Another Herd Immunity question

When a population has a level of lifelong immunity to a certain disease such that an epidemic of that disease cannot occur, the population is said to have herd immunity.

I am still very new at this, so I might be missing something glaringly obvious from people more experienced with epidemiology.

What stood out for me from the part that I inserted into my post is the life long immunity that is required for herd immunity to work. Each disease has a different herd immunity threshold. Measles is a disease that is often spokeמ about. So, the herd immunity threshold for measles is 83 – 94% immunity. I am interpreting this to mean that 83 – 94 percent of the population (from birth through to old age) is recquired to be immune – not just 83 – 94% of children are required to be vaccinated.

Why? In this article, I found it interesting that in the absense of circulating disease, immunity only last for 25 years. By having the disease circulating within the population, the population is exposed to regular ‘boosters’. Remove the disease, and the whole population is left at risk, unless they are kept up to date with vaccines.

What is potentially dangerous with this effect of waning immunity in adults is that adults can have much more serious complications from diseases like measles, mumps, and chickenpox. Essentially a large part of the population could potentially be at risk if they are relying on vaccine induced immunity for their immunity, and not up to date with boosters.

Another piece of the puzzle is that mothers pass on passive immunity to their infants through the placenta (I have read conflicting articles about whether breastmilk also confers passive immunity or not). And babies are protected from the disease of measles with this passive immunity. Again, from what I am understanding, passive immunity is not conferred when the mother relies on vaccine immunity, only if she herself contracted measles is the immunity passed to her infant. Which, theoretically could leave infants more at risk with most new mothers today not having had wild measles.

It is all theoretical. I have not heard of infants or adults coming down with measles.

I just am really struggling to get my head around these issues. I do not know if the scientists are factoring in waning immunity when they calculate the threshold herd immunity, but I am guessing they are not. I am guessing that it is assumed that the vaccine is fulfilling it’s potential to rid the human population of measles.

Measles

This was never a vaccine I thought about giving DS as in my mind he is safer having had the disease, like I did.

Recent discussion has highlighted to me just how much is not known about the vaccine, the disease and the risks with both. What is interesting ,is that it is fairly easy to find information on the risks for the disease and a bit harder, but still possible, to find the information on just *who* is at risk for developing complications from the disease. From the medical literature available, the vaccine would appear to be almost completely risk free for the vast majority of the population. There is no information available, so no discussion is happening. Only musings and frustration by those who want the information (parents, and seemingly often mothers)

So, what I have learnt.

Poverty seems to be the leading factor in developing complications. This does not mean that just because you have access to clean water and fresh food you are safe. You could still be malnourished. And you could still be treated with fever reducing drugs and antibiotics, which it would seem do not do the patient any favours. And there are children who have immune systems that are weak, making them more at risk. In my understanding the three things that put you at risk for complications are:

• the age at which you contract measles (under 2 and over 9 being the risky groups, with 5-9 years of age being the optimal age group)

• the individual state of health and access to a variety of fresh, mineral rich foods. (not malnourished – lacking in essential minerals, fats, proteins, vitamins)

• having a condition that results in a compromised immune system.

If you contract measles under the age of 2, breastfeeding decreases the risk of death. In Africa. So I do not know if this would be attributed to reducing the odds of being malnourished, or something else.

OK, so that is what I have learnt about the disease.

Now for the vaccine.

The measles vaccine has undergone some changes since it was first lisceneced for use in the USA in 1963. This was the  Edmonston B measles vaccine. This vaccine was very reactive, resulting in a high fever and a rash (sounds like measles). Vaccines that would use a virus that was even more attenuated (weakened) were developed around the world.

In 1965 a study was designed to test the further attentuated vaccine against the Edmonston B and a placebo (no mention of what this placebo was). The further attenuated virus still produced sufficient antibodies, but without such side effects (that had required immunoglobulin administration simultaneously with the vaccine). This vaccine was in use until 1975, in the US.

One of the further attenuated Edmonston vaccines, is the Shwartz strain, in use in the USA from 1965 – 1976. It is still widely used throughout the world.

Today the only measles vaccine liscened for use in the USA is the Moraten strain, lisenced in 1968.

I do not yet understand why other strains in use in other countries are not lisenced for use in the USA, but I am sure it would be interesting to find out.

