Death toll rises

[stargirl1701]

The number of babies under 3 months who have died from whooping cough this year has risen to 13. Just so awful. My thoughts are with their families today.

Now my understanding is that for things like measles etc it is unlikely that increased virulence would evolve as a result of vaccination practices. So I was interested to see the scientists involved in the research suggesting it could be relevant for things like pertussis.

I don't follow. Why is the potential for disease severity increasing relevant to your analysis, whereas the potential for it decreasing not relevant? They both seem equally relevant to me.

Similarly, you say you don't incorporate herd immunity in to your calculation, yet the analysis can't be done without an estimate of probability of infection, which is itself a function of herd immunity.

You're analysis appears to include the negative effects of vaccination, whilst excluding the positive effects.

"Bruffin there is a difference between someone who is unvaccinated showing more severe disease than someone who develops a disease due to partial vaccine failure (total vaccine failure would be the same as unvaccinated) and more severe disease resulting from a pathogen evolving to become more virulent as a result of vaccination practices."

What are you going on about, that makes no sense whatsover!

I have said nothing about comparing vaccine and unvaccinated in the epidemic. I said that the severity of the disease appeared worse because of the greater percentage of vulnerable people catching the disease.

Jothehot
I thought it was odd when the link was to work on parasites!

I just hope medical practice has moved on from when my DD had whooping cough ten years back. She was getting iller and iller and one night she was very poorly indeed and had been "whooping" for a day or two, and vomiting and throwing herself at the walls in asphyxiation panic. I wanted her seen by a doctor to see if she needed to be admitted to hospital. I explained on the phone I was pretty sure she had whooping cough (but was not medically qualified to say) and asked if a doctor could come out as I didn't want her to infect anyone but they insisted I brought her in. They said children didn't have whooping cough any more. So we drove to the out of hours surgery where we sat in a waiting room with a TINY baby (? few days or so old - def too young to have been vaccinated). I told the receptionist I did not think my DD should be in the same room but was told to sit down and wait my turn. I stayed as far away as possible but it was probably only 4 metres or so. An hour or so later, we got to see the emergency doctor who immediately diagnosed whooping cough as DD had a paroxysm there and then in front of him on being moved. I still pray that tiny baby was not infected. I think GP practices are not used to dealing with infectious diseases so much any more....

:pointless:

OK final time, then I give up

a) Elaine comes out with her usual idea that people don't vaccinate because they know they're hitchiking a free ride using herd immunity

b) I point out that this isn't a factor in decision making in the cases I know. For example I think that in not vaccinating against measles that leaves ds2 and ds3 at higher risk of catching measles than ds1 who is vaccinated. In other words I don't rely on the concept of herd immunity to go around feeling all super safe and untouchable. I rather assume my children will be exposed at some stage (and in the case of measles get it - as that's what tends to happen with measles exposure).

c) I then say however, if diseases increase in virulence as a result of vaccination practices then I would consider that to be important. So for example I think it reasonably likely my children might get measles. I believe it highly likely that they would not suffer long term effects (and yes yes I know all about measles damage - my mum is permanently damaged from measles blah blah blah). However, if future research showed that measles disease was increasing in virulence as a result of vaccination practices (actually unlikely in the case of measles for reasons described in the papers above - I'm just using measles as an example as it is so contagious) then obviously I would factor that into decision making.

Hope - the same happened to me when ds1 (who has been vaccinated) had suspected measles. We were told to wait in a crowded waiting room, I suggested that wasn't sensible and got moved to a room with a baby. Presumably it wasn't measles in our case, but it seemed a stupid thing to do before diagnosis.

but you wouldn't factor it in if measles became less virulent? Why not?

Well then the risk from measles disease would be less. Obviously. Why would that make me think about vaccinating my children? Which is what we were taking about. Given that we're running the risk of the diseases in the first place because of family history, if a disease decreases in virulence that's hardly a reason to vaccinate children who are believed to me more susceptible to vaccination damage than the average child.

Saintly: exactly the same - kids with possibly serious infectious diseases should not be in the waiting room, or a room with a baby (!). I am glad your DS1 didn't have measles btw.

I'm sure you don't need me to explain why any future analysis needs to take account of all changes, not just changes which shift the decision in favour of vaccination. Perhaps virulence reduces a little, but at the same time herd immunity drops a lot, thereby justifying a switch to vaccination.

Trying another approach; how would you feel if I habitually posted on vaccine threads to observe that a wonderful side-effect of vaccination is it's capacity to reduce disease virulence in unvaccinated individuals, and I cited Read's nature paper to support this. I'm pretty sure, you'd be hot on my heels to say I was presenting a partial view.

No I wouldn't.

Remember when I had a child I believed to be at average risk of damage from a vaccination I vaccinated. If I only had children who I believed to be at average risk I would presumably vaccinate.

I never said anything about you hitchhiking a free ride Saintly. I think you're projecting again (a little bit rudely and snidely but I'm used to that).

Point is that you can't do a risk analysis without actually being able to estimate risk.

Unless you've assumed a probability of 1, ie that your children WILL get whatever disease you're vaccinating against!

Which means you've assumed your children will get measles, polio, mumps, diptheria, Hib, pertussis, flu etc.

And you still think it's riskier than getting the vaccine?! On what evidence????

