of year again: flu shot season! Yes, your offices and schools are filled with plans for “flu shot days”. I’m sure you’re debating right now whether or not you or your kids need it. So, here’s my tip on the flu vaccine: It’s basically the same advice I gave last year, which is also consistent with the U.S. CDC: I think all healthy persons should consider the vaccine, especially if you are pregnant or in contact with infants. But — as I mentioned last year — please do not assume that the vaccine protects you 100% and that you can simply touch door handles and smile when someone sneezes in your face, falsely reassured that you’re protected.

I said this last year because of a large meta-analysis from the esteemed Cochrane group, which found only about a 73% reduced risk of the flu — in the most ideal situation. Plus, it barely seemed effective for kids under 2 years of age. Now, just this week, an even more specific meta-analysis just published in the Lancet Infectious Diseases shows an even less effective prevention: 59%. During the recent H1N1 years, it was a bit better at 69%. Here’s a bit from their abstract:

Interpretation:Influenza vaccines can provide moderate protection against virologically confirmed influenza, but such protection is greatly reduced or absent in some seasons. Evidence for protection in adults aged 65 years or older is lacking. LAIVs consistently show highest efficacy in young children (aged 6 months to 7 years). New vaccines with improved clinical efficacy and effectiveness are needed to further reduce influenza-related morbidity and mortality

So there you have it. So the question is; do you like those odds? No, it’s not 100% but it’s still darn good, in my opinion. We all hope a better vaccine is just around the corner with new technology, but let’s just get to the point:

  • I definitely plan to get the vaccine, as I am surrounded by sick adults and kids and I don’t want to give the flu to them.
  • In the same vein, any person in close contact to our most vulnerable patients (kids under 2; the very old; and people with chronic diseases) should really consider getting the vaccine, again to prevent you from giving it to your vulnerable loved one.
  • Pregnant women should definitely get the vaccine
  • Anyone who wants it can get it.

"An Elaborate Fraud" — MMR Vaccine/Autism Connection Finally Debunked

Readers may remember a couple posts I wrote last year discussing the British Medical Journal’s retraction of the famous 1990’s study that linked the MMR vaccine to autism. Last May, the same British doctor lost his license, and this month the same journal is publishing a series of investigative articles which highlight how that study wasn’t simply incompetent but actually was an “elaborate fraud”, with data altered to fit the erroneous findings. It was also discovered that the author, Dr Wakefield, was secretly paid by a legal team that was preparing lawsuits against vaccine companies. Here’s a description of the paper’s major fraud from an NPR article:

Where did the paper go wrong? (Reporter Brian) Deer counts the ways after scouring health records and interviewing the patients families and various doctors. A few of the lowlights:

  • Only 1 of 9 kids said to have regressive autism clearly had it. Three had no form of autism.
  • Contrary to the paper’s assertion that all the kids were normal before vaccination, five had some sort of preexisting developmental problems.
  • Behavioral problems the paper said popped up days after vaccination didn’t actually appear for months in some kids, a fact that undercuts the causality of vaccination.

I mention all this because, as a community health & family doctor, I believe that vaccines are essential to a child’s health, and I think this one fraudulent study by one bad doctor has caused incalculable damage to the vaccine system worldwide. Dr Wakefield has single-handedly scared off hundreds of  thousands of well-meaning parents from getting their children vaccinated, and since its original publication in the late 1990’s the rates of measles and mumps infections have rebounded. Many children have become ill — and yes, even died — from these easily preventable illnesses.

I personally feel that parents should be furious at Dr Wakefield for misleading them. I especially feel that parents of autistic children should be even more angry at him for falsely distracting them from legitimate research on potential causes of autism. The journal editors put it nicely:

“Perhaps as important as the scare’s effect on infectious disease is the energy, emotion, and money that have been diverted away from efforts to understand the real cause of autism and how to help children and families who live with it.”

Here’s another nice quote from a parent with an autistic son,  from a CNN article:

Stuart Duncan, a father who blogs about his son’s autism, said he understands why many cling to the discredited hypothesis, although no other research has reproduced Wakefield’s results.

“I feel bad for the parents who for a while have a normal child, who hugs and speaks and then shortly after they turn 2, they lose all words and no longer look them in the eye. I would look for someone to blame too. If they had just gotten vaccines, I would be pretty angry too.