Some other points for consideration when it comes to measles and the vaccine.

• The vaccine does not produce life long immunity in the absense of the wild virus circulating in the population. Requiring boosters for adults (a population that is more at risk for complications)
• Mothers who are relying on vaccine induced immunity do not have suffiient antibodies to pass through the placenta, leaving young infants more at risk, another population more at risk for serious complications.
• The risks for the vaccine are unknown.
• Recent reading in epidemiology brought to light an interesting idea. That the way a population receives immunity from a natural disease is essentially different from the way a population receives immunity from vaccination programmes – as in the pattern of exposure. And that populations that are exposed to a disease are better protected than a population exposed to a vaccine. Resulting in models that attempt to copy how a population would be exposed in nature and apply these principles in vaccination programmes.

To my thinking, the vaccination programme is a bit of groping in the dark and messing with peoples lives without knowing exactly what is happening. I for one would rather take my risk with the disease (as in have the disease) than with the vaccine. Too many unknowns for me.

Preventative Medicine

This has been on my mind somewhat and I am hoping to make a bit of sense now as I think things through.

I am very much at the beginning of my path into understanding how to create and protect the health of my family, with a lot of focus on DS. So far I have had a very strong sense that vaccinations are not the simple preventative medicine that they are presented as being. The more I look into it, the more I am learning that it is definitely not as simple as getting the vaccine and now I can rest assured my child will be free of disease and essentially healthy. There are a myriad of issues surrounding this complex issue.

While I have so far chosen not to vaccinate DS, I have not decided that I will never vaccinate him. I am looking into this carefully and have asked my DH to give me time as I try and unravel what role I want vaccination to play in our lives. It is such a personal decision.

Largely what got me thinking again about all of this was offering information to a friend who was trying to decide whether to offer her 1 month old the HepB vaccination after having declined at the birth. I ended up giving her information I had read about and she based her decision on my information. I do not feel comfortable with that. I fact checked myself and found my information to be true, but not up to date and the up to date information to have many problems with it’s validity. Anyway, the moral of the story is that each family has to choose for themselves. While I am sad that so many babies are being vaccinated without a second thought – it really is none of my business.

Back to vaccinations and the issues that I am trying to get my head around.

My attention was caught when I found out that there have never been any double blind placebo controlled studies done on the safety of vaccinations. No one actually knows what the long term affects are and from what I am understanding, trials are measuring one vaccine against the other – not against a placebo. Now, there are very good reasons for this. It is not ethical to give a child a placebo instead of a vaccine and possibly risk that child contracting a preventable disease for the sake a science. So, the scientists have their hands tied so to speak. Except that there is a growing population who choose not to vaccinate or to partially vaccinate or to delay vaccinating. But then it is not double blind….. It’s a bit of a mess. However, I am concerned enough to not rush into vaccinating my DS with a list of extra materials found in the vaccines such as aluminum, mercury, formaldehyde, bovine serum, gelatin, etc etc the list is quite scary. Of course the question arises as to what is a safe dose of these materials. Can it be determined what is a safe dose of aluminum for a newborn (who I understand metabolize aluminum differently from adults and older children – although I am still looking into this)? for a 2, 4 and 6 month old?

Anyway, the safety of vaccines is something that is by no means established – as far as I have found so far.

Another issue that I have been looking into is the efficacy of the vaccines. No vaccine has 100% efficacy. But some are more effective than others. And not all vaccines contribute to herd immunity for the disease they are vaccinating against.

Another issue is the diseases themselves. Are they the killer diseases that we are told they are? Perhaps the doctor who saw DS days after he was born and the other doctor who saw him 2 months after he was born really do beleive that my DS was sure to die without the vaccines. This is what they told me in very clear and scary terms. I have to assume this is what they beleive if this is what they told me so passionately. From the very little that I have managed to read, I am not convinced that the diseases that are vaccinated against are all the death sentence that they are made out to be. Nasty and sometimes very dangerous. But not a death threat or necessarily the threat of permanent disability that I was led to beleive. And something that I am only starting to look into… but what are the circumstances around children developing complications with childhood diseases? I cannot beleive that it is a matter of purely luck as to whether one child develops a serious complication and the other does not…. as yet I do not have any answers that fully satisfy my curiosity – for now I breastfeed DS, keep to an organic diet most of the time, use environmentally safe cleaning products, avoid white flour and processed sugar. These guidelines seem to cover my bases and the more I read, the more these guidelines are justified.

