Friday, June 13, 2008

Dr. Omer on Vaccines

I don't spend too much time writing on this blog about vaccines. The reason is not that I don't think it is important - I think this is a very important issue that spans health, politics, science, human and financial resources, and quality of life issues for autistics. The main reason I don't spend too much time on it is that other bloggers such as Kev et al., Prometheus, Kristina, Mike, and Kathleen among many others do such a thorough and marvelous job with current analysis. I appreciate their efforts, and I hope they all know that.

What prompted this post is an interview I read today on a website called Science Progress. The interview was with Dr. Saad Omer, whose credentials you can find here on Johns Hopkins Bloomberg School of Public Health's faculty page. It really caught my attention because I think Dr. Omer has a very clear, concise, well-organized approach to describing where current knowledge stands in relation to vaccine safety and autism causation issues. Here is a set of assertions that is sensitive to all "sides" of the debate, that does not pussy-foot around adverse vaccine reactions, and yet falls back on the current science to draw current conclusions.

As the parent of an autistic child, I am often asked my thoughts on vaccines. There are so many talking points and subtleties that I often find it difficult to summarize why I have arrived at my position without losing them in the details and finer points. So I am posting portions of the interview to my blog, linking to the rest of it, and can use this as a referral when asked this question in the future.

Here are some excerpts:

On the Hannah Poling case:
So to put things in perspective for that case—and in terms of people drawing conclusions from it—I would caution that this is just a case and the question I often ask, even within the scientific community is “where are the controls?” Because when we assess scientific evidence, we need to keep in mind that we need to compare an association of an event with an outcome in both cases and controls, we haven’t had that kind of evaluation yet.
On the Hannah Poling case's significance to autism causation:
And just to clarify why we are on this topic: even if this link is established, and what it says is that mitochondrial disorders, which are a kind of disorder in the cell’s energy mechanism, is proven to be exacerbated by vaccines and result in autism spectrum disorders, metabolic disorders are very rare and it would explain a very small proportion of autism diseases—just to put that in perspective.
On Evidentiary Standards for the VICP:
... the Special Masters of the compensation program, not the HHS, interpreted as having said that the evidence should be evaluated on a standard of “biologically plausible.” I think that’s dangerous, because I can sit here and come up with twenty or thirty different hypotheses which would be biologically plausible on several biological models. We are not talking about probable; we are talking about plausible ... So I think it’s not a very robust standard to go by because what we are saying is that we would have judgments on these cases based on something that could happen, not something that does happen.
On methods to maximize Vaccine safety:
One major program is the Vaccine Adverse Events Reporting system, which is jointly managed by the CDC and the FDA, and events that seem to be associated with vaccines are reported into that system. It’s a good system for generating signals but it has its limitations ... There was a recent analysis published in Pediatrics that showed that most of the rise in reports of autism-related symptoms associated with vaccines has been due to increased reporting of litigation-associated cases. So we have that kind of a problem with VAERS but it still has a lot of utility in terms of generating signals. For example, it generated a signal for the old rotavirus vaccine.
Then the CDC has the Vaccine Safety Datalink. They have put together a system by linking databases from several large HMOs, and it covers approximately two percent of the U.S. population of zero to six years.
Then there is the Clinical Immunization Safety Assessment Network, which is a network of a few centers of excellence, mostly academic centers, coordinated by the CDC, to assess vaccine safety in a clinical setting.
I must say, I think vaccine safety needs a lot more resources than it is provided. Because as I said, vaccine events are rare so you need large numbers to study these phenomena and the resources that are available are very low.
On the risks of not vaccinating:
On the other hand, we know that there is risk of—even an individual level risk—of acquiring vaccine-preventable diseases in the United States if your child is not vaccinated. For example, in a national-level study it was found that kids who are exempt from vaccination requirements had thirty-three times—not percent, it’s times—higher risk of acquiring measles with those who are vaccinated, who do not seek exemptions, and [in a Colorado study] six times higher risk of acquiring pertussis than those who are vaccinated. So there are real risks involved in terms of acquiring vaccine-preventable diseases
On Rubella - very interesting point:
One last point in this regard: we do know that congenital rubella syndrome is associated—and there are some studies showing an association—with autism-like symptoms. So we know that part of that syndrome is explained by a congenital rubella syndrome which used to occur when the population-level immunity in the U.S was relatively low. So actually, MMR vaccine prevents against something that is associated with autism. So if you are thinking specifically in terms of autism, one should consider that we are talking about something that prevents autism.
On sources of information:
It’s several sources. We found in our studies—looking at parents of children exempted from vaccination requirements, compared to those vaccinated—there was an association with types of provider, trust in government, the sources of information people tended to get, information from some of the advocacy sites tended to seek exemptions at a higher rate, etc. So yes. There are several sources of that, and there are passionate people who feel there is an association with vaccines and autism, and that includes some celebrities as well. So that gets people’s attention.
On concerned parents:
On the other hand I must say that most parents, even those that are concerned about vaccine safety, are coming from the right place. All of us want our children to be safe from any harm, including harm from any pharmaceutical interventions.
On adverse reactions and risk/benefit:
One thing that people should realize is that we know that vaccines have some side effects. And we should acknowledge that, everyone who is involved. However, the risk and benefit calculus for all vaccines that are out there, based on our current knowledge, heavily favors not only getting your child vaccinated, but also getting them vaccinated according to the specified schedule.
On spreading out the schedule:
I have seen a new trend where people are splitting the difference and saying, “OK, I’m going to get my kid vaccinated, but I’m going to get them vaccinated late.” Well the risk of illness is not constant across childhood and so that’s why the Advisory Committee on Immunization Practices and the American Academy of Pediatrics come up with these recommendations to look at several factors, including the burden of disease. So it’s important to not only get your child vaccinated, but also to get them vaccinated per specified schedule.
All bold emphasis is mine.