“No news story is going to convince them of anything. When you have that much anger and frustration, it’s passion. They’re fighting for their children.”

For more official views, here’s a blurb from the journal editors:

The Office of Research Integrity in the United States defines fraud as fabrication, falsification, or plagiarism. Mr Deer unearthed clear evidence of falsification. He found that not one of the 12 cases reported in the 1998 Lancet paper was free of misrepresentation or undisclosed alteration, and that in no single case could the medical records be fully reconciled with the descriptions, diagnoses, or histories published in the journal.

Who perpetrated this fraud? There is no doubt that it was Wakefield. Is it possible that he was wrong, but not dishonest: that he was so incompetent that he was unable to fairly describe the project, or to report even one of the 12 children’s cases accurately? No. A great deal of thought and effort must have gone into drafting the paper to achieve the results he wanted: the discrepancies all led in one direction; misreporting was gross. Moreover, although the scale of the GMC’s 217 day hearing precluded additional charges focused directly on the fraud, the panel found him guilty of dishonesty concerning the study’s admissions criteria, its funding by the Legal Aid Board, and his statements about it afterwards.

Do You Need The Flu Vaccine? Maybe Not…

It’s definitely the middle of flu season already, and so far it isn’t so bad where I practice. I’m still having daily conversations with my patients about the flu vaccine — but who really needs the annual flu shot? There’s actually a very comprehensive new study which should help shed some light on this issue.

First, let’s just review the flu vaccine; available each fall, it’s a worldwide standardized collection of 3 influenza viruses that are presumed to be the upcoming season’s likely virus. The current 2010 vaccine also includes the H1N1 strain as one of the three strains. As I mentioned a couple months ago, the H1N1 pandemic was officially declared over but it is still around. More importantly, it never became the deadly pandemic we had feared it might. However, parents should know that H1N1 was more selectively deadly to toddlers and pregnant women, with the death rate for children over four times higher than is usual for the flu season, as you see in this graph from the American Academy of Pediatrics 2010 Policy Statement on Influenza:

Flu Deaths in Children 2006-2010
Flu Deaths in Children 2006-2010

“Universal Flu Recommendation”

As for who should get this year’s flu shot, the official recommendation from the US Centers for Disease Control is actually expanded from last year; they recommend that anyone over 6 months of age, whether healthy or sick, should consider getting the vaccine (as long as they don’t have the usual contraindications). Previously, many people in the 19-49 year old range weren’t considered, but this new recommendation includes everyone. This position by the CDC was endorsed by my American Academy of Family Practice as well as the American Academy of Pediatrics:

The AAP recommends annual trivalent seasonal influenza immunization for all children and adolescents 6 months of age and older. Special efforts should be made to immunize all family members, household contacts, and out-of-home care providers of children who are younger than 5 years; children with high-risk conditions (e.g., asthma, diabetes, or neurologic disorders); health care personnel; and pregnant women. These groups are most vulnerable to influenza-related complications.

How Effective Is The Vaccine?

There’s a brand-new meta-analysis from what I think is the world’s most esteemed and unbiased medical review team, the Cochrane Library. In their analysis of the best studies about the flu vaccine for healthy adults, they found a less-than overwhelming effectiveness for the flu vaccine in real-world situations in adults like missed work days:

Over 200 viruses cause influenza and influenza-like illness which produce the same symptoms (fever, headache, aches and pains, cough and runny noses). Without laboratory tests, doctors cannot tell the two illnesses apart. Both last for days and rarely lead to death or serious illness. At best, vaccines might be effective against only influenza A and B, which represent about 10% of all circulating viruses. Each year, the World Health Organization recommends which viral strains should be included in vaccinations for the forthcoming season.

Authors of this review assessed all trials that compared vaccinated people with unvaccinated people. The combined results of these trials showed that under ideal conditions (vaccine completely matching circulating viral configuration) 33 healthy adults need to be vaccinated to avoid one set of influenza symptoms. In average conditions (partially matching vaccine) 100 people need to be vaccinated to avoid one set of influenza symptoms. Vaccine use did not affect the number of people hospitalised or working days lost but caused one case of Guillian-Barré syndrome (a major neurological condition leading to paralysis) for every one million vaccinations. Fifteen of the 36 trials were funded by vaccine companies and four had no funding declaration. Our results may be an optimistic estimate because company-sponsored influenza vaccines trials tend to produce results favorable to their products and some of the evidence comes from trials carried out in ideal viral circulation and matching conditions and because the harms evidence base is limited.