A case in point. Almost 6 months ago I had a meeting with the Developmental doctor who asked me if I was giving DS his vit D and iron – to which I honestly replied no. I was then told that I have to give iron as if DS becomes anemic, it has a long term irreversable  impact on his overall development. Scary, right? What kind of an awful mother would I be to wish to permanently impair my child by not doing what the doctor told me to do?

Anyway, I read a bit and found out that babies at risk for anemia in the first year are premature babies, babies under 3kg birth weight and formula fed babies (from what I can remember). DS does not fall into any of those catergories. I read some more and I found out that supplementing iron actually impairs the absorbtion of the iron in the breastmilk, and makes iron available to bugs in the intestines – while breast milk chelates the iron in such a way that it is only bio available to the infant and not to any bugs. Brillaint!

Back to the good doctor. She obviously had no clue what she as talking about, and yet for the last 6 months I have been fearful that perhaps DS is anemic and I caused it if he is. Well, he is not. His Hb is 11.9 and he is doing just fine without any of the precribed iron supplements. Her preventative medicine was not what my DS needed in our circumstnaces.

Good Enough Mother

So much is on my mind and I have no idea how to bring it all together. I am hearing more and more about shaken baby syndrome (SBS) or shaken baby syndrome – scurvy and it is scaring me.  I read about it in forums and even my parents are wanting to send me an article about it. I am confused.

I read about vaccine reactions being the cause of SBS and I wonder how a vaccine can cause fractures. The closest I had thought that vaccines could come to causing SBS was a baby being found not breathing and the parent shakes him/her to try and get him/her breathing again. And that the not breathing was somehow related to the recent vaccination. I know there are people far more knowledgeable than me on this issue and I am sure I am missing important information. I was just surprised to have my parents tell me they want to send me an article about SBS for me to share with others . They are totally convinced that there are people who shake their babies and that there needs to be more awareness so that people do not do this. Then I found myself thinking that maybe there are people who do shake their babies. I remember all too clearly the complete desperation when DS was a couple of weeks old and would not stop crying and I had no idea why. In such moments maybe I was vulnerable to shaking my baby? I have also read about uncontrollable crying after vaccinations and maybe parents just do not know what to do with their child and it does not even cross their minds to think of vaccinations. Maybe parents are very stressed out with the new responsibility and often the work pressures that come with trying to balance work and family…. and a crying baby is the straw that broke the camels back so to speak, when it comes to keeping your cool. I just do not understand. I do think there is an unrealistic expectation for parents to be bringing up their young children so very alone and unsupported… but my thoughts are wandering. SBS sounds awful, whatever the reasons – all possibilities are just too awful to contemplate. I hold DS a little tighter and hope that I will never need to know the pain of admitting my infant to ER and on top of that be suspected of abusing my child. It sends shudders down my spine.

In all of my pondering this issue, I was reminded of the phrase “A good enough mother” by Donald Winnicott. There is no such thing as the perfect mother, despite our aspirations, we cannot be perfect. We cannot protect out children from every danger, large and small. It is simply not possible. We can do our best, we can inform ourselves and make the best decisions that we can. I can put rubber corners on all the low furniture corners, but that does not mean DS will not pull himself up in the sofa, loose his balance and get a bump on his head. I can put all cleaning products 2 metres up, but not think to look under the desk where DS found a small coin to put in his mouth. I know that I need to be careful and create a safe environment for my DS, but I also cannot beat myself up when mistakes happen. That is life. (my heart clenches as I write this. How can I as a mum admit that I cannot control everything and ensure that my child will be safe in every possible way? Every fibre of my being wants to ensure that DS will never need to know suffering. Oy, I guess I need to read up some more on Buddhism. Suffering is part of life – no escaping it. But how do you tell yourself that when your own child suffers?)

I often find myself thinking that sociologists will one day look back on this era in the Western World and marvel that people continued to bear children despite the awful circumstances around being a parent (and child for that matter). In Hebrew you say “hafuch al hafuch” – upside down on upside down. Everything is just totally mixed up and confused.