Kev said...

Good stuff Steve, thanks.

Club 166 said...

A lot of good, straight talk. Just the world needs more of.

Thanks, Steve.


Anonymous said...

Doing the math according to Dr. Omer and assuming 3% Unvaccinated for measles (9,120,000) and the number of current cases (64)

Rate (64/9,120,000) * 33 = .02%

Odds of being struck by lightning: 1/5000 = .02%

If you don’t worry about being struck by lightning, you shouldn’t be worried about getting measles either.

HCN said...

Mr. Anonymous:

The problem with your "math" is this: the unvaxed usually hang around in the same groups.

This is why in the recent surge of measles there were outbreaks in schools with lower than average vaccine uptake. In San Diego a kid returning from Switzerland with measles spread it in the charter school to a bunch of other unvaccinated kid (and in the doctor waiting room to at least three babies too young to be vaccinated... at least one ended up in the hospital), and in Grant County, WA all eight kids in one unvaccinated family got measles (three ended up in the hospital), and at last count eleven more got measles (total of 19, most from two private schools, and were unvaccinated).

Switzerland is facing a large increase in measles, and it spread to Salzburg, Austria in a Waldorf school of mostly unvaccinated kids.

Your math only works if the numbers were evenly spread out. They are not.

Anonymous said...

Is the number of individuals that are too young evenly spread? Is the number of individuals that are immune deficient and cannot be immunized evenly spread? Is the number of elderly too old to have ever received a vaccine evenly spread? Is the remaining pool of unimmunized a minority of these other populations? Are you determining distribution based on a city block, a state or the country? My numbers are fine. If anything they are conservative making lighting MORE dangerous.

Steve D said...

I agree with HCN's assessment of the math problem.

However, lets lay Mr. Anon's game for a moment.

U.S. Birth totals hover around 4.025M annually.
Vaccination rates exceed 90%
Vaccine schedule + recommended flu shots equals average of 12 vaccines per year.
# of vaccines administered per year to infants/children, then, is
4.025M * .90 * 12 = 43,470,000

Average # of petitions to VICP in FY 2005, 2006, 2007 is 489 (most of these are autism petitions, a total of 308 out of 489)

Rate of vaccine "table" injury is
489 / 43.47M = .000011

If you don't worry about measles or being struck by lightning, you shouldn't be worried about vaccines either.

Epi said...

Mr. Anonymous,
I'M not worried about getting measles and I'm not worried about YOU getting measles. I'm worried about YOUNG CHILDREN getting measles. The latest national percentage of 19 to 35 month old children unvaccinated for measles was 7.6% (+/-0.06%), with huge variation by state and locality (e.g. 15% in Nevada). And vaccinated children can get measles, so that doesn't mean that only 7.6% are susceptible. The rest of your "math" is ridiculously simplistic. A child's risk of measles is not a function merely of the number of recent cases in the U.S. The spread of measles in extremely complex, which is why some people, like Dr. Omer, make careers of infectious disease epidemiology. The principles of herd immunity, etc. can't be picked up from third grade multiplication tables. For an interesting start, try reading Thomas May and Ross Silverman, 'Clustering of exemptions' as a collective action threat to herd immunity. Vaccine 2003;21:1048-51.

Epi said...

steve d,

Good Point.

Steve D said...

I'll be the first to admit that I'm thrilled to have a real, live epidemiologist visit my tiny little corner of the internet.
Please, Epi, ignore my little bit of math in the prior post, as I was just playing along with Mr. Anonymous.
And thanks for visiting.

@Joe - Yes, that's what drew me to this article. I like Dr. Omer's non-condescending tone and his empathy to parents just wanting the best for their kids. That's a message that rings true with me.

@Kev - You're welcome.

Alyric said...

Ta Steve

You can never have too many sensible explanations of the complexities of vaccinations.

One question I have for thr vaccine experts - These adverse vaccine 'events' we're told about. Apart from allergies to egg albumin and such that just happen and possibly accidental septicaemia - poor quality control or poor storage, these tales of encephalopathy/epilepsy following vacines - is there a connection in reality? or is this simply folks assuming that there is a connection. I would like to know what the connection could be.

Anonymous said...

I will gladly update my calculations from estimates to actual when someone can provide the actuals.
Exactly how many people do not have immunity to measles for every reason?
Explain spontaneous outbreaks if there is no foreign exposure?
Explain why foreign exposure defeats herd immunity?
Explain how reducing risk of exposure, other than vaccination, is included in the calculation?
Justify your calculations to demonstrate all the necessary variables, both positive and negative, that arrive at the current number of case and reasoning for the locations noted on the CDC web site.

Epi said...


I’m not a vaccine expert. I’m a retired Ph.D. pediatric epidemiologist. Anyway, about encephalopathy: In the late 1990s, some American citizens expressed concern that bovine spongiform encephalopathy (BSE) might be transmitted through vaccines. The FDA’s Center for Biologics Evaluation and Research (CBER) conducted a careful review of the science related to the issue. CBER held a joint meeting of the two committees involved (the Transmissible Spongiform Encephalopathy Advisory Committee and the Vaccines and Related Biological Products Advisory Committee) on July 27, 2000. At that session, FDA statisticians presented their calculations that the theoretical risk of any bacterial or viral vaccine contamination by the agent of BSE was remote, ranging from 1 in 2 billion to 1 in 200 billion doses. Further reassurance came from CDC's surveillance of neurologic disorders, which revealed no cases of variant Creutzfeldt-Jakob disease (vCJD, the human form of BSE) in the USA. Moreover, a review by British scientists of the 52 vCJD cases reported in Britain (published in the October, 2000 issue of Vaccine) shows that vaccine use appears to have no role in the development of the disease.

I hope this answers your question, at least partially.

Epi said...
This comment has been removed by the author.
Epi said...

Mr. Anonymous,

Your question(s) can't be serious. If they are, see steve d's original response.

María Luján said...

Hi Alyric
Of course I am not a vaccine expert. But I have studied the topic, recopilating information and discussing it with several doctors.
If you are interested about what is published on the issue of encephalopathy and autism, I may post some links. Please let me know

Anonymous said...