It is indeed disturbing that the Cochrane group found that “there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies“, that “reliable evidence on influenza vaccines is thin“, and that “our results may be an optimistic estimate.”

Please note that this study only covered healthy adults and not children. The Cochrane group in 2007 reviewed the flu vaccines for children and found fair effectiveness in children over, but not under, 2 years:

The review authors found that in children aged from two years, nasal spray vaccines made from weakened influenza viruses were better at preventing illness caused by the influenza virus (82% of illnesses were prevented) than injected vaccines made from the killed virus (59%). Neither type was particularly good at preventing ‘flu-like illness’ caused by other types of viruses (33% and 36% respectively). In children under the age of two, the efficacy of inactivated vaccine was similar to placebo. It was not possible to analyse the safety of vaccines from the studies due to the lack of standardisation in the information given but very little information was found on the safety of inactivated vaccines, the most commonly used vaccine, in young children.

My Bottom Line

I do find the latest Cochrane meta-analyses very disturbing, and I am not as gung-ho as I was in previous years. However, I still recommend the flu vaccine for all my patients, and certainly for myself, my co-workers and my family. Perhaps it’s not as effective as we thought, but it still offers at least partial protection, and I am comfortable with the risk/benefit balance. But families and readers need to make up their own minds.

I still mostly recommend the vaccine especially for anyone in contact with infants, especially under 6 months, as well as frail elderly people. Those groups, especially the infants, are most vulnerable to any complications of the flu, and many die each year from complications. And since infants under 6 months aren’t eligible for the vaccine, their best protection is prevention of exposure — to have their loved ones and caretakers be as immune to the flu as possible. So while the vaccine may offer only partial protection, it’s still the best we have.
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How Effective is the Flu Vaccine? Surprising New Data…

It’s that time of year again: flu shots are here. We all are a bit shell-shocked after last year’s H1N1 pandemic madness, and many communites were divided on the pros and cons of the flu vaccine. So who really needs the annual flu shot? There’s actually a very comprehensive new study which should help shed some light on this issue.

First, let’s just review the flu vaccine; available each fall, it’s a worldwide standardized collection of 3 influenza viruses that are presumed to be the upcoming season’s likely virus. This 2010 vaccine, just now available, also includes the H1N1 strain as one of the three strains. As I mentioned a couple weeks ago, the H1N1 pandemic was officially declared over but it is still around and may still flare up. More importantly, it never became the deadly pandemic we had feared it might. However, parents should know that H1N1 was more selectively deadly to toddlers and pregnant women, with the death rate for children over four times higher than is usual for the flu season, as you see in this graph from the American Academy of Pediatrics 2010 Policy Statement on Influenza:

Flu Deaths in Children 2006-2010
Flu Deaths in Children 2006-2010

“Universal Flu Recommendation”

As for who should get this year’s flu shot, the official recommendation from the US Centers for Disease Control is actually expanded from last year; they recommend that anyone over 6 months of age, whether healthy or sick, should consider getting the vaccine (as long as they don’t have the usual contraindications). Previously, many people in the 19-49 year old range weren’t considered, but this new recommendation includes everyone. This position by the CDC was endorsed by my American Academy of Family Practice as well as the American Academy of Pediatrics:

The AAP recommends annual trivalent seasonal influenza immunization for all children and adolescents 6 months of age and older. Special efforts should be made to immunize all family members, household contacts, and out-of-home care providers of children who are younger than 5 years; children with high-risk conditions (e.g., asthma, diabetes, or neurologic disorders); health care personnel; and pregnant women. These groups are most vulnerable to influenza-related complications.

How Effective Is The Vaccine?

There’s a brand-new meta-analysis from what I think is the world’s most esteemed and unbiased medical review team, the Cochrane Library. In their analysis of the best studies about the flu vaccine for healthy adults, they found a less-than overwhelming effectiveness for the flu vaccine in real-world situations in adults like missed work days:

Over 200 viruses cause influenza and influenza-like illness which produce the same symptoms (fever, headache, aches and pains, cough and runny noses). Without laboratory tests, doctors cannot tell the two illnesses apart. Both last for days and rarely lead to death or serious illness. At best, vaccines might be effective against only influenza A and B, which represent about 10% of all circulating viruses. Each year, the World Health Organization recommends which viral strains should be included in vaccinations for the forthcoming season.