You said once that your doctor said that your kids will probably be fine being vaccinated and probably be fine not being vaccinated. S/he's completely right, unvaccinated kids don't keel over like flies, of course not. But I'd guess that a lot of the 'probably be fine not being vaccinated' is based on the premise that your children won't be exposed to the diseases in question. Presumably s/he would advise differently in the face of a diptheria epidemic.

I'm pretty sure you said as well at some point that your strategy is to reduce exposure to any potential pathogen as you think any illness could be a trigger. Given that you also said you'd researched this a lot and had the support of your doctors, I thought that made sense to me.

But then if that's the case, not taking into account the protective effect of herd immunity in reducing exposure to pathogens is completely irrational. I really don't understand your thought process regardly the probability of exposure.

You'reremarkably interested in my family history. It's a bit intrusive tbh. The doctor's comments regarding vaccination were made before we (or they) had full understanding of the extent of ds1's brain damage. Other doctors have said other things since. Iirc I was using that example in a rather different way than in relation to the decisions we finally made.,

The question has nothing to do with the details of your family. The question is: when you evaluate the pros and cons of a vaccination, do you consider the probability of catching the disease? If you do, as you surely must, you implicitly incorporate the level of herd immunity in your decision.

I think the confusion perhaps arose because you thought Elaine was talking about explicitly including herd immunity in your analysis.

I do not factor herd immunity into my decision. I suspect I somewhat over estimate the risk of catching (say) measles. For something like men C I assume the risk of catching that is low, but not due to herd immunity, because the risk of developing men C is low anyway and was in pre-vac days. It's particularly low at the moment because of their age. By the time the kids are in the next risk age group for men C they will be able to decide for themselves whether they want it anyway.

I have never met anyone who would say (as Elaine suggested) 'oooh herd immunity isn't working anymore, I've changed my mind vaccinate please'. Because generally, the people I know do realise that by not vaccinating their child may well get the disease.

This was what I was replying to - to clear up the apparent confusion.

Unfortunately, people who don't vaccinate can no longer rely on herd immunity to protect their own babies. Probably explains the increasing rates of vaccination. I suspect the same pattern will occur any vaccine preventable disease which recurs since it's easy to forget, as a society, how nasty they are

I believe this shows a lack of understanding as to why people refuse or delay vaccinations.

I stated earlier other reasons why vaccination rates may well have increased (no available tetanus without aP, people for whom wP was contraindicated being able to receive aP).

If, as you say, you have estimated the risk of catching measels, by definition, you have incorporated herd immunity. The dynamics of a disease can not under any circumstances be calculated without the density of susceptibles, and the density of susceptibles is the overall population density multiplied by the level of herd immunity (definition).

I don't think you understand herd immunity.

I don't think you understand what I am saying. Read Elaine's comment, read my reply. If you don't understand never mind.

I assume if my kids come into contact with measles they will get it. I assume the likelihood of them coming into contact with measles is high enough for it to be reasonably likely, they're still unvaccinated. Because herd immunity (presence or not thereof has not played a role in my decision making)

That's it, nothing more complicated. As for why we headed down this track read (again) Elaine's comments about parents rushing out to vaccinate once they realise herd immunity is doomed doomed doomed.

Have a nice evening ladies - I give up, can't be clearer than that). although feel free to actually read my posts which clearly state my position.

Just trying to make sense of what you're saying saintly.

I don't why you find it intrusive when you've made these comments on a public forum on threads on which I was actively engaged. I guess I have a good memory.

And it is true that unfortunately people can no longer rely on herd immunity to protect their own babies against pertussis. This applies to those whose babies are too young to be vaccinated as well as those who choose not to vaccinate later.

And I absolutely think that as soon as vaccine preventable disease start coming back and children start to die, vaccination rates will go up (as indeed we see with pertussis). You disagree (because you don't think people take into account the probability of actually being exposed to a disease as you didn't do so!). Fine.

I disagree because I actually talk to people who haven't vaccinated about their reasons why. Rather than make assumptions.

Given that vaccination rates are the been highest they've ever I'm surprised you think all these vaccine preventable diseases are going to appear again.

*ever been

BTW, it's not just the probabiltiy of exposure which is affected by herd immunity. It's also the average age of infection which goes up when there is a herd immunity effect. Since measles is usually worse in older children and adults and since herd immunity for measles isn't so great, chances are that unvaccinated kids are going to get measles but will get it at an older age when it'll be more severe.

But if you don't take herd immunity into account, then of course this won't be an issue but if you pretend it doesn't exist then it won't affect you

No, most vaccine preventable diseases shouldn't reappear if vaccine rates remain high. I agree with you. So hopefully such a scenario won't happen.

And in the meantime you, and your friends who don't vaccinate, will benefit (for the most part) from herd immunity even though you don't believe in it.

Not taking something into account in my decision making doesn't mean I pretend it doesn't exist. It's just not part of the decision making As you well know, I mean that I do not rely on herd immunity to assume my kids are protected, I assume they are at risk from the disease, presumably rather over estimating their risk of actually getting measles. I would have thought you would approve of that approach.

I am well aware that measles becomes more dangerous at puberty which is why - if you search my posts you will find i have previously said ds2 might have a measles (single) vaccine at some stage. This decision is based on severity of disease vs risk of severe brain damage (basically the two issues I am interested in). Yes indeed the severity does increase for measles and so the decision - for ds2 in particular - may change. I have always been clear about that on here. Stated again although largely irrelevant to this thread.