I haven't been approaching Dr.Omer's statements from the right perspective. Let's reverse engineer what he has said:

“For example, in a national-level study it was found that kids who are exempt from vaccination requirements had thirty-three times—not percent, it’s times—higher risk of acquiring measles with those who are vaccinated”

When was the study done and what was the risk of acquiring measles if vaccinated at that time?

Has the risk of acquiring measles changed since that date? If so, why?

Science Progress also started the interview with ambiguity by asking about “exempt” from vaccination without defining if “exempt” is ONLY by choice or all individuals that are not vaccinated. Two very different numbers.

Anonymous said...


As long as we are "playing the game"

Current rate of measels for those under the age to get vaccinated=

14/4.025M = .0000035

Rate of Vaccine table injury=

So you are statistically 3 times more likly to be in the table injury then to get measels.

Epi said...

Mr. Anonymous,

The study cited by Dr. Omer was published by JAMA and the entire paper is available at Instead of asking us questions, your homework assignment is to carefully read the paper and come back to us with a report.

HCN said...

Another think that Mr/Ms Anon is forgetting is that no child under the age of one year has been vaccinated with the MMR. Each and every one of those children are susceptible to getting the real disease.

Which is what happened to three babies when a child with measles went to see the doctor. Just by walking through the waiting room three children too young to be vaccinated became very ill (one was hospitalized).

Also, there is a more recent paper on the same theme but with pertussis by Dr. Omer and others:

Anonymous said...

Thank you for providing the link, it was very informative and very useful.

It was very nice of Dr. Omer to cherry pick a 9 year old study that references data that is 16 to 23 years old and that includes a major outbreak of measles but ends just prior to the beginning of a very precipitous drop in the number of cases, both in the US and Globally, since that study.

1989 alone was ninety nine times, not percent, bigger than the current number of cases to date.

Dr. Omer’s statement “For example, in a national-level study it was found that kids who are exempt from vaccination requirements had thirty-three times—not percent, it’s times—higher risk of acquiring measles with those who are vaccinated, who do not seek exemptions” holds the same amount of weight as “You can get a 20% return if you invest in Enron, Worldcom, or AOL today!”

Some data points in the study include medical exemptions as part of the exemptors. The risk of contracting measles was never given in the study and can only be obtained by request of the authors. The study was done DSM III so autism wasn’t an issue for exemptors.

There were MANY assumptions that were normalized, or used statistical modeling rather than actual data. The “math” of the study may not add up according to some.

“We calculated the number of vaccinated individuals by assuming a 98% national vaccination coverage rate for school-aged children and adolescents, based on unpublished CDC school-survey data of yearly coverage by state and antigen. All states reported at least 98% vaccination coverage among school-aged youth for measles in the period 1985-1992.”
Is 98% valid in 2008?

“We assume that the vaccine reduces the transmission probability to each child by a given fraction, which is the vaccine efficacy.”
“Estimation of efficacy also may be biased if vaccination is not random or if a vaccinee and a nonvaccinee do not have the same exposure to the infecting agent.”
Definitely changes the risk of exemptors if they actively assure they are not exposed to the infecting agent.

“The distribution of the transmission probabilities over the communities was determined so that the overall numbers of expected cases in exemptors and nonexemptors were close to the observed frequencies.”
“We used age-specific population data from the Bureau of the Census to extrapolate the percentages into estimated numbers. Thus, we were able to estimate age-specific measles incidence and the relative risk of measles for exemptors compared with vaccinated persons. “
Would the individuals that do not respond to a census requests most likely be vaccinated? Does the Bureau of the Census accurately report that population over time?

Given more recent information, Dr. Omer’s estimate is vastly overstated. Most likely you are 33 times more likely to be struck by lightning then to catch measles.

See my previous post concerning those who are under the age to be vaccinated (and included in CDC information)

HCN said...

Anon said "HCN:
See my previous post concerning those who are under the age to be vaccinated (and included in CDC information)"


Anonymous said...

Current rate of measels for those under the age to get vaccinated=

14/4.025M = .0000035

Anonymous said...

Simple math problem 2:

The only way to prove the 33 times still holds true:

Prove that both the number of exemptor cases and the number of vaccinated cases can never converge to zero and run parallel.

Otherwise the relative risk is a function of those two lines.

64 in 304,000,000 =0.0000002

Laura said...

I think the backlash against modifying the schedule is reactionary and ill-conceived. Spreading the vaccines out doesn't necessitate a delay. I'm not going to pretend to be an expert on immunizations. But common sense is that you don't have to bundle four vaccines into one shot. Moreover, the chicken pox vaccine doesn't work well, and the risk associated with foregoing it isn't great - after all, we weren't vaccinated for chicken pox.

To be clear, I'm not positing a causal link between vaccines and autism. But I witnessed my son have multiple adverse reactions to his 18 month shots, and in this mother's opinion, it wasn't humane. And it was avoidable because they could have been spread out.

Epi said...

For information on the varicella (chickenpox) vaccine, see at the The National Network for Immunization Information. Readers can judge for themselves.

Epi said...

Readers may also be interested in the article, "Do Multiple Vaccines Overwhelm the Immune System?", also at the website of The National Network for Immunization Information, at

Chuck said...

How much did the hospitalizations and deaths as a result of shingles increase after 1995 as a result of the Chicken pox vaccine?

Anonymous said...

Hey Epi,

I did my homework assignment and you never told me how I did.

Anonymous said...

Addressing all those research papers supporting the doctrines of vaccination, these should be taken with 'a grain of salt'
An article in the most recent issue of Nature addresses the fact of significant fraud in research.

Many researchers would like to believe that scientific misconduct is very rare. But news reported in this issue (see page 969), and the survey results reported by Sandra Titus and her colleagues on page 980, challenge that comfortable assumption. Titus's team found that almost 9% of the respondents in their survey, mainly biomedical scientists, had witnessed some form of scientific misconduct in the past three years, and that 37% of those incidents went unreported."
For some people, to vaccinate or not is an issue of trust. When government/pharma sponsored research is so obviously self-serving and unreliable, it is no wonder people have been shunning vaccinations.
And from an older study:
iv. Study Coordinator Accused Of False Statements

The Food and Drug Administration (FDA) and the United States Attorney for Massachusetts charged Anne Butkovitz, a clinical study coordinator, with making false statements regarding follow-up safety calls to human subjects enrolled in a recent study. Press Release, U.S. Department of Justice, Clinical Study Coordinator for Pediatric Drug Charged with Fraud (May 25, 2005). According to the Information (the charging document), the researcher was responsible for contacting the parents of children taking an experimental vaccine to inquire about "serious adverse experiences" (SAEs). Information, United States v. Butkovitz, Case No. 05-CR-10128-DPW (D. Ma.) The government alleged that the coordinator never made these contacts but instead falsified records to indicate that contact had been made and that no SAEs had been reported. Id. The U.S. Attorney reported that if Ms. Butkovitz is convicted, she could be imprisoned for five years, serve three years of supervised release, and pay a $250,000 fine. Press Release, U.S. Department of Justice, May 25, 2005.

The scientific community claims a monopoly on the truth because they supposedly have the 'research' to support their claims.
This self-serving research helps only the vaccine makers and their paid liars.

Epi said...


How much did the hospitalizations and deaths as a result of shingles increase after 1995 as a result of the Chicken pox vaccine?

This is a good -- and important -- question. Unfortunately, herpes zoster (shingles) is not a nationally notifiable disease in the United States, so there's not a straightforward answer. I spent a few hours reviewing the literature in hopes of giving you something close to a definitive answer. My conclusion is that we just don't know the answer yet. Some studies showed a decrease in shingles morbidity and mortality, some showed an increase, and some found that rates remained stable over time. At the end of my literature search (I started in 1995 and moved forward in time) I came across a literature review from March 2008, which pretty much agreed with my conclusion. In a review in the Journal of Infectious Diseases, Dr. Meredith Reynolds and four other authors from CDC conclude: "Since [1995], studies monitoring herpes zoster (HZ) incidence have shown inconsistent findings...Studies from Canada and the United Kingdom have shown increasing rates of HZ incidence in the absence of a varicella vaccination program. Data suggest that heretofore unidentified risk factors for HZ also are changing over time. Further studies are needed to identify these factors, to isolate possible additional effects from a varicella vaccination program. Untangling the contribution of these different factors on HZ epidemiology will be challenging." (See

Chuck said...