Authors of this review assessed all trials that compared vaccinated people with unvaccinated people. The combined results of these trials showed that under ideal conditions (vaccine completely matching circulating viral configuration) 33 healthy adults need to be vaccinated to avoid one set of influenza symptoms. In average conditions (partially matching vaccine) 100 people need to be vaccinated to avoid one set of influenza symptoms. Vaccine use did not affect the number of people hospitalised or working days lost but caused one case of Guillian-Barré syndrome (a major neurological condition leading to paralysis) for every one million vaccinations. Fifteen of the 36 trials were funded by vaccine companies and four had no funding declaration. Our results may be an optimistic estimate because company-sponsored influenza vaccines trials tend to produce results favorable to their products and some of the evidence comes from trials carried out in ideal viral circulation and matching conditions and because the harms evidence base is limited.

It is indeed disturbing that the Cochrane group found that “there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies“, that “reliable evidence on influenza vaccines is thin“, and that “our results may be an optimistic estimate.”

Please note that this study only covered healthy adults and not children. The Cochrane group in 2007 reviewed the flu vaccines for children and found fair effectiveness in children over, but not under, 2 years:

The review authors found that in children aged from two years, nasal spray vaccines made from weakened influenza viruses were better at preventing illness caused by the influenza virus (82% of illnesses were prevented) than injected vaccines made from the killed virus (59%). Neither type was particularly good at preventing ‘flu-like illness’ caused by other types of viruses (33% and 36% respectively). In children under the age of two, the efficacy of inactivated vaccine was similar to placebo. It was not possible to analyse the safety of vaccines from the studies due to the lack of standardisation in the information given but very little information was found on the safety of inactivated vaccines, the most commonly used vaccine, in young children.

My Bottom Line

I do find the latest Cochrane meta-analyses very disturbing, and I am not as gung-ho as I was in previous years. However, I still recommend the flu vaccine for all my patients, and certainly for myself, my co-workers and my family. Perhaps it’s not as effective as we thought, but it still offers at least partial protection, and I am comfortable with the risk/benefit balance. But families and readers need to make up their own minds.

I still mostly recommend the vaccine especially for anyone in contact with infants, especially under 6 months, as well as frail elderly people. Those groups, especially the infants, are most vulnerable to any complications of the flu, and many die each year from complications. And since infants under 6 months aren’t eligible for the vaccine, their best protection is prevention of exposure — to have their loved ones and caretakers be as immune to the flu as possible. So while the vaccine may offer only partial protection, it’s still the best we have.

Will You Get The Flu Vaccine? Click and Answer the Poll Below:

MMR Vaccine & Autism: Famous Study Now Retracted

Many parents have been concerned about the alleged links between the MMR vaccine and a possible link to autism. As I’ve mentioned before, all medical societies continue to state that there has never been convincing proof of this, and now there is even less. The esteemed medical journal Lancet, which started this whole issue in 1998 with a provocative study, now officially and fully retracts that earlier study. Discussed here on BBC News, this is a major retraction and hopefully will finally put to rest this issue. The retraction comes a week after Dr Andrew Wakefield, the lead researcher in the 1998 paper, was ruled last week to have broken research rules by the General Medical Council. There was apparently a major conflict of interest:

Dr Wakefield was in the pay of solicitors who were acting for parents who believed their children had been harmed by MMR.

But this move goes further by accepting the research was fundamentally flawed because of a lack of ethical approval and the way the children’s illnesses were presented.

The statement added: “We fully retract this paper from the published record.”

Last week, the GMC ruled that Dr Wakefield had shown a “callous disregard” for children and acted “dishonestly” while he carried out his research. It will decide later whether to strike him off the medical register.

I think this is a major news story, as Dr Wakefield and others have caused incalculable damage to all vaccine’s reputations, and many unvaccinated children are getting sick and dying of diseases that should have been eliminated long ago. I personally think it’s disgusting that Dr Wakefield didn’t tell anyone he was getting paid by people looking for a connection, so he had a huge bias to find such a result. He clearly should lose his license to practice.