What does "rare" mean?

[Mommy2Teagan]

So I keep seeing this pesky deceptive word "rare" when researching vaccine reactions. What in the world does "rare" mean? I mean, what percentage (of children with bad reactions) allows medical professinals to toss around the word "rare". Millions of children are being vaccinated. Even just one percent of millions is a lot to me. In MY mind that doesn't mean rare. Maybe "rare" is a relative term. I guess what I'm trying to ask is......is there some kind of calculation that is being used to determine what "rare" really is? I hope I'm not being too confusing in my question.

[Deborah]

it means they don't have accurate numbers, they don't want to have accurate numbers, but they do want to reassure parents and get them to vaccinate their children.

With the increased number of vaccines and the early age at which many vaccines are given, reactions aren't rare.

There is also the question of where you draw the line between a "normal" response to a vaccination and a "reaction."

Try reading through some product inserts for the vaccines which are on the schedule for your little one. They can be found online: http://www.vaccinesafety.edu/package_inserts.htm

[picked up the link from the links list at http://insidevaccines.com/wordpress ]

[alegna]

They don't know. Even VAERS admits that at best 10% of reactions are reported.

The CDC does admit that the chance of vax reaction is higher than the chance of catching any of the VADs.

-Angela

[shuttlt]

I know he's not exactly any body here's man of the week, but I'm reading Offit's Autism's False Prophets. My impression from that is that he considers events in the 1/15,000 and up range to be rare. In the section I'm on he's talking about rare in the context of the power of epidemiology to detect rare events, rather than quite in the sense you mean. The events in this range that he's discussing seem to be scary, but not permanently damaging.

[Harmony08]

Originally Posted by alegna

They don't know. Even VAERS admits that at best 10% of reactions are reported.

The CDC does admit that the chance of vax reaction is higher than the chance of catching any of the VADs.

-Angela

Where did you see this? I'm dying to know.

[shuttlt]

If you count any and all vax reactions, I'm sure they do concede this.

[alegna]

Originally Posted by Harmony08

Where did you see this? I'm dying to know.

It's in the pink book. If you do a search here the link has been posted.

-Angela

[shuttlt]

Oooooo I've not read this yet.

http://www.cdc.gov/vaccines/pubs/pin...safety-508.pdf

Today, vaccine-preventable diseases are at or near record lows. By virtue of their absence, these diseases are no longer reminders of the benefits of vaccination. At the same time, approximately 15,000 cases of adverse events following vaccination are reported in the United States each year (these include both true adverse reactions and events that occur coincidentally after vaccination). This number exceeds the current reported incidence of vaccine-preventable childhood diseases. As a result, parents and providers in the United States are more likely to know someone who has experienced an adverse event following immunization than they are to know someone who has experienced a reportable vaccine-preventable disease. Thus, the success of vaccination has led to increased public attention on health risks associated with vaccines.

[MyBoysBlue]

Originally Posted by Harmony08

Where did you see this? I'm dying to know.

Chapter 4: Vaccine Safety of the PinkBook third paragraph down.

http://www.cdc.gov/vaccines/pubs/pin...k-chapters.htm

[Deborah]

Okay, if moderately severe vaccine reactions occur at the rate of 1 in every 15,000 doses, then a child who gets all the doses will have a major chance of having a moderately severe reaction by the time they are 18 months old. Say 38 different vaccine doses (in various combos), just divide it into 15,000 and you have a chance of a vaccine reaction at one in 395, roughly. Which, from what I hear around, seems about right. That is a reaction that is uncomfortable enough to concern the parents for a few days and may have (or may not have) permanent consequences.

[ema-adama]

I used to think that 1 in X no. meant 1 in X no. of children, not doses
Of course it makes much more sense that it would be doses. Is there any way to know if by jamming as many doses into one needle as possible would make the risk higher or lower?

[Ruthla]

Also, how are they defining "reactions"? Are things like developmental regressions being lumped in with "sore spot on the vaccine site for 2 days"?

[shuttlt]

Originally Posted by Ruthla

Also, how are they defining "reactions"? Are things like developmental regressions being lumped in with "sore spot on the vaccine site for 2 days"?

In the context of the statement from the CDC about there being more adverse vax reactions than cases of the diseases we vaccinate against, I believe we are talking about VAERS. In that case we are talking about anything that somebody thought might have been a vaccine reaction and bothered to report. Two people could, I think, report the same case and count it twice. Other cases, it might be that nobody thought to report it. Other cases, nobody realized it was vaccine related.

I might be wrong, but I don't think VAERS is used to calculate the 1:15,000 odds ratios.

[Jugs]

In my experience, rare = "It didn't happen to my kid"

[shuttlt]

I thought the following quote might help:

Approximately 30,000 VAERS reports are filed annually, with 10–15% classified as serious (causing disability, hospitalization, life-threatening illness or death).

http://www.cdc.gov/vaccinesafety/vaers/

So, that's 3000-4500 serious reactions anually in VAERS.

Anybody know how many doses of vaccine are given anually.

[user_name]

Originally Posted by Jugs

In my experience, rare = "It didn't happen to my kid"

[alegna]

Originally Posted by shuttlt

I thought the following quote might help:


http://www.cdc.gov/vaccinesafety/vaers/

So, that's 3000-4500 serious reactions anually in VAERS.

Anybody know how many doses of vaccine are given anually.

And then multiply that out, because CDC and VAERS agree that at MOST 10% of reactions are reported.

-Angela

[Sileree]

Originally Posted by shuttlt

Anybody know how many doses of vaccine are given anually.

http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5201a1.htm

Maybe you could find the info here.

[ema-adama]

Makes me wonder why active surveilance is not in place. Especially when it has been recommended in the UK after finding more adverse events to the MMR than had been expected.

[shuttlt]

Originally Posted by ema-adama

Makes me wonder why active surveilance is not in place. Especially when it has been recommended in the UK after finding more adverse events to the MMR than had been expected.

I would have thought the logistics would be quite difficult. The NHS electronic records systems is late, way over budget and a bit broken. When that comes in it may well become much easier. One problem with such a system is that it has to be very accurate. If you are trying to detect something that only effects 1/100,000 vaccinations then it could easily be swamped by errors in inputting the data. As I recall the NIH had this problem trying to assess the dangers of mercury in vaccines 10 or so years ago.