If it was a good and important question, why wasn't it asked before the introduction of the chicken pox vaccine?

Epi said...


"If it was a good and important question, why wasn't it asked before the introduction of the chicken pox vaccine?"

As I said in one of my comments above, I'm not a vaccine expert. I never did research on vaccines or worked on vaccines. According to the 1996 public document the CDC put out justifying the go-ahead for the chickenpox vaccine program: "The incidence of herpes zoster after varicella vaccination among otherwise healthy children is approximately 18 per 100,000 person years of follow-up (Merck and Company, Inc., unpublished data). A [published] population-based study indicated that the incidence of herpes zoster after natural varicella infection among healthy children was 77 per 100,000 person years. However, these two rates should be compared cautiously, because the latter rate was based on a larger pediatric population that was monitored for a longer period of time than were the vaccinees. One case of herpes zoster has been reported among adult vaccinees, resulting in an incidence of 12.8 per 100,000 person years." That's it.

Knowing what we know now (or still don't know), a good argument could be made that in 1995 scientists did not know enough about shingles morbidity and mortaility subsequent to chickenpox vaccination to justify a nationwide chickenpox vaccine program. But don't blame me. I had nothing to do with this. If you feel strongly about this, write the CDC, write your congresspersons or Senators, or even write Dr. Omer or other scientists at the Institute for Vaccine Safety at Johns Hopkins.

Dawn said...

You are so wrong on everything. Vaccines cause more than just Autism. One rubella vaccine damaged my hearing last year. VAERS is a total joke as well as the Vaccine Injury Compensation Program. At the very same time, my baby suffered from high-pitched screaming, congestion, convulsions, developmental delays, and regression in milestones from some of his recommended vaccines. He actaully stopped performing tasks for over 1 yr. Developmental delays are usually a good indicator of future learning disabilities. Neither of us can seek compensation and none of our adverse reactions were reported by the three doctors involved. I've spoken with thousands of other victims or parents of them. I've showed the vaccine package inserts to neurologist, chemists, Audiologists, and Optometrists. I've viewed the U.S. Dept of Education's real statistics - as of 2007 1 in 67 elementary school children are in Special Ed for Autism! Many of the vaccine ingredients are found in chemistry labs with the skull and crossbones on the label. The standard dose for any vaccine is .5 ml. It doesn't matter what age, height or weight... .5 ml is what you get. Our government agencies will never admit to any wrongdoing because they didn't just do it to our country's children - but others as well. I've seen plenty of studies that prove vaccines cause all kinds of damage in predisposed individuals. The problem is that our U.S. papers don't report about them. Big Pharma is more powerful that one could ever imagine. Yes, it is about politics too. Clinton spoke of it during his presidency -New World Order. My 14 yr old son is in 8th grade. He has been to schools all over the country. You would not believe just how mentally deficient children are these days. Schools have lowered the bar and parents don't even realize it. I Will NEVER vaccinate again after viewing the CDC's reported statistics before/after each vaccine came on the market. They are a joke and a very profitable one might I add. After all, aren't 40% of our children on medication?? Please people - WAKE UP before it is too late. Purchase the Vaccine Safety Manual by Neil Z. Miller. Google Bernadine Healy, former director of NIH. Vaccines CAN AND DO cause Autism and so much more. No, it is NOT RARE EITHER!

Epi Wonk said...

Welcome, dawncrim, fulltime anti-vaccination troll. Okay, you've convinced me that I'm "so wrong about everything." The "self-serving research" of every vaccine scientist in the world "helps only the vaccine makers and their paid liars." The old pharma shill gambit, along with the world-wide conspiracy